The Concept Library

The cytoplasmic breakdown of one glucose to two pyruvate, with a net gain of 2 ATP.

Biochemistry · Carbohydrate Metabolism

The mitochondrial oxidation of acetyl-CoA that supplies electron carriers for ATP production.

Biochemistry · Energy Metabolism

The hepatic pathway that converts toxic ammonia into water-soluble urea for excretion.

Biochemistry · Amino Acid Metabolism

The rapid vascular and cellular response of tissue to injury or infection.

Pathology · Inflammation & Repair

Two forms of cell death: programmed and controlled vs traumatic and passive.

Pathology · Cell Injury & Death

What the body does to a drug over time.

Pharmacology · Pharmacokinetics

G-protein receptors for adrenaline/noradrenaline that drive the sympathetic response.

Pharmacology · Autonomic Pharmacology

The final stage of aerobic respiration that produces most of the cell's ATP.

Biochemistry · Cellular Respiration

Essential micronutrients grouped by how they are absorbed and stored.

Biochemistry · Vitamins

The semi-conservative process by which a cell copies its DNA before division.

Biochemistry · Molecular Biology

Excess fluid in the interstitial space, driven by disturbed Starling forces.

Pathology · Fluid & Electrolyte Balance

A simple grading of a patient's fitness before anaesthesia and surgery.

Anaesthesiology · Preoperative Assessment

The three goals that define balanced general anaesthesia.

Anaesthesiology · Anaesthesia Basics

The basic shades that let you read any plain radiograph.

Radiology · Radiology Basics

Matching the right scan to the clinical question.

Radiology · Imaging Modalities

The two main cross-sectional imaging techniques and when to use each.

Radiology · Imaging Modalities

The three primary embryonic tissue layers from which every organ develops.

Anatomy · Embryology

The classic patterns by which single genes pass through families.

Biochemistry · Genetics

The commonest chromosomal disorder, caused by an extra chromosome 21.

Pediatrics · Genetic Disorders

How the body repairs tissue after injury.

General Surgery · Wound Healing

The commonest radiograph — a systematic read avoids missed findings.

Radiology · Radiology Basics

Imaging with high-frequency sound waves — no ionising radiation.

Radiology · Imaging Modalities

Loss of sensation for surgery — delivered at different levels.

Anaesthesiology · Anaesthesia

The four levels of organisation that give a protein its shape and function.

Biochemistry · Protein Structure

The changes cells undergo when stressed or damaged.

Pathology · Cell Injury & Adaptation

How the body's total water is distributed between compartments.

Physiology · Body Fluids

Biological catalysts that speed up reactions without being consumed.

Biochemistry · Enzymes

Reversible changes in cell size, number or type in response to stress.

Pathology · Cellular Adaptations

Synthesis of glucose from non-carbohydrate precursors (lactate, glycerol, amino acids).

Biochemistry · Carbohydrate Metabolism

Storage and breakdown of glycogen, and the diseases of its enzymes.

Biochemistry · Carbohydrate Metabolism

A glucose pathway generating NADPH and ribose-5-phosphate.

Biochemistry · Carbohydrate Metabolism

Agents that improve tissue distinction on imaging.

Radiology · Imaging Principles

Principles that minimise ionising-radiation exposure.

Radiology · Radiation Protection

A life-threatening hypermetabolic reaction to anaesthetic triggers.

Anaesthesiology · Anaesthetic Complications

Imaging using radioactive tracers to show function, not just anatomy.

Radiology · Nuclear Medicine

The morphological types of unregulated cell death.

Pathology · Cell Injury & Death

What a drug does to the body - its effects and mechanisms.

Pharmacology · Pharmacodynamics

Energy from fat during fasting, and the ketones it produces.

Biochemistry · Metabolism

Supporting a newborn that does not breathe well at birth.

Pediatrics · Resuscitation

A structured approach to any acutely unwell patient - assess and treat in order.

General Medicine · Emergency Assessment

Early recognition of clinical deterioration using track-and-trigger scores.

General Medicine · Clinical Deterioration

Problems arising after surgery, often timed predictably.

General Surgery · Postoperative Care

Rapidly recognising serious illness in a child.

Pediatrics · Pediatric Assessment

Controlling pain after surgery using a stepwise, multimodal approach.

Anaesthesiology · Pain Management

Matching the imaging test to the clinical question and to safety.

Radiology · Diagnostic Imaging

A multifactorial assessment of the older person who falls.

General Medicine · Geriatric Assessment

The specific antidotes for common poisonings.

Pharmacology · Antidotes

Recognising and classifying unwanted effects of drugs.

Pharmacology · Adverse Drug Reactions

The initial resuscitation sequence for a collapsed child.

Pediatrics · Basic Life Support

The ways a change in DNA sequence alters the reading of a gene, from a single silent base swap to a whole shifted reading frame.

Biochemistry · Genetics

A family of laboratory methods that separate molecules, transfer them to a membrane, then detect a specific target with a nucleic-acid probe or an antibody, depending on the method.

Biochemistry · Molecular Biology Techniques

HGPRT recycles purine bases back into nucleotides; its complete absence produces the Lesch-Nyhan phenotype.

Biochemistry · Nucleotide Metabolism

The hypothalamic balance between heat gain and heat loss that holds core temperature steady, including during fever and exercise.

Physiology · Homeostasis

The process by which RNA polymerase copies a gene's DNA template strand into a complementary strand of RNA.

Biochemistry · Molecular Biology

The laboratory tools that cut, join, copy and read DNA, which underpin modern molecular biology and biotechnology.

Biochemistry · Molecular Biology

The intracellular signals that relay a hormone's message from a surface receptor to the machinery inside the cell.

Biochemistry · Cell Signaling

Inherited enzyme defects in amino-acid metabolism, each blocking one step and causing a characteristic build-up.

Biochemistry · Amino Acid Metabolism

In eukaryotes, the processing steps that turn a freshly made primary RNA (pre-mRNA) transcript into a mature messenger RNA before it leaves the nucleus.

Biochemistry · Gene Expression

How the liver chemically alters foreign compounds and drugs, usually making them more water-soluble and easier to excrete, in two broad phases.

Biochemistry · Detoxification

A cluster of bacterial genes, switched on and off together, that lets a bacterium make the enzymes to use lactose only when lactose is present.

Biochemistry · Gene Regulation

The set of rules by which the sequence of bases in messenger RNA is read in triplets to specify the amino acids of a protein.

Biochemistry · Genetic Code

The systems that find and correct damage or mistakes in DNA, protecting the genetic code from mutations that could cause cancer or cell death.

Biochemistry · DNA Repair

The abnormal deposit of calcium salts in body tissues, occurring either in already-damaged tissue or because of a disturbance of calcium or phosphate metabolism.

Pathology · Pathological Calcification

The ways substances cross the cell membrane, either downhill without energy or uphill using energy, which lets a cell control what enters and leaves.

Physiology · Cell Membrane

The changes in the heart, lungs, muscles and metabolism that let the body meet the greatly increased demand for oxygen and energy during exercise.

Physiology · Exercise Physiology

How the body repairs damaged tissue, either by regenerating the original cells or by filling the gap with a fibrous scar.

Pathology · Tissue Repair

Laboratory methods that colour specific tissue components or use antibodies to reveal particular molecules, helping a pathologist identify and classify disease.

Pathology · Laboratory Techniques

Metals and other elements the body needs only in tiny amounts, which act as helpers for enzymes; too little or too much causes specific diseases.

Biochemistry · Micronutrients

A laboratory method that makes millions of copies of a chosen stretch of DNA, so that a tiny sample can be studied or detected.

Biochemistry · Molecular Biology Techniques

A laboratory technique that separates molecules such as DNA or proteins by pulling them through a gel with an electric field, sorting them by size and charge.

Biochemistry · Molecular Biology Techniques

The reactions that shuffle the nitrogen of amino acids, the first step in using them for energy and in getting rid of surplus nitrogen safely.

Biochemistry · Amino Acid Metabolism

The simplest amino acid, glycine, which is a building block for an unusually wide range of important molecules in the body.

Biochemistry · Amino Acid Metabolism

How the body makes and breaks down the pyrimidine bases of DNA and RNA, a pathway that differs in key ways from purine metabolism.

Biochemistry · Nucleotide Metabolism

How the body makes creatine to store quick energy in muscle, and how its breakdown product creatinine is used to judge kidney function.

Biochemistry · Amino Acid Metabolism

The four vitamins that dissolve in fat, are stored in the body, and each have distinct jobs, so both deficiency and excess can cause disease.

Biochemistry · Vitamins

A dangerous state in which blood flow is too low to meet the body's needs, so tissues are starved of oxygen; it has several types by cause.

Pathology · Shock

Changes in the number or structure of chromosomes that cause inherited syndromes and drive some cancers.

Pathology · Chromosomal Disorders

How unstable oxygen molecules called free radicals damage cells, a mechanism behind ageing, inflammation and many diseases.

Pathology · Cell Injury

Coloured substances that build up inside cells, some made by the body and some from outside, whose pattern helps recognise disease.

Pathology · Cellular Pigments

The death (necrosis) of body tissue from a loss of blood supply, sometimes worsened by infection, seen in three main forms.

Pathology · Gangrene

The B-complex vitamins and vitamin C, which dissolve in water, are not stored for long, and mostly act as helpers for enzymes.

Biochemistry · Vitamins

How the body builds fatty acids from small carbon units when energy is plentiful, storing surplus fuel as fat.

Biochemistry · Lipid Metabolism

Inherited diseases in which a missing enzyme lets undigested material pile up inside the cell's lysosomes, damaging organs over time.

Biochemistry · Lysosomal Storage Diseases

Long sugar chains that cushion joints and hold tissues together, and the inherited diseases that arise when the body cannot break them down.

Biochemistry · Glycosaminoglycans

How the body switches its whole metabolism between storing fuel after a meal and releasing fuel between meals, coordinated by hormones.

Biochemistry · Metabolic States

Local hormone-like messengers made from a fatty acid in cell membranes, which control inflammation, pain, fever, clotting and blood flow.

Biochemistry · Cell Signaling Molecules

The steady electrical voltage across the membrane of a resting cell, set up mainly by potassium, which nerve and muscle cells use as their starting point.

Physiology · Cell Membrane Physiology

The different ways a drug can be given to the body, each affecting how fast and how completely it reaches the bloodstream.

Pharmacology · Pharmacokinetics

What a drug does to the body: how it binds to targets such as receptors to produce its effect, and what decides how strong that effect is.

Pharmacology · Pharmacodynamics

How one drug can speed up or slow down the liver enzymes that break down another drug, changing its level in the body and causing interactions.

Pharmacology · Drug Metabolism

How one drug can change the effect of another when they are taken together, sometimes helpfully but often causing harm.

Pharmacology · Pharmacokinetics & Pharmacodynamics

The many things about a person and their situation that change how a drug affects them, so the same amount can act differently in different people.

Pharmacology · Pharmacokinetics & Pharmacodynamics

How drugs act at the adrenaline (adrenergic) receptors, which control the heart, blood vessels and airways, by switching them on or blocking them.

Pharmacology · Autonomic Pharmacology

How repeated use of a drug can lead the body to need more for the same effect, to depend on it, and sometimes to compulsive use.

Pharmacology · Pharmacokinetics & Pharmacodynamics

A diet that supplies all the nutrients the body needs in the right amounts and proportions, from energy-giving foods to vitamins and minerals.

Community Medicine · Nutrition

The study of how work can harm health and how to prevent it, including the lung and other diseases caused by particular jobs.

Community Medicine · Occupational Health

Why clean water and the safe disposal of human waste are among the most important public-health measures for preventing disease.

Community Medicine · Public Health Measures

The planned use of information and teaching to help people make healthy choices and change harmful behaviours.

Community Medicine · Health Education

The system of keeping vaccines cold from the factory to the person, so they stay effective; a break in it can spoil them.

Community Medicine · Immunization Programs

A group of blood tests that together show how well the liver, kidneys, heart and other organs are working.

Biochemistry · Organ Function Tests

The idea that a laboratory result is judged against a normal range, and that some extreme values need fast attention.

Biochemistry · Laboratory Medicine

Bacterial enzymes that cut DNA at specific sequences, used as molecular scissors to move genes between organisms.

Biochemistry · Molecular Biology

Diseases that result from a lack of specific vitamins or minerals in the diet, common where diets are poor or unbalanced.

Community Medicine · Nutrition and Deficiency Disorders

Inherited enzyme defects that block a step in the body's chemistry, so harmful substances build up or vital products run short.

Pediatrics · Inborn Errors of Metabolism

The feeding of babies with breast milk, the ideal first food, and the way solid foods are added as the baby grows.

Pediatrics · Infant Nutrition

The checks made before an operation to judge a patient's fitness and to reduce the risks of surgery and anaesthesia.

General Surgery · Preoperative Care

The continuous watching of a patient's vital functions during anaesthesia to keep them safe while they cannot respond.

Anaesthesiology · Anaesthesia Monitoring

Medicines given before an anaesthetic to calm the patient and to make the anaesthetic safer and smoother.

Anaesthesiology · Premedication

The normal ranges of the body's key measurements, which act as a baseline against which illness is judged.

Physiology · Normal Values

The sequence of mechanical and electrical events in one heartbeat (systole + diastole).

Physiology · Cardiac Physiology

A spectrum of acute coronary syndromes caused by a sudden reduction in coronary blood flow, including unstable angina, NSTEMI and STEMI.

General Medicine · Ischemic Heart Disease

The heart is unable to pump enough blood to meet the body's needs.

General Medicine · Heart Failure

Circulatory failure causing inadequate tissue perfusion and oxygen delivery.

General Surgery · Shock

A chronic disease in which lipid plaques build up within artery walls.

Pathology · Atherosclerosis

The arteries that supply oxygenated blood to the heart muscle itself.

Anatomy · Cardiac Anatomy

The volume of blood the heart pumps each minute.

Physiology · Cardiac Physiology

Persistently raised arterial blood pressure — the 'silent killer'.

General Medicine · Hypertension

How the fetus routes blood around its non-functioning lungs and liver.

Physiology · Fetal Circulation

The drug classes used to lower high blood pressure.

Pharmacology · Antihypertensive Drugs

Death of heart muscle from a blocked coronary artery.

General Medicine · Ischemic Heart Disease

Particles that carry fats (lipids) through the blood.

Biochemistry · Lipid Metabolism

Structural heart defects that are present from birth.

Pediatrics · Congenital Heart Disease

A detached intravascular mass (solid, liquid or gas) carried to a distant site.

Pathology · Vascular Pathology

Tissue necrosis caused by loss of blood supply (ischaemia).

Pathology · Vascular Pathology

The surface recording of the heart's electrical activity.

Physiology · Electrocardiography

The balance of hydrostatic and oncotic pressures governing fluid movement across capillaries.

Physiology · Microcirculation

Identifying common heart-rhythm disturbances on the ECG.

General Medicine · Arrhythmias

A structured differential of acute chest pain, prioritising the life-threats.

General Medicine · Chest Pain

Assessing the blue newborn and separating cardiac from respiratory causes.

Pediatrics · Neonatal Cyanosis

Evaluating the sensation of a fast, forceful or irregular heartbeat.

General Medicine · Palpitations

The blood supply to the heart muscle itself, and the special feature that most of it flows during diastole.

Physiology · Coronary Circulation

The heart chamber that receives deoxygenated blood from the body through the venae cavae and the coronary sinus and passes it to the right ventricle.

Anatomy · Heart Anatomy

An immune complication that can follow a throat infection with group A streptococcus, in which cross-reacting immune responses damage the heart, joints and other tissues.

Pathology · Rheumatic Heart Disease

The special features of heart muscle that let it beat on its own, in a coordinated way, without tiring, throughout life.

Physiology · Cardiac Muscle

The curved top of the aorta in the chest that gives off the great arteries to the head and arms and arches over the root of the left lung.

Anatomy · Aorta

How blood that has supplied the heart muscle is collected and returned, mostly through the coronary sinus into the right atrium.

Anatomy · Heart Anatomy

An abnormal, permanent bulging of a blood vessel wall (or the heart), which can leak, burst or throw off clots.

Pathology · Vascular Pathology

Diseases of the heart muscle itself that weaken the heart's pumping, grouped into three main patterns by how the muscle changes.

Pathology · Cardiac Pathology

Drugs that correct abnormal heart rhythms, classically grouped by the ion channel or receptor they act on.

Pharmacology · Antiarrhythmic Drugs

The links between neighbouring arteries that provide an alternative route for blood if one vessel is blocked.

Anatomy · Vascular Anatomy

Drugs that relieve the chest pain of angina by widening blood vessels and easing the heart's workload.

Pharmacology · Pharmacology of Ischemic Heart Disease

Drugs that relieve symptoms and prolong life in a failing heart by reducing its workload and controlling fluid overload.

Pharmacology · Pharmacology of Heart Failure

Drugs that make platelets less sticky to prevent the clots that cause heart attacks and strokes.

Pharmacology · Pharmacology of Thrombosis

Swollen, twisted surface veins of the legs caused by failure of the valves that keep blood flowing upward.

General Surgery · Venous Disorders

Narrowing of the arteries to the legs that starves the muscles of blood, causing cramping pain on walking.

General Surgery · Peripheral Vascular Disease

Drugs that lower blood cholesterol to reduce the fatty build-up in arteries and the risk of heart attacks and strokes.

Pharmacology · Lipid-Lowering Drugs

Drugs that block beta-adrenergic receptors, slowing the heart and reducing its force, used in many heart conditions.

Pharmacology · Beta Blockers

Drugs that block the entry of calcium into muscle cells, relaxing blood vessels and, for some, slowing the heart.

Pharmacology · Calcium Channel Blockers

Infection of the inner lining of the heart, usually a valve, where clumps of bacteria and clot form growths called vegetations.

General Medicine · Endocarditis

The features and habits that raise a person's chance of heart attack and stroke, some changeable and some not.

General Medicine · Cardiovascular Risk Factors

The chest X-ray changes that point to narrowing of the mitral valve, from the back-pressure it causes in the lungs.

Radiology · Valvular Heart Disease

Disorders of the heart valves, which either narrow (stenosis) and block flow or leak (regurgitation) and let blood flow backward.

General Medicine · Valvular Heart Disease

The sigmoid curve relating haemoglobin's oxygen saturation to the partial pressure of oxygen.

Physiology · Gas Transport

Two common obstructive airway diseases that both cause wheeze and breathlessness.

General Medicine · Obstructive Lung Diseases

The dome-shaped main muscle of respiration separating the thorax from the abdomen.

Anatomy · Respiratory Muscles

Keeping the airway open and protected — the first priority in a collapsing patient.

Anaesthesiology · Airway Management

Infection and inflammation of the lung's air sacs (alveoli).

General Medicine · Pneumonia

Measurement of the air volumes moved by the lungs.

Physiology · Pulmonary Function Tests

Supplemental oxygen delivery and its devices.

Anaesthesiology · Oxygen Therapy

A systematic read of an arterial blood gas to find acid-base and oxygenation problems.

Physiology · Acid-Base Balance

A structured differential of acute dyspnoea.

General Medicine · Dyspnoea

Assessing and managing wheeze in a child by likely cause and age.

Pediatrics · Pediatric Respiratory Disorders

Spotting air in the pleural space on a chest radiograph.

Radiology · Chest Radiology

How the brainstem and the chemoreceptors set the depth and rate of breathing, minute by minute, without you thinking about it.

Physiology · Control of Breathing

Oxygen can fail tissues at four different points, and naming which point is failing explains the whole clinical picture.

Physiology · Hypoxia

The gap between two adjacent ribs, filled by three layers of intercostal muscle and carrying the intercostal nerve and vessels in a groove under the upper rib.

Anatomy · Thoracic Wall

The larger of the two lungs, made of three lobes divided by two fissures, with a hilum on its inner surface where the airways and vessels enter.

Anatomy · Lung Anatomy

A lung disease in which the air sacs are permanently enlarged and their walls destroyed, reducing the surface for gas exchange and trapping air.

Pathology · Chronic Lung Disease

The central compartment of the chest between the two lungs, holding the heart, great vessels, oesophagus, trachea and other structures.

Anatomy · Thoracic Cavity

The smaller of the two lungs, with two lobes and a notch that makes room for the heart, and a hilum where the airways and vessels enter.

Anatomy · Lung Anatomy

How harmful substances in the air we breathe, indoors and outdoors, damage health, especially the lungs and heart.

Community Medicine · Environmental Health

Inhaled and oral drugs that open the airways and calm airway inflammation in asthma and chronic obstructive pulmonary disease.

Pharmacology · Drugs for Asthma and COPD

The windpipe and the branching air tubes that carry air from the throat down into the lungs.

Anatomy · Lower Respiratory Tract

A collection of fluid in the space around the lung, which compresses the lung and causes breathlessness.

General Medicine · Pleural Diseases

Two common viral chest infections of young children, one narrowing the voice box and the other the smallest airways.

Pediatrics · Pediatric Respiratory Infections

A sudden flooding of the lungs with fluid, usually because the heart cannot cope, causing severe breathlessness.

General Medicine · Pulmonary Oedema

An oblique passage in the lower abdominal wall transmitting the spermatic cord (male) or round ligament (female).

Anatomy · Abdominal Wall & Hernias

Inflammation of the vermiform appendix — the commonest surgical abdominal emergency.

General Surgery · Appendicitis

Yellow discolouration of a newborn from raised serum bilirubin.

Pediatrics · Jaundice

A blockage that prevents the normal passage of bowel contents.

General Surgery · Intestinal Obstruction

Stones in the gallbladder and the inflammation they can cause.

General Surgery · Gallbladder Disorders

Severe undernutrition from inadequate protein and/or calories.

Pediatrics · Malnutrition

A leading cause of childhood death, largely preventable with rehydration.

Pediatrics · Pediatric Gastroenterology

Inflammation of the liver caused by hepatitis viruses A to E.

Microbiology · Viral Hepatitis

The serous membrane lining the abdominal cavity and covering its organs.

Anatomy · Peritoneum

Ulceration of the stomach or duodenum from acid and mucosal injury.

General Medicine · Peptic Ulcer Disease

Irreversible scarring of the liver with progressive loss of function.

General Medicine · Chronic Liver Disease

Protrusion of an organ through a weak point in its containing wall.

General Surgery · Hernias

Sudden, severe abdominal pain that may need urgent surgery.

General Surgery · Acute Abdomen

Secretion of hydrochloric acid by parietal cells, regulated in three phases.

Physiology · Gastric Physiology

A systematic approach to the plain abdominal film.

Radiology · Abdominal Imaging

A structured differential of yellow discolouration from raised bilirubin.

General Medicine · Jaundice

A structured differential of blood passed per rectum.

General Surgery · Lower GI Bleeding

Reading a liver blood panel to localise the problem.

Pathology · Liver Function Tests

Reading the abdominal film in suspected obstruction.

Radiology · Abdominal Radiology

A structured approach to difficulty swallowing.

General Surgery · Dysphagia

Two secretions from one gland: a bicarbonate-rich fluid that neutralises stomach acid, and an enzyme-rich fluid that digests all three food groups.

Physiology · Pancreas

The terminal part of the gut, whose upper and lower halves differ in origin, lining, blood supply, nerve supply and drainage, divided by the pectinate line.

Anatomy · Large Intestine

The largest salivary gland, wrapped around the ramus of the mandible and famous for the structures that pass through it.

Anatomy · Salivary Glands

How the breakdown of haem produces bilirubin, and how a block at different points gives pre-hepatic, hepatic or post-hepatic jaundice.

Biochemistry · Bilirubin Metabolism

The coordinated movement of a food bolus from mouth to stomach, in three phases, that protects the airway on the way.

Physiology · Gastrointestinal Motility

The end stage of many chronic liver diseases, in which diffuse scarring and regenerative nodules replace the normal liver architecture.

Pathology · Liver Pathology

How the products of digestion are taken up across the lining of the small intestine into the blood and lymph, aided by a huge surface area.

Physiology · Small Intestine

The coordinated muscle movements of the gut that mix food with the digestive juices and push it along, from the stomach to the anus.

Physiology · Gastrointestinal Motility

Two long-term inflammatory diseases of the bowel, Crohn disease and ulcerative colitis, that differ in where and how deeply they affect the gut.

Pathology · Inflammatory Bowel Disease

The system of veins that carries nutrient-rich blood from the gut to the liver before it returns to the heart, with escape routes if it becomes blocked.

Anatomy · Portal Circulation

The first and shortest part of the small intestine, a C-shaped tube curving around the head of the pancreas that receives bile and pancreatic juice.

Anatomy · Small Intestine

The largest internal organ, sitting under the right ribs, which processes nutrients and toxins and has a double blood supply.

Anatomy · Liver Anatomy

The muscular bag of the upper abdomen that stores and churns food, with a rich blood supply and a lymphatic drainage that matters in stomach cancer.

Anatomy · Stomach Anatomy

A soft gland lying across the back of the upper abdomen that makes digestive juice and the hormones insulin and glucagon.

Anatomy · Pancreas Anatomy

The greenish fluid made by the liver that helps digest and absorb fats and gets rid of waste such as old pigment and cholesterol.

Physiology · Bile and Gallbladder

The hormones released by the gut wall that coordinate digestion, switching the stomach, pancreas and gallbladder on and off at the right times.

Physiology · Gastrointestinal Hormones

The build-up of fat inside liver cells, the commonest liver abnormality, which can be harmless or progress to inflammation and scarring.

Pathology · Liver Pathology

Solid stones that form in the gallbladder from bile, which can block the flow of bile and cause pain, inflammation and jaundice.

Pathology · Gallbladder Pathology

The first large artery of the abdominal aorta, which supplies the foregut organs through its three main branches.

Anatomy · Abdominal Arteries

The three parts of the primitive gut tube and the adult organs, arteries and nerve supply that develop from each.

Anatomy · Gut Development

Drugs that heal and prevent stomach and duodenal ulcers by reducing acid or protecting the lining.

Pharmacology · Drugs for Peptic Ulcer

Drugs that prevent or relieve nausea and vomiting, chosen according to the cause of the sickness.

Pharmacology · Antiemetics

A common small pouch left over from early development on the small intestine, which can cause problems that mimic appendicitis.

Anatomy · Small Intestine

A collection of pus within the liver, most often from amoebic infection or from bacteria reaching the liver.

General Surgery · Liver Infections

Growths of the salivary glands, most of which occur in the parotid gland and most of which are benign.

General Surgery · Salivary Glands

A twisting of the loose sigmoid colon on its stalk, which blocks the bowel and can cut off its blood supply.

General Surgery · Large Intestine

A cystic disease caused by the larva of a dog tapeworm, most often forming slow-growing cysts in the liver.

General Surgery · Liver and Biliary Tract

Tuberculosis affecting the bowel, its lymph nodes and the lining of the abdomen, a common surgical form of the disease in some regions.

General Surgery · Tuberculosis of GI Tract

Cancer of the stomach lining, often found late because its early symptoms are vague, with a generally poor outlook.

General Surgery · Stomach Tumours

Cancer of the pancreas, often found late, classically causing painless yellowing of the skin when it blocks the bile duct.

General Surgery · Pancreatic Tumors

Cancer of the food pipe, which narrows it and causes progressive difficulty swallowing, first for solids then for liquids.

General Surgery · Esophageal Tumors

A lump formed when the body walls off an inflamed appendix, a complication that changes how appendicitis is handled.

General Surgery · Appendicitis

Cancer of the mouth, strongly linked to tobacco and areca nut, often preceded by visible premalignant patches.

General Surgery · Oral Cavity Tumors

Conditions in which the gut fails to absorb nutrients properly, leading to weight loss, bulky stools and deficiencies.

General Medicine · Malabsorption

The spectrum of liver damage caused by long-term heavy drinking, from a fatty liver to hepatitis and finally cirrhosis.

General Medicine · Liver Disorders

Sudden inflammation of the pancreas as its own digestive enzymes are activated and begin to digest the gland.

General Medicine · Pancreatic Disorders

Blockage of the outlet of the stomach, so food cannot pass into the intestine, causing vomiting of stale food.

General Surgery · Stomach Disorders

A thickening of the muscle at the stomach's outlet in young babies, causing forceful vomiting and blocking milk from passing.

General Surgery · Stomach Disorders

Long-standing inflammation that permanently scars the pancreas, so it can no longer digest food or make enough insulin.

General Medicine · Pancreatic Disorders

Cancer of the colon or rectum, a common cancer that often grows from a polyp over years and can be caught early by screening.

General Surgery · Colorectal Cancer

The functional unit of the kidney; GFR is the rate at which plasma is filtered.

Physiology · Renal Physiology

The hormonal cascade that regulates blood pressure and fluid balance.

Physiology · Renal Physiology

How the body keeps arterial blood pH within a tight range (~7.35–7.45).

Physiology · Acid–Base Balance

A progressive, irreversible decline in kidney function.

General Medicine · Chronic Kidney Disease

Drugs that increase urine output, used in oedema and hypertension.

Pharmacology · Diuretics

How the kidney concentrates urine.

Physiology · Renal Physiology

A rapid fall in kidney function over hours to days.

General Medicine · Acute Kidney Injury

Adjusting drugs when the kidney or liver cannot clear them normally.

Pharmacology · Drug Dosing in Renal Disease

Choosing the right fluid, volume and rate for a patient.

Anaesthesiology · Fluid Management

A high serum potassium that can cause fatal arrhythmia.

General Medicine · Electrolyte Disorders

A low serum sodium assessed through the patient's fluid status.

General Medicine · Electrolyte Disorders

Investigating blood in the urine.

General Surgery · Haematuria

A muscular hollow organ in the pelvis that stores urine, lined by transitional epithelium and emptied by the detrusor muscle under nervous control.

Anatomy · Urinary Bladder

Chemical systems that resist changes in pH by mopping up or releasing hydrogen ions, keeping blood pH within a narrow healthy range.

Biochemistry · Acid-Base Balance

Diseases that damage the filtering units of the kidney, presenting in two broad patterns: a nephritic picture of inflammation and a nephrotic picture of heavy protein loss.

Pathology · Glomerular Diseases

The four ways blood pH can be disturbed, grouped by whether the problem starts in the metabolism or the breathing, and how the body compensates.

Biochemistry · Acid-Base Balance

A pair of bean-shaped organs at the back of the abdomen that filter blood to make urine, wrapped in protective layers of fat and fascia.

Anatomy · Kidney Anatomy

Blood and urine tests that measure how well the kidneys filter waste, chiefly urea, creatinine and the clearance of a marker substance.

Biochemistry · Renal Function Tests

The two main charged salts of body fluids, whose blood levels are tightly controlled and whose disturbance affects nerves, muscle and the heart.

Biochemistry · Electrolyte Balance

How the body makes and clears uric acid, the end product of purine breakdown, and how its excess causes gout.

Biochemistry · Uric Acid Metabolism

Disorders in which fluid-filled sacs (cysts) form in the kidneys, ranging from harmless single cysts to inherited disease that destroys kidney function.

Pathology · Cystic Kidney Diseases

Fluids given into a vein to restore blood volume and to correct the body's water and salt balance.

Pharmacology · Fluid & Electrolyte Therapy

A non-cancerous enlargement of the prostate gland in older men that squeezes the urine tube and disturbs the flow of urine.

General Surgery · Prostate Disorders

Stones that form in the urinary tract from crystals in the urine, causing severe colicky pain and blocking the flow of urine.

General Surgery · Urolithiasis

Infection of the urinary system, usually by gut bacteria, common in women, ranging from a bladder infection to a kidney infection.

General Medicine · Urinary Tract Infections

The imaging methods used to examine the kidneys, urinary tract and reproductive organs, each suited to different questions.

Radiology · Genitourinary Imaging

A specialised structure in the kidney that senses blood pressure and salt, and releases renin to defend the circulation.

Physiology · Renal Physiology

The rate at which the kidneys filter fluid from the blood into the tubules, the best overall measure of kidney function.

Physiology · Renal Physiology

An acute, life-threatening complication of insulin deficiency.

General Medicine · Diabetes Mellitus

Chronic high blood glucose from insulin deficiency and/or resistance.

General Medicine · Diabetes Mellitus

T3 and T4 — the master regulators of the body's metabolic rate.

Physiology · Thyroid Gland

Powerful anti-inflammatory and immunosuppressive drugs that mimic cortisol.

Pharmacology · Adrenal Cortex Hormones

The hormone (and injectable drug) that lowers blood glucose.

Pharmacology · Pancreatic Hormones

An under-active versus over-active thyroid gland.

General Medicine · Thyroid Disorders

A common hormonal disorder causing irregular ovulation.

Obstetrics & Gynaecology · Polycystic Ovary Syndrome

Drugs used to lower blood glucose in diabetes mellitus.

Pharmacology · Diabetes Mellitus

Weight gain or growth that is slower than expected in a child.

Pediatrics · Growth Disorders

Reading TSH with free T4 to classify thyroid status.

Pathology · Thyroid Function Tests

How parathyroid hormone, active vitamin D and calcitonin keep the ionised plasma calcium inside a narrow range.

Physiology · Calcium Metabolism

The body's storage hormone: how beta cells sense glucose, release insulin, and switch the whole body from breaking down to building up.

Physiology · Insulin Physiology

The anterior pituitary hormone that drives body growth and shifts metabolism towards using fat and sparing glucose.

Physiology · Pituitary Hormones

An endocrine gland in the front of the neck, made of two lobes joined by an isthmus, that wraps around the upper trachea and secretes thyroid hormones.

Anatomy · Thyroid Gland

The main cancers arising from thyroid follicular or C cells, which differ in their cell of origin, microscopic look, way of spreading and outlook.

Pathology · Thyroid Gland

A pair of endocrine glands sitting on top of the kidneys, each with an outer cortex and an inner medulla that make different hormones.

Anatomy · Adrenal Glands

A pea-sized gland hanging beneath the brain that controls many other hormone glands under the direction of the hypothalamus, sitting in a bony hollow of the skull.

Anatomy · Pituitary Gland Anatomy

The back part of the pituitary gland, which stores and releases two hormones made in the hypothalamus: one that saves water and one that acts in childbirth.

Physiology · Pituitary Gland Physiology

The range of harms caused by too little iodine in the diet, from goitre in adults to serious brain damage in the developing baby.

Community Medicine · Nutritional Deficiency Disorders

A group of disorders of chronic high blood glucose caused by defects in insulin secretion, insulin action, or both, leading to widespread tissue damage.

Pathology · Diabetes Mellitus

A tumour of the adrenal medulla that releases catecholamines, causing episodes of high blood pressure, sweating, palpitations and headache.

Pathology · Adrenal Tumours

Drugs that replace thyroid hormone when it is lacking, and drugs that reduce its production when it is in excess.

Pharmacology · Thyroid Pharmacology

Overactivity of the parathyroid glands that raises blood calcium, usually from a benign tumour of one gland.

General Surgery · Parathyroid Disorders

The condition caused by too much of the steroid hormone cortisol, whether from medicines or from the body's own overproduction.

General Medicine · Adrenal Disorders

Disorders of the master gland at the base of the brain, from too much or too little of its hormones, or from pressure by a tumour.

General Medicine · Pituitary Disorders

The foot problems of people with long-standing diabetes, in which nerve damage and poor blood supply lead to ulcers and infection.

General Surgery · Diabetes Complications

How the thyroid gland makes its hormones and how they set the body's metabolic rate.

Physiology · Thyroid Physiology

How the body keeps blood sugar within a narrow range, mainly through the opposing hormones insulin and glucagon.

Physiology · Glucose Homeostasis

The phases of childbirth from onset of contractions to delivery of the placenta.

Obstetrics & Gynaecology · Labour and Delivery

New-onset hypertension with proteinuria after 20 weeks of pregnancy.

Obstetrics & Gynaecology · Hypertensive Disorders of Pregnancy

The ~28-day hormonal cycle that prepares the uterus for pregnancy.

Obstetrics & Gynaecology · Menstrual Cycle

Excessive bleeding after delivery — a leading cause of maternal death.

Obstetrics & Gynaecology · Obstetric Emergencies

Bleeding from the genital tract after 20 weeks and before delivery.

Obstetrics & Gynaecology · Obstetric Hemorrhage

Methods used to prevent unwanted pregnancy.

Obstetrics & Gynaecology · Contraception

A rapid score of a newborn's condition at 1 and 5 minutes of life.

Pediatrics · Neonatal Assessment

The care of a woman and her fetus during pregnancy.

Obstetrics & Gynaecology · Antenatal Care

A pregnancy implanted outside the uterine cavity, usually the fallopian tube.

Obstetrics & Gynaecology · Ectopic Pregnancy

Benign smooth-muscle tumours (leiomyomas) of the uterus.

Obstetrics & Gynaecology · Uterine Pathology

The permanent end of menstruation from loss of ovarian function.

Obstetrics & Gynaecology · Menstrual Disorders

Assessment of a breast lump using triple assessment.

General Surgery · Breast Disorders

A painful, swollen scrotum - exclude testicular torsion first.

General Surgery · Scrotal Disorders

Assessing vaginal bleeding in the first trimester.

Obstetrics & Gynaecology · Early Pregnancy Complications

Time-critical complications around delivery.

Obstetrics & Gynaecology · Obstetric Complications

Choosing drugs safely for a pregnant or breastfeeding patient.

Pharmacology · Drugs in Pregnancy

Reading the cardiotocograph to assess fetal wellbeing in labour.

Obstetrics & Gynaecology · Fetal Monitoring

A structured approach to heavy, irregular or intermenstrual bleeding.

Obstetrics & Gynaecology · Abnormal Uterine Bleeding

The process in the testis that turns diploid stem cells into mature haploid spermatozoa, under hormonal control.

Physiology · Male Reproductive Physiology

A modified skin gland on the chest wall that produces milk, whose blood and especially lymphatic drainage matter greatly in breast cancer.

Anatomy · Breast Anatomy

Cancer arising from the cells of the breast, the commonest cancer in women, classified by where it starts and by the receptors it carries.

Pathology · Breast Tumours

The female sex hormones oestrogen and progesterone, and how they are used in pills that prevent pregnancy.

Pharmacology · Sex Hormones and Contraceptives

Cancers of the testis, the commonest solid cancer in young men, which usually present as a painless lump.

General Surgery · Testis

A placenta that lies low in the womb, covering or close to the outlet, causing painless bleeding late in pregnancy.

Obstetrics & Gynaecology · Placental Disorders

Growths of the ovary, which range widely from harmless cysts to cancer and often grow silently until large.

Obstetrics & Gynaecology · Ovarian Tumours

Cancer of the neck of the womb, strongly linked to a common virus and largely preventable by screening and vaccination.

Obstetrics & Gynaecology · Cervical Cancer

The wide-ranging adjustments the mother's body makes to support the growing baby, affecting almost every organ system.

Obstetrics & Gynaecology · Pregnancy Physiology

The series of passive movements the baby's head makes to pass through the birth canal during a normal labour.

Obstetrics & Gynaecology · Labour and Delivery

The failure of a couple to conceive after a year of regular unprotected intercourse, which can arise from either partner.

Obstetrics & Gynaecology · Infertility

A dropping down of the womb and vaginal walls when their supports weaken, so the pelvic organs bulge toward or out of the vagina.

Obstetrics & Gynaecology · Pelvic Organ Prolapse

A pregnancy in which the mother or baby has a greater than usual chance of harm, needing closer watching.

Obstetrics & Gynaecology · High-Risk Pregnancy

The ways of working out how far a pregnancy has advanced, which guides care and the expected date of delivery.

Obstetrics & Gynaecology · Antenatal Care

A rapid, self-propagating reversal of membrane potential that carries nerve and muscle signals.

Physiology · Neurophysiology

The expected ages for gross-motor, fine-motor, language and social achievements.

Pediatrics · Child Development

An anastomotic ring of arteries at the base of the brain that safeguards its blood supply.

Anatomy · Cerebral Circulation

Twelve paired nerves that arise directly from the brain and brainstem.

Anatomy · Cranial Nerves

An acute focal neurological deficit from interrupted blood flow to the brain.

General Medicine · Cerebrovascular Diseases

The hindbrain structure that coordinates movement, posture and balance.

Anatomy · Cerebellum

Drugs that increase or block the action of acetylcholine.

Pharmacology · Autonomic Pharmacology

Drugs that reversibly block nerve conduction to numb a region.

Anaesthesiology · Local Anaesthetics

The neural pathway that produces an automatic, rapid response to a stimulus.

Physiology · Reflexes

Strong analgesics acting on opioid receptors (e.g. morphine).

Pharmacology · Opioids

Drugs that control seizures by reducing abnormal neuronal firing.

Pharmacology · Antiepileptic Drugs

Seizures triggered by fever in young children, without CNS infection.

Pediatrics · Seizure Disorders

A tendency to recurrent, unprovoked seizures from abnormal brain activity.

General Medicine · Seizure Disorders

A progressive, global decline in cognition that affects daily life.

Psychiatry · Dementia & Cognitive Disorders

Inflammation of the meninges, usually from infection.

General Medicine · CNS Infections

A degenerative disorder from loss of dopamine neurons in the substantia nigra.

General Medicine · Movement Disorders

Drugs used to treat psychosis, mainly by blocking dopamine.

Pharmacology · Antipsychotic Drugs

An acute, fluctuating disturbance of consciousness and attention.

Psychiatry · Delirium & Confusion

Central neuraxial blocks that anaesthetise the lower body.

Anaesthesiology · Regional Anaesthesia

A structured differential of a lump in the neck by site and age.

General Surgery · Neck Masses

The syndrome that follows abrupt reduction of alcohol in a dependent person.

Psychiatry · Alcohol Withdrawal

A seizure lasting over 5 minutes, or repeated seizures without recovery in between.

General Medicine · Seizure Disorders

The skin area (dermatome) and muscle group (myotome) supplied by a single spinal nerve root.

Anatomy · Peripheral Nervous System

The motor and sensory loss patterns of the major upper-limb nerves.

Anatomy · Peripheral Nerve Injuries

Using cerebrospinal fluid results to identify the type of meningitis.

Microbiology · CSF Analysis

The cerebellum does not start movement; it compares the movement you intended with the movement you are making and corrects the difference.

Physiology · Cerebellum

A paired dural venous sinus beside the body of the sphenoid, remarkable for the nerves and the artery that run through and beside it.

Anatomy · Cranial Venous Sinuses

A small region at the base of the brain that links the nervous and endocrine systems and keeps the body's internal conditions stable.

Physiology · Hypothalamus

Pain felt at a site away from its true source, explained by how visceral and skin nerves share pathways in the spinal cord.

Physiology · Pain Pathways

A set of connected fluid-filled cavities inside the brain that make and hold cerebrospinal fluid, comprising two lateral ventricles, a third and a fourth ventricle.

Anatomy · Neuroanatomy

The bundles of nerve fibres running up and down the spinal cord that carry sensation to the brain and movement commands from it.

Physiology · Spinal Cord

A group of deep brain nuclei that fine-tune movement, smoothing and scaling voluntary actions and holding back unwanted ones.

Physiology · Basal Ganglia

A compact band of white matter deep in the brain through which most of the nerve fibres travelling to and from the cortex pass.

Anatomy · Internal Capsule

The largest part of the brain, divided into two hemispheres and four lobes, whose surface holds the areas for movement, sensation, vision, hearing and language.

Anatomy · Cerebrum

Specialised nerve endings that detect a stimulus such as touch, heat or light and convert it into electrical signals the nervous system can read.

Physiology · Sensory Receptors

The part of the nervous system that automatically controls internal organs, glands and vessels, through two divisions that usually balance the body's activity.

Physiology · Autonomic Nervous System

A stretch sensor inside skeletal muscle that drives a reflex contraction and helps the body sense and control muscle length and posture.

Physiology · Reflexes

Valveless venous channels between the layers of the dura mater that collect blood from the brain and drain it towards the internal jugular veins.

Anatomy · Cranial Venous Sinuses

The largest nerve in the body, which supplies the back of the thigh and, through its branches, most of the leg and foot, and is vulnerable to injury in the buttock.

Anatomy · Peripheral Nerves

The lowest part of the brainstem, joining the brain to the spinal cord, that houses the vital centres controlling breathing, heartbeat and blood pressure.

Anatomy · Brainstem

The named holes in the floor of the skull through which nerves and vessels pass between the brain and the rest of the head and body.

Anatomy · Skull Base

The main nerve of the perineum, carrying movement, sensation and control of the pelvic outlet, including the muscles that hold in urine and faeces.

Anatomy · Peripheral Nerves

The seventh cranial nerve, which moves the muscles of facial expression and carries taste and tear and saliva signals, taking a long winding course.

Anatomy · Cranial Nerves

Drugs that raise dopamine activity (and reduce the relative cholinergic activity) in the brain to relieve the stiffness, tremor and slowness of Parkinson's disease.

Pharmacology · Parkinsonism Therapy

Drugs that relieve depression mainly by raising the levels of the monoamine transmitters serotonin and noradrenaline at brain synapses.

Pharmacology · Antidepressant Drugs

Drugs that calm and promote sleep, mostly by enhancing the action of the brain's main inhibitory transmitter, GABA.

Pharmacology · Sedative-Hypnotics

Bacterial pus-forming inflammation of the meninges covering the brain and spinal cord, a serious infection with a typical cerebrospinal fluid picture.

Pathology · Central Nervous System Infections

Growths within the brain and spinal cord, which behave differently from tumours elsewhere because they are enclosed in the rigid skull.

Pathology · Central Nervous System Tumours

The tenth cranial nerve, the longest cranial nerve, which carries parasympathetic fibres to the chest and abdomen and supplies the throat and voice box.

Anatomy · Cranial Nerves

A large egg-shaped mass of grey matter deep in the brain that relays almost all sensory and motor information on its way to the cerebral cortex.

Anatomy · Diencephalon

The short uppermost part of the brainstem that connects the forebrain to the pons and carries pathways for eye movement, hearing and reflexes.

Anatomy · Brainstem

The cord of nervous tissue running in the vertebral canal that links the brain to the body's nerves and carries out reflexes.

Anatomy · Spinal Cord

A space behind the upper jaw that houses the muscles that move the jaw, along with important nerves and vessels.

Anatomy · Craniofacial Spaces

Drugs that produce a reversible loss of consciousness and sensation for surgery, given as gases to breathe or injected into a vein.

Pharmacology · General Anaesthetics

The spinal nerve roots that supply key muscles and reflexes, used to locate the level of a nerve injury.

Anatomy · Spinal Cord & Nerve Roots

Drugs that block the muscarinic actions of acetylcholine, used to dry secretions, relax smooth muscle and speed the heart.

Pharmacology · Autonomic Pharmacology

Drugs used to stop a migraine attack once it starts, and others taken regularly to make attacks less frequent.

Pharmacology · Headache and Migraine

A disease in which the immune system attacks the insulating sheath of nerves in the brain and spinal cord, causing scattered neurological problems.

General Medicine · Demyelinating Diseases

Injury to the head that can damage the brain, ranging from mild concussion to dangerous bleeding inside the skull.

General Surgery · Head Injury

Neurological conditions that produce too much or too little movement, from tremor and jerks to slowness and stiffness.

General Medicine · Movement Disorders

Drugs that reduce muscle spasm and stiffness by acting on the brain and spinal cord, rather than on the muscle itself.

Anaesthesiology · Muscle Relaxants

The main pathway carrying commands for voluntary movement from the brain's motor cortex to the muscles.

Physiology · Motor Pathways

Inflammation of the middle ear, very common in young children.

ENT · Ear Infections

Clouding of the lens causing painless, progressive loss of vision.

Ophthalmology · Lens Disorders

Optic-nerve damage, usually linked to raised intraocular pressure.

Ophthalmology · Glaucoma

Bleeding from the nose — usually minor but occasionally serious.

ENT · Nasal Disorders

The two fundamental types of hearing loss, told apart at the bedside.

ENT · Hearing

Microvascular damage to the retina from long-standing diabetes.

Ophthalmology · Retinal Disorders

Inflammation of the conjunctiva — the common 'red eye'.

Ophthalmology · Conjunctiva

Inflammation of the palatine tonsils, common in children.

ENT · Tonsils

An illusion of movement, usually from an inner-ear (vestibular) problem.

ENT · Vertigo

The eye fails to focus light sharply on the retina.

Ophthalmology · Refractive Errors

Separation of the retina from the underlying layer — an eye emergency.

Ophthalmology · Retinal Disorders

A leading cause of preventable childhood blindness.

Ophthalmology · Nutritional Eye Disorders

Inflammation of the paranasal sinus mucosa, usually after a viral cold.

ENT · Nasal & Sinus Disorders

An inner-ear disorder from excess endolymph (endolymphatic hydrops).

ENT · Vestibular Disorders

Degeneration of the central retina (macula), the leading cause of central vision loss in the elderly.

Ophthalmology · Retinal Disorders

Inflammation of the uveal tract (iris, ciliary body, choroid).

Ophthalmology · Uvea & Uveitis

A common presentation with causes ranging from trivial to sight-threatening.

Ophthalmology · Ocular Emergencies

Inflammation of the external ear canal (swimmer's ear).

ENT · Ear Infections

A change in voice; persistent hoarseness can signal laryngeal cancer.

ENT · Laryngeal Disorders

Abnormal keratinising squamous epithelium in the middle ear that erodes bone.

ENT · Ear Disorders

An ophthalmic emergency that needs rapid triage.

Ophthalmology · Ophthalmic Emergencies

Assessing and protecting the injured eye.

Ophthalmology · Ocular Trauma

Distinguishing a self-limiting sore throat from dangerous causes.

ENT · ENT Emergencies

Working out the cause of ear pain, including referred pain.

ENT · Otalgia

Six numbered embryonic arches of the head and neck; the fifth is rudimentary or absent, so the clinically important arches are 1, 2, 3, 4 and 6, each with its own nerve, cartilage, artery and muscles.

Anatomy · Head and Neck Embryology

Sternocleidomastoid divides each side of the neck into an anterior and a posterior triangle, each further subdivided.

Anatomy · Neck Anatomy

A muscular organ of taste, speech and swallowing, split by a V-shaped groove into an oral and a pharyngeal part with different nerve supplies.

Anatomy · Oral Cavity

The chain of nerves that carries signals from the retina to the visual cortex, arranged so that each side of the brain sees the opposite half of the world.

Physiology · Visual Pathway

The organ of voice in the neck, a framework of cartilages that guards the airway during swallowing and produces sound by vibrating the vocal folds.

Anatomy · Larynx

A pair of lymphoid masses in the side walls of the throat that help defend against inhaled and swallowed germs, forming part of a protective ring.

Anatomy · Tonsils

The air-filled chamber that turns sound vibrations in air into stronger vibrations in the fluid of the inner ear, using three tiny bones.

Physiology · Hearing and Ear

The pouches lining the inside of the developing throat between the pharyngeal arches, which form several important head and neck structures.

Anatomy · Pharyngeal Apparatus

Drugs that lower the raised pressure inside the eye in glaucoma, either by making less fluid or by draining more.

Pharmacology · Glaucoma Pharmacology

The cone-shaped bony socket that holds and protects the eyeball, formed by several skull bones.

Anatomy · Orbit & Eye Anatomy

The air-filled spaces in the skull bones around the nose that lighten the skull and open into the nasal cavity.

Anatomy · Nasal Cavity & Sinuses

An open sore on the clear front window of the eye, usually from infection, which threatens sight if it scars the cornea.

Ophthalmology · Cornea

Sudden blockage of the artery or vein of the retina, an important cause of sudden painless loss of vision.

Ophthalmology · Retina

The patterns of lost vision that follow damage at different points along the visual pathway, used to locate the problem.

Ophthalmology · Visual Pathways

Inflammation of the middle, pigmented layer of the eye, which causes a painful red eye and can threaten sight.

Ophthalmology · Uvea

The changes in the retina caused by long-standing high blood pressure, seen when the back of the eye is examined.

Ophthalmology · Retina

An inherited disease in which the light-sensing cells of the retina slowly die, causing night blindness and shrinking vision.

Ophthalmology · Retina

Misalignment of the eyes and the lazy eye that can result when the brain suppresses the image from one eye in childhood.

Ophthalmology · Ocular Motility

A serious infection of the tissues within the eye socket, often spreading from the sinuses, that threatens sight and life.

Ophthalmology · Orbit

Infection of the tear sac, usually because the tear duct is blocked, causing a watering eye and a swelling at the inner corner.

Ophthalmology · Lacrimal Apparatus

A recurring allergic inflammation of the surface of the eye, common in boys and worse in warm, dry seasons.

Ophthalmology · Conjunctiva and Cornea

Wasting of the optic nerve fibres, seen as a pale optic disc, causing a loss of vision that cannot be reversed.

Ophthalmology · Optic Nerve Disorders

Damage to the optic nerve from poisons or from a lack of key nutrients, causing a gradual, painless loss of central vision in both eyes.

Ophthalmology · Optic Nerve Disorders

The thin layer of fluid that coats the front of the eye to keep it smooth, moist and protected, and the trouble caused when it fails.

Ophthalmology · Tear Film and Dry Eye

Common conditions of the eyelids, including infections, lumps and problems with their position.

Ophthalmology · Eyelid Disorders

How blindness and low vision are defined by the level of sight, and the main causes worldwide, many of which are preventable.

Ophthalmology · Blindness and Visual Impairment

The methods used to look at the back of the eye (the fundus), including the optic disc, retina and vessels.

Ophthalmology · Fundus Examination

Enlargement of the lymphoid tissue at the back of the nose in children, which can block the nose and the ear tubes.

ENT · Adenoids and Tonsils

Two common causes of a blocked nose: soft swellings of the nasal lining, and a bent partition between the nostrils.

ENT · Nasal Obstruction

The changes in the eyes that reflect diseases of the whole body, making the eye a window on general health.

Ophthalmology · Ocular Manifestations of Systemic Disease

The layered make-up of the eyeball, whose three coats and clear contents work together to form an image.

Ophthalmology · Anatomy of the Eye

A network of nerves (roots C5–T1) that supplies the upper limb.

Anatomy · Upper Limb Anatomy

A triangular space in the upper thigh containing major neurovascular structures.

Anatomy · Lower Limb Anatomy

The staged biological process by which bone repairs itself.

Orthopaedics · Bone Healing

A surgical emergency where raised pressure within a fascial compartment cuts off perfusion.

Orthopaedics · Compartment Syndrome

The synapse where a motor neuron signals a skeletal muscle fibre to contract.

Physiology · Neuromuscular Junction

Non-steroidal anti-inflammatory drugs that block cyclooxygenase (COX).

Pharmacology · NSAIDs

A degenerative 'wear-and-tear' disease of synovial joints.

Orthopaedics · Arthritis

A chronic, immune-mediated skin disease with rapid skin-cell turnover.

Dermatology · Psoriasis

The narrow passage at the wrist through which the median nerve and flexor tendons run.

Anatomy · Upper Limb Anatomy

Tissue injury from heat, chemicals, electricity or radiation.

General Surgery · Burns

A chronic, itchy, relapsing inflammatory skin disease, part of the atopic triad.

Dermatology · Eczematous Disorders

A malignant tumour of melanocytes — the most dangerous skin cancer.

Dermatology · Skin Malignancies

A common disorder of the pilosebaceous (hair-oil gland) units.

Dermatology · Acne & Sebaceous Disorders

A break in the continuity of a bone.

Orthopaedics · Fractures

Reduced bone mass and density, raising the risk of fracture.

Orthopaedics · Osteoporosis

Soft, weak bones from defective mineralisation (vitamin D deficiency).

Orthopaedics · Metabolic Bone Disease

A chronic autoimmune inflammatory arthritis of the small joints.

General Medicine · Inflammatory Arthritis

Infection of bone, usually bacterial (often Staphylococcus aureus).

Orthopaedics · Bone Infections

Arthritis caused by deposition of monosodium urate crystals.

General Medicine · Crystal Arthropathies

An intensely itchy skin infestation by the mite Sarcoptes scabiei.

Dermatology · Parasitic Skin Diseases

Drugs that block neuromuscular transmission to relax skeletal muscle.

Anaesthesiology · Neuromuscular Blockade

Transient itchy wheals (urticaria) and deeper swelling (angioedema) from mast-cell mediator release.

Dermatology · Urticaria & Angioedema

Two autoimmune blistering diseases distinguished by the level of the split.

Dermatology · Autoimmune Blistering Diseases

Infection within a joint - an orthopaedic emergency.

Orthopaedics · Joint Infections

Herniation of the nucleus pulposus compressing a nerve root.

Orthopaedics · Spine Disorders

The vocabulary to describe rashes and lesions accurately.

Dermatology · Skin Lesions

A structured approach to the itchy patient.

Dermatology · Pruritus

Separating benign mechanical back pain from sinister causes.

Orthopaedics · Back Pain

An age-based approach to the child who will not weight-bear.

Orthopaedics · Pediatric Orthopaedics

Working through the differential of a lump in the groin.

General Surgery · Groin Lump

Distinguishing the common causes of a chronic leg ulcer.

General Surgery · Leg Ulcers

Spotting the rashes that signal a life-threatening illness.

Dermatology · Emergency Rash

The largest synovial joint in the body, a modified hinge between femur, tibia and patella allowing flexion, extension and slight rotation.

Anatomy · Lower Limb Joints

A ball-and-socket synovial joint between the head of the femur and the acetabulum, built for stability and weight-bearing.

Anatomy · Lower Limb Joints

A ball-and-socket synovial joint between the head of the humerus and the shallow glenoid cavity of the scapula, built for a huge range of movement.

Anatomy · Upper Limb Joints

Growths arising in bone, ranging from harmless benign lesions to aggressive malignant cancers, often recognised by the patient's age and the bone site.

Pathology · Bone Tumours

How a nerve signal makes a skeletal muscle shorten, by calcium letting the protein filaments slide over one another and pull using energy from ATP.

Physiology · Skeletal Muscle

A funnel of fascia that carries the main vessels from the abdomen into the thigh, with a small medial space that is the site of a femoral hernia.

Anatomy · Femoral Region

The diamond-shaped hollow behind the knee, a crossroads for the main nerves and vessels passing between the thigh and the leg.

Anatomy · Knee Region

The curved arrangements of the foot bones that spread body weight, absorb shock and give the spring needed for standing and walking.

Anatomy · Foot Anatomy

A firm but flexible connective tissue that cushions joints, shapes the airway and ear, and serves as a model for growing bone, in three main types.

Anatomy · Cartilage

The two commonest skin cancers, both linked to sun exposure, which arise from cells of the epidermis and uncommonly metastasise.

Pathology · Skin Tumors

The general plan of a vertebra and how it changes along the spine to suit the different jobs of the neck, chest and lower back.

Anatomy · Vertebral Column

The buttock region behind the pelvis, made of the gluteal muscles and crossed by nerves and vessels, and a common site for injections.

Anatomy · Gluteal Region

The most abundant protein in the body, a strong triple-stranded rope that gives skin, bone, tendon and blood vessels their tensile strength.

Biochemistry · Collagen

The pyramid-shaped space of the armpit that lets the main nerves and vessels pass between the neck and the arm.

Anatomy · Upper Limb Anatomy

The triangular hollow in front of the elbow, a crossing point for the main artery, nerves and a tendon of the arm.

Anatomy · Upper Limb Anatomy

Diseases that weaken bone throughout the body by upsetting its mineral content or the balance between its building and breakdown.

Pathology · Metabolic Bone Disorders

The hinge joint between the arm and forearm, where three bones meet, allowing bending and straightening of the arm.

Anatomy · Upper Limb Anatomy

The joint between the forearm and the hand and the small carpal bones that make it, allowing the many movements of the wrist.

Anatomy · Upper Limb Anatomy

Drugs that slow the joint damage of rheumatoid arthritis by damping the overactive immune process, not just easing pain.

Pharmacology · Pharmacology of Rheumatic Diseases

A locally aggressive bone tumour of young adults, typically at the end of a long bone near a joint.

General Surgery · Bone Tumours

A small, benign bone tumour of young people that causes a characteristic night pain relieved by simple pain-killers.

General Surgery · Bone Tumours

Ways of covering a wound that cannot be closed directly, by moving skin from one place to another.

General Surgery · Wound Management

Common infections of the fingers and hand, whose enclosed spaces make even small infections painful and potentially serious.

General Surgery · Hand Infections

A common birth deformity of the foot in which it is turned downward and inward, best corrected early in life.

Orthopaedics · Congenital Foot Deformities

A condition present in early life in which the hip joint is poorly formed, so the ball can slip out of a shallow socket.

Orthopaedics · Pediatric Hip Disorders

The problems that can follow a broken bone, either early and dangerous or late and affecting healing and function.

Orthopaedics · Fractures

The ways broken bones are described and grouped by the shape of the break and whether the skin is broken.

Orthopaedics · Fractures

Displacement of the ball of the hip from its socket, usually from a strong force, most often pushing it backward.

Orthopaedics · Hip Injuries

Injuries to the ligaments and cartilage of the knee that are common in sports, causing pain, swelling and instability.

Orthopaedics · Knee Injuries

Displacement of the ball of the shoulder from its shallow socket, the most commonly dislocated large joint.

General Surgery · Shoulder Injuries

A common childhood fracture just above the elbow, important because it can injure the nearby artery and nerves.

General Surgery · Upper Limb Injuries

Loss of hair, which may be patchy or diffuse, scarring or non-scarring, and which has many different causes.

Dermatology · Hair Disorders

An intensely itchy, blistering skin disease strongly linked to coeliac disease and sensitivity to gluten.

Dermatology · Immunobullous Disorders

Disorders in which the skin loses or gains pigment, changing its colour in patches, with important social effects.

Dermatology · Pigmentary Disorders

Severe, life-threatening skin reactions, usually to drugs, in which the skin blisters and peels off in sheets.

Dermatology · Severe Drug Reactions

A common, self-limiting rash of young people that starts with a single patch and then spreads in a typical pattern.

Dermatology · Papulosquamous Disorders

Common skin infections caused by viruses, including warts from the papillomavirus and the blisters of herpes.

Dermatology · Viral Skin Infections

Infections of the skin by bacteria, ranging from surface impetigo to deeper, spreading cellulitis.

Dermatology · Bacterial Skin Infections

Two of the commonest harmless lumps under the skin, distinguished by their feel and their features.

General Surgery · Benign Skin Tumors

The imaging methods used to examine bones, joints and soft tissues, from plain X-rays to MRI.

Radiology · Musculoskeletal Imaging

How a nerve signal is passed to a muscle at the neuromuscular junction, causing the muscle to contract.

Physiology · Neuromuscular Physiology

The features that separate a benign growth from a cancer.

Pathology · Neoplasia

Pathological clot formation inside an intact blood vessel.

Pathology · Thrombosis

Drugs that reduce the blood's ability to clot.

Pharmacology · Anticoagulants

A reduction in haemoglobin or red-cell mass below normal.

General Medicine · Anaemia

Extracellular deposition of misfolded 'amyloid' protein that damages organs.

Pathology · Amyloidosis

Cytotoxic drugs that preferentially kill rapidly dividing cells.

Pharmacology · Cancer Chemotherapy

Red-cell antigens that determine blood-transfusion compatibility.

Physiology · Blood Groups

The commonest cancer in women, usually a ductal carcinoma.

General Surgery · Breast Cancer

The chain of clotting factors that forms a stable fibrin clot.

Physiology · Hemostasis

Substances (often in blood) associated with particular cancers.

Pathology · Tumor Markers

Primary and secondary neoplasms of bone.

Orthopaedics · Bone Tumours

How the aggressiveness and spread of a cancer are described.

Pathology · Cancer Staging & Grading

Reading the complete blood count to spot common problems.

Pathology · Full Blood Count

Safe use of blood products and recognising transfusion reactions.

Anaesthesiology · Blood Transfusion

Reading the PT, APTT and related coagulation tests.

Pathology · Coagulation Tests

Using ferritin, iron, transferrin and saturation to classify anaemia.

Pathology · Iron Studies

Anaemia caused by shortened red cell survival, classified by where the cells are destroyed and by whether the cause is immune.

Pathology · Hemolytic Anemia

How the marrow turns a stem cell into a red blood cell, what it needs to do it, and what tells it to speed up.

Physiology · Erythropoiesis

How the body builds haem step by step, and how blocks in that pathway cause the porphyrias.

Biochemistry · Haem Synthesis

A framework that sorts anaemia by red-cell size (the MCV) into microcytic, normocytic and macrocytic, pointing to the likely cause.

Pathology · Anaemia Classification

The body's blood-cell factory, and the ways it changes when the body needs more cells or when disease invades it.

Pathology · Bone Marrow

A stained film of blood whose cell shapes and inclusions give morphological clues that help narrow the differential of anaemia and other blood disorders.

Pathology · Anaemia Diagnosis

Enlargement of the spleen, grouped by the mechanism that drives it, from congestion to infiltration to overwork.

Pathology · Spleen Disorders

How the body absorbs, transports, stores and recycles iron, a metal needed for haemoglobin but toxic in excess, so its level is tightly controlled.

Biochemistry · Iron Metabolism

The proteins dissolved in blood plasma, chiefly albumin and the globulins, which carry substances, defend the body, clot blood and hold fluid in the vessels.

Biochemistry · Plasma Proteins

A group of blood cancers in which abnormal white cells multiply in the bone marrow and blood, crowding out normal cells; grouped as acute or chronic and myeloid or lymphoid.

Pathology · Leukaemia

A cancer of lymphoid tissue characterised by Reed-Sternberg cells in a reactive background, which usually starts in one group of lymph nodes and spreads in an orderly way.

Pathology · Lymphoma

The multi-step process by which normal cells become cancerous through accumulated changes in the genes that control growth, death and repair.

Pathology · Carcinogenesis

The smallest blood cells, really cell fragments, that plug damaged vessels and start the clotting process to stop bleeding.

Physiology · Platelets

The iron-containing protein in red cells that carries oxygen, built from four globin chains each holding a haem group with one iron atom.

Physiology · Haemoglobin

What can happen to a blood clot after it forms inside a vessel, ranging from harmless dissolving to breaking off and blocking a distant vessel.

Pathology · Thrombosis

Conditions in which blood fails to clot properly, causing easy or prolonged bleeding, from either a platelet problem or a clotting-factor problem.

Pathology · Bleeding Disorders

The rules used to name tumours, which usually reveal both the tissue a tumour came from and whether it is benign or malignant.

Pathology · Neoplasia

Enlargement of lymph nodes, which may be a harmless reaction to a nearby infection or a sign of a blood cancer or a spreading tumour.

Pathology · Lymphadenopathy

The harmful reactions that can follow a blood transfusion, ranging from mild fever to a dangerous destruction of the transfused red cells.

Pathology · Blood Transfusion

Cell changes that can occur on the path towards cancer - one mature cell type replacing another, disordered growth, and a contained early cancer - though they do not always progress.

Pathology · Precancerous Changes

A cancer of the plasma cells in the bone marrow, which flood the blood with one useless antibody and eat away at the bones.

Pathology · Plasma Cell Disorders

The two opposing classes of genes whose mutation drives cancer: accelerators that are switched on and brakes that are switched off.

Biochemistry · Cancer Genetics

Abnormal immunoglobulin proteins made by a single clone of plasma cells, detected in blood and urine in disorders such as myeloma.

Biochemistry · Plasma Cell Disorders

Effects of cancer felt away from the tumour itself, caused by substances it releases or by immune reactions, including severe weight loss.

Pathology · Paraneoplastic Syndromes

The features of a cancer that forecast its likely outcome (prognostic) or its likely response to a particular treatment (predictive).

Pathology · Cancer Prognosis and Prediction

Anaemia caused by a lack of the nutrients needed to make red blood cells, chiefly iron, and the public-health measures against it.

Community Medicine · Nutritional Anaemia

Changes in tissue that carry an increased risk of turning into cancer, which are watched or removed to prevent it.

General Surgery · Neoplasia

A blood clot in a deep vein, usually of the leg, which can break off and travel to the lungs.

General Surgery · Venous Thromboembolism

An inherited disorder in which abnormal haemoglobin makes red cells sickle-shaped, blocking small vessels and breaking down.

General Medicine · Hemoglobinopathies

How the body stops bleeding from a damaged vessel, through the actions of vessels, platelets and clotting proteins.

Physiology · Hemostasis and Coagulation

Exaggerated or inappropriate immune responses, classified Types I–IV.

Microbiology · Hypersensitivity

The routine vaccine schedule that protects children from key infections; schedules vary by country, and this one follows India's National Immunization Schedule.

Pediatrics · Vaccination

The five antibody classes and their distinct roles.

Microbiology · Antibodies

An organised collection of macrophages formed in chronic inflammation.

Pathology · Chronic Inflammation

Preparations that stimulate protective immunity against a pathogen.

Microbiology · Vaccines

Prolonged inflammation with simultaneous tissue destruction and repair.

Pathology · Inflammation

Indirect protection of a population when a high proportion is immune.

Community Medicine · Immunity

A severe, rapid-onset systemic hypersensitivity reaction.

General Medicine · Hypersensitivity Reactions

The body's largest lymph vessel, which drains lymph from most of the body into the bloodstream at the root of the neck on the left side.

Anatomy · Lymphatic System

The body's two-tier defence system: a fast, general innate response and a slower, specific adaptive response that remembers past invaders.

Physiology · Immunity

The largest secondary lymphoid organ, sitting in the upper left abdomen, which filters blood, recycles old red cells and helps fight infection.

Anatomy · Lymphoid Organs

A cascade of blood proteins that helps the immune system destroy microbes by tagging them, punching holes in them and calling in inflammation.

Microbiology · Complement System

A set of cell-surface molecules, called HLA in humans, that display fragments of proteins to the immune system and strongly influence transplant compatibility.

Microbiology · Antigen Presentation

A disease of unknown cause in which clumps of immune cells (non-caseating granulomas) form in many organs, most often the lungs and lymph nodes.

Pathology · Granulomatous Diseases

An autoimmune disease in which the body makes antibodies against its own tissues, damaging the skin, joints, kidneys and many other organs.

Pathology · Autoimmune Diseases

Drugs that damp down the immune system to prevent transplant rejection and to treat diseases where immunity attacks the body.

Pharmacology · Immunosuppressive Drugs

Drugs that block the actions of histamine, a chemical released in allergy, used for itch, hay fever and hives.

Pharmacology · Antihistamines

Infection with a virus that attacks the immune system, leaving the body open to unusual infections and cancers.

General Medicine · HIV and AIDS

A group of diseases in which blood vessels become inflamed, damaging the organs they supply, grouped by vessel size.

General Medicine · Vasculitis

Antibiotics grouped by their mechanism of action.

Pharmacology · Antimicrobials

A differential stain that classifies bacteria by their cell-wall structure.

Microbiology · Bacteriology

The acid-fast bacillus that causes tuberculosis.

Microbiology · Bacteria

A protozoal disease caused by Plasmodium, spread by the female Anopheles mosquito.

Microbiology · Protozoa

The two major groups of Gram-positive cocci, told apart at the bench.

Microbiology · Gram-Positive Cocci

Two different levels of removing microbes from instruments and surfaces.

Microbiology · Sterilisation & Disinfection

Life-threatening organ dysfunction from a dysregulated response to infection.

General Medicine · Sepsis

A superficial fungal infection of skin, hair or nails.

Dermatology · Superficial Fungal Infections

A chronic infection by Mycobacterium leprae affecting skin and nerves.

Dermatology · Leprosy

A retrovirus that destroys CD4 T-cells, causing progressive immunodeficiency.

Microbiology · HIV/AIDS

When microbes evolve to survive drugs that once killed them.

Microbiology · Antimicrobial Resistance

A systemic infection by Salmonella Typhi or Paratyphi spread by the faeco-oral route.

Microbiology · Enteric Infections

A mosquito-borne flavivirus infection transmitted by Aedes aegypti.

Microbiology · Arboviral Infections

Diseases caused by spore-forming anaerobic Clostridium species.

Microbiology · Anaerobic Infections

Interpreting the blood markers of hepatitis B infection.

Microbiology · Hepatitis Viruses

A near-universally fatal viral encephalitis transmitted by animal bites.

Microbiology · Rabies and Lyssaviruses

Using antibiotics responsibly to preserve their effectiveness.

Pharmacology · Antibiotic Use

Approaching fever after recent foreign travel.

Microbiology · Fever Syndromes

Infections acquired during healthcare that were not present on admission.

Microbiology · Nosocomial Infections

The immediate steps after a sharps or body-fluid exposure.

Microbiology · Needlestick Injury

The study of fungi that cause human disease, which range from surface skin infections to life-threatening infections in people with weak immunity.

Microbiology · Fungi

The two great groups of viruses, classified by whether their genetic material is DNA or RNA, which shapes how they copy themselves and cause disease.

Microbiology · Viruses

The parts that make up a bacterial cell and the way bacteria multiply, which explain how they cause disease and how we can kill them.

Microbiology · Bacteria

The parasitic worms that infect humans, divided into flatworms and roundworms, which cause much disease worldwide, especially where sanitation is poor.

Microbiology · Helminths

A group of unusual bacteria that are hard to see or grow by ordinary methods, and that cause diseases such as syphilis, typhus and atypical pneumonia.

Microbiology · Atypical Bacteria

A large family of gram-negative rods living in the gut, including harmless residents and important causes of diarrhoea, urine and bloodstream infections.

Microbiology · Enterobacteriaceae

Single-celled eukaryotic organisms, many of which are parasitic and cause human disease, spread through contaminated food and water, insect bites or sexual contact.

Microbiology · Protozoa

The slow-growing acid-fast bacterium that causes leprosy, a chronic infection of the skin and nerves that can lead to deformity if not recognised.

Microbiology · Mycobacteria

The nutrient jellies and broths used to grow microbes in the laboratory, and the main ways bacteria are identified from a specimen.

Microbiology · Laboratory Diagnosis

A group of rod-shaped gram-positive bacteria whose powerful toxins cause diphtheria, anthrax, tetanus, botulism and gas gangrene.

Microbiology · Gram-Positive Bacteria

The different ways an infectious agent passes from its source to a new host, which shape how each disease spreads and is prevented.

Community Medicine · Transmission of Infection

The ways of preventing diseases spread by insects and other vectors, by attacking the vector, protecting people, or both.

Community Medicine · Vector-Borne Diseases

Drugs used against the malaria parasite, which act at different stages of its life cycle inside the red cells and the liver.

Pharmacology · Antimalarial Therapy

Drugs that kill the slow-growing tuberculosis bacillus, used together in combinations to prevent resistance.

Pharmacology · Antitubercular Therapy

A large family of beta-lactam antibiotics, grouped into generations that broadly shift from Gram-positive cover towards Gram-negative and hospital organisms.

Pharmacology · Antibacterial Drugs

Infections spread by drinking contaminated water or eating contaminated food, a major cause of diarrhoea and outbreaks.

Community Medicine · Water- and Food-Borne Infections

Methods that reduce or remove germs from objects and surfaces to prevent the spread of infection.

Community Medicine · Infection Control

The large family of antibiotics built around the beta-lactam ring, which kill bacteria by wrecking their cell wall.

Pharmacology · Beta-Lactam Antibiotics

Drugs that kill single-celled parasites and anaerobic bacteria, with metronidazole the best-known example.

Pharmacology · Antiprotozoal Drugs

The use of drugs to prevent a disease in a person who is at risk but not yet ill.

Pharmacology · Prevention of Infectious Diseases

Drugs that kill or stop fungi, targeting parts of the fungal cell that human cells do not have.

Pharmacology · Antifungal Drugs

Drugs that rid the body of worms by paralysing them or starving them of energy so that they are passed out.

Pharmacology · Anthelmintic Drugs

Drugs that stop viruses from multiplying by blocking steps in their life cycle, since viruses use the host's own cells.

Pharmacology · Antiviral Drugs

A sexually transmitted infection caused by a spiral bacterium, which if untreated passes through several stages over years.

Dermatology · Sexually Transmitted Infections

A mosquito-borne viral illness common in the tropics, causing high fever and body aches, which can turn severe.

General Medicine · Arboviral Infections

A systemic bacterial infection from contaminated food or water, causing a stepwise fever and abdominal symptoms.

General Medicine · Enteric Fever

A common viral infection of the airways that causes seasonal epidemics and, occasionally, worldwide pandemics.

General Medicine · Respiratory Viruses

A chronic infection by the tuberculosis bacillus, most often of the lungs, spread through the air and a major global disease.

General Medicine · Tuberculosis

The common childhood infections that cause a fever with a widespread rash, several of them now prevented by vaccines.

Pediatrics · Childhood Viral Exanthems

A serious bloodstream infection in a newborn baby, whose signs are subtle, needing a high index of suspicion.

Pediatrics · Neonatal Infections

Preventive treatment given soon after a possible exposure to a serious infection, to stop it from taking hold.

General Medicine · Post-Exposure Prophylaxis

A disease caused by Leishmania parasites, spread by sandflies, ranging from skin sores to a deadly disease of the internal organs.

Microbiology · Protozoal Infections

The sequence of changes after death, used to estimate the time since death.

Forensic Medicine · Forensic Pathology

A chronic psychotic disorder affecting thought, perception and behaviour.

Psychiatry · Psychotic Disorders

A persistent low mood and loss of interest that impairs daily function.

Psychiatry · Mood Disorders

Wounds classified by mechanism — central to medico-legal reporting.

Forensic Medicine · Forensic Wounds

Death from interference with the body's oxygen supply.

Forensic Medicine · Asphyxia

A mood disorder alternating between episodes of mania and depression.

Psychiatry · Mood Disorders

Excessive, persistent worry or fear that impairs daily functioning.

Psychiatry · Anxiety Disorders

Bluish-purple discolouration where blood settles under gravity after death.

Forensic Medicine · Postmortem Changes

A postmortem examination to establish the cause and manner of death.

Forensic Medicine · Autopsy

Recurrent intrusive thoughts (obsessions) and repetitive acts (compulsions).

Psychiatry · Obsessive–Compulsive Disorder

A compulsive pattern of harmful alcohol use with tolerance and withdrawal.

Psychiatry · Substance Use Disorders

Wounds produced by projectiles fired from firearms.

Forensic Medicine · Injuries & Wounds

The general approach to a poisoned patient.

Forensic Medicine · Poisoning & Toxicology

The legal duties of consent and the standard of care.

Forensic Medicine · Medical Law & Ethics

Establishing who a deceased person is.

Forensic Medicine · Forensic Identification

Recognising and acting on suspected child abuse.

Pediatrics · Child Protection

A structured snapshot of a patient's mental state at the time of interview.

Psychiatry · Mental State Examination

Assessing and reducing the risk of harm to self or others.

Psychiatry · Risk Assessment

Safe de-escalation and, when needed, rapid tranquillisation.

Psychiatry · Acute Agitation

Judging whether a patient can make a specific decision at a specific time.

Psychiatry · Capacity Assessment

Completing the death certificate accurately and lawfully.

Forensic Medicine · Death Certification

The sensitive, consented and meticulous examination of an alleged assault survivor.

Forensic Medicine · Sexual Assault Examination

Estimating age from teeth and bone for medico-legal purposes.

Forensic Medicine · Age Estimation

Poisoning by metals such as lead, arsenic and mercury, which build up in the body and damage the nerves, gut and other organs.

Forensic Medicine · Toxicology

Poisoning by strong acids or alkalis that burn and destroy the tissues they touch, chiefly the mouth, food pipe and stomach.

Forensic Medicine · Toxicology

Plants that contain natural poisons dangerous to humans, some used in traditional practice, crime or self-harm, each with tell-tale effects.

Forensic Medicine · Toxicology

Poisoning by the colourless, odourless gas carbon monoxide, which starves the tissues of oxygen by taking its place on haemoglobin.

Forensic Medicine · Toxicology

Poisoning by methanol (wood alcohol), often from illicit liquor, which is turned in the body into acids that cause blindness and can kill.

Forensic Medicine · Toxicology

Poisoning by organophosphate insecticides, which block the enzyme that switches off nerve signals, flooding the body with acetylcholine.

Forensic Medicine · Toxicology

Substances taken for their pleasurable or mind-altering effects, which can cause dependence, overdose and death, and are important in forensic work.

Forensic Medicine · Toxicology

An official legal inquiry into a death that is sudden, suspicious or unnatural, held to find out who died and how, when and where.

Forensic Medicine · Forensic Procedures

Injury and poisoning from snake venom, which is broadly either neurotoxic or vasculotoxic depending on the snake.

Forensic Medicine · Toxicology and Poisoning

A rapidly acting poison that stops cells from using oxygen, so the tissues suffocate even though the blood is well oxygenated.

Forensic Medicine · Toxicology and Poisoning

Poisoning by barbiturate sedatives, which deeply depress the brain and breathing and were once a common means of suicide.

Forensic Medicine · Toxicology and Poisoning

The Indian law that sets out when and by whom a pregnancy may be lawfully ended, and that protects a registered doctor who acts within it.

Forensic Medicine · Medical Law and Ethics

The role a doctor plays when giving evidence in court, and the kinds of witness and evidence that the law recognises.

Forensic Medicine · Medical Law and Ethics

A pattern of repeated physical abuse of a young child by a carer, recognised from injuries of different ages that do not match the account given.

Forensic Medicine · Injury and Abuse

The wound features that help decide whether an injury was self-inflicted, caused by another person, or accidental.

Forensic Medicine · Injury and Abuse

The legal grading of bodily injury into simple and grievous hurt, which decides the seriousness of the offence.

Forensic Medicine · Injury and Abuse

Two forms of pressure on the neck that block breathing and blood flow; hanging uses the body's own weight, while strangulation uses another force.

Forensic Medicine · Asphyxial Deaths

The effects of drinking ethanol on the body and behaviour, and how these matter in law, especially for driving.

Forensic Medicine · Alcohol and Law

The bodily changes that show a woman has given birth recently, used in medicolegal questions such as a concealed birth.

Forensic Medicine · Forensic Obstetrics

The unlawful ending of a pregnancy outside the protection of the law, often done unsafely, with serious medicolegal importance.

Forensic Medicine · Criminal Abortion

The patterns of ridges on the fingertips, which are unique to each person and unchanging, making them a powerful means of identification.

Forensic Medicine · Personal Identification

The body that registers doctors and sets the standards of professional conduct, and what happens when those standards are broken.

Forensic Medicine · Medical Ethics and Regulation

The findings that show whether a newborn was born alive and breathed, central to the medicolegal question of infanticide.

Forensic Medicine · Forensic Neonatology

Death from natural disease that happens unexpectedly and quickly in someone who seemed well, a common reason for a medicolegal autopsy.

Forensic Medicine · Forensic Pathology

The features that tell whether a wound was made during life or after death, a key question in forensic examination.

Forensic Medicine · Forensic Wound Analysis

The medicolegal assessment of whether a woman is a virgin, and why the signs are not by themselves proof.

Forensic Medicine · Sexual Offences & Examination

The methods used to estimate how long ago a person died, based on the changes that follow death.

Forensic Medicine · Forensic Pathology

Forms of asphyxia in which breathing is prevented by chest compression or by risky solitary behaviour, rather than by a ligature pulled by another.

Forensic Medicine · Asphyxial Deaths

Incised wounds of the neck, whose features help to decide whether they were self-inflicted, homicidal or accidental.

Forensic Medicine · Injuries of Neck

Wounds caused by shotguns, which fire many small pellets, giving a pattern that changes with the range of firing.

Forensic Medicine · Firearm Injuries

The placing of semen into a woman by means other than intercourse to achieve pregnancy, and the legal issues it raises.

Forensic Medicine · Reproductive Ethics

Injuries from heat, flame or hot liquids, and the forensic questions of how they were caused and whether they happened before or after death.

Forensic Medicine · Thermal Injuries

Conditions that affect how a child develops, learns and behaves, recognised by watching development against expected milestones.

Pediatrics · Developmental Disorders

Long-standing, deeply ingrained patterns of thinking, feeling and behaving that differ markedly from what is expected and cause distress or problems.

Psychiatry · Personality Disorders

Mental disorders in which distress appears as physical symptoms or as a splitting-off of memory and identity, without a physical disease to explain them.

Psychiatry · Somatoform & Dissociative Disorders

The classic model of disease causation and its use in outbreak control.

Community Medicine · Epidemiology Basics

Interventions applied at different points along the natural history of disease.

Community Medicine · Prevention

Terms describing how much disease is present in a population.

Community Medicine · Epidemiology

Testing apparently healthy people to detect disease early.

Community Medicine · Screening

Measures of how well a diagnostic test performs.

Community Medicine · Diagnostic Test Evaluation

The main designs used to study disease and its causes.

Community Medicine · Study Design

Quantifying how much disease is present in a population.

Community Medicine · Disease Frequency Measures

Systematic errors that distort the results of a study.

Community Medicine · Study Validity

The stepwise public-health response to a suspected outbreak.

Community Medicine · Outbreak Investigation

Mandatory reporting of certain diseases to enable public-health action.

Community Medicine · Disease Surveillance

The measures that describe a population's births, deaths and structure.

Community Medicine · Demography

The staged process of testing a new drug for safety and effectiveness, from the laboratory through phases of human trials before it can be used.

Pharmacology · Drug Trials & Regulation

The numbers that show how strongly an exposure is linked to a disease and how much of the disease it accounts for, used to weigh risks.

Community Medicine · Measures of Risk

Statistical tests that judge whether a difference found in a study is likely to be real or could easily have arisen by chance.

Community Medicine · Statistical Inference

The ways of choosing a smaller group to study so that it fairly represents the whole population, letting findings be generalised.

Community Medicine · Sampling & Study Design

How measurements spread out, summarised by an average and a spread, with the bell-shaped normal curve as the most important pattern.

Community Medicine · Descriptive Statistics

The safe handling and disposal of waste generated by hospitals and clinics, sorted by colour-coded bins to protect people and the environment.

Community Medicine · Public Health Practice

The ways of measuring whether a person or a community is well nourished, using body measurements, blood tests, clinical signs and diet history.

Community Medicine · Nutrition Assessment

How epidemiologists decide whether a link between an exposure and a disease is true cause-and-effect or merely a chance or indirect connection.

Community Medicine · Causation in Epidemiology

The branch of public health that protects the health of mothers and children, who are a large and vulnerable part of the population.

Community Medicine · Maternal and Child Health

The planned list of vaccines given to children at set ages to protect them against common dangerous infections.

Community Medicine · Immunisation Programmes

India's public-health programme to find and cure tuberculosis and to cut its spread, using free diagnosis and supervised treatment.

Community Medicine · Tuberculosis Control Programmes

Essential health care made available to all in the community at a cost they and the country can afford, the foundation of a health system.

Community Medicine · Primary Health Care

A World Health Organization approach that helps health workers assess, classify and act on the common illnesses of young children in one simple system.

Pediatrics · Child Health Programs