The unit in one line
Eight human organ systems, from digestion to reproduction, with the disorders MEC added in 2026. 15 of Zoology's 40 questions — the heaviest unit in the subject, almost two questions a chapter.
Read in this order
- Digestive system (9 min) — canal, glands, enzymes, hormones and absorption.
- Respiratory system (9 min) — lung volumes, gas transport, control and disorders.
- Circulatory system (9 min) — the heart and its cycle, the ECG, vessels, blood groups and pressure.
- Excretory system (10 min) — the nephron, urine formation and renal disorders.
- Nervous system (9 min) — brain, nerves, the autonomic system and the nerve impulse.
- Sense organs (10 min) — the eye and the ear. Read after the nervous system.
- Endocrinology (10 min) — glands, hormones and their disorders.
- Reproductive system (11 min) — gametogenesis and the ovarian and menstrual cycles. Read after endocrinology: the cycles are hormone curves.
About 77 minutes in all — two sittings.
How it is asked
Recall is normal values and names: tidal volume, GFR, the cranial nerves, which gland makes which hormone. Understanding is predicting what follows when something changes — a valve stiffens, ADH falls, the LH surge fails. Application is a short patient description ("a child with a swollen neck and slowed growth") that the student must place.
The high-yield physiology sheet is the revision card once the chapters are read.
Then practise
Each system has a chapter test under Practice › Topics. With fifteen marks at stake, this is the unit to re-test most often.