Human Anatomy and Physiology
What you must know
Organisation runs from cell to tissue to organ to organ system. Digestion: mechanical and chemical breakdown, enzymes (amylase, protease, lipase) and their pH optima, absorption in the ileum across villi (large surface area, thin epithelium, rich blood supply). Circulation: double circulation, four chambers, valves, the cardiac cycle, the SA node as pacemaker, and structure-to-function links for arteries, veins and capillaries. Gas exchange: alveolar adaptations and the mechanics of ventilation (diaphragm contracts and flattens, ribs rise, volume increases, pressure falls). Excretion: the nephron - ultrafiltration at the glomerulus, selective reabsorption of glucose and most water, and ADH controlling water reabsorption. Coordination: neurone structure, the reflex arc, synapses and neurotransmitters, and hormones including insulin, glucagon, adrenaline, thyroxine and ADH. Homeostasis is maintained by negative feedback: thermoregulation, blood glucose and water balance.
Traps and a worked example
Traps: thinking all arteries carry oxygenated blood (the pulmonary artery does not); naming the right ventricle as the thickest chamber (it is the left); mixing diffusion with active transport in the kidney; confusing breathing with respiration.
Worked example: cardiac output = heart rate x stroke volume. At 70 beats per minute and a stroke volume of 70 mL, output = 4900 mL per minute, about 4.9 litres per minute. Rule of thumb: any rate multiplied by a volume is a simple multiplication - check the units the question asks for before writing the answer.