AQA GCSE Biology 4.5.3 Hormonal Coordination in Humans Exam Questions

About AQA GCSE Biology 4.5.3 Hormonal Coordination in Humans

Hormonal coordination is a large section of AQA Homeostasis and response, examined on Paper 2. It covers the endocrine glands, control of blood glucose and diabetes, hormones in the menstrual cycle, contraception and, for Biology students, the kidney and water balance. Higher tier students also study glucagon, the interaction of reproductive hormones, infertility treatment, and adrenaline and thyroxine. Examiners often ask you to compare type 1 and type 2 diabetes, interpret menstrual cycle hormone graphs, evaluate contraceptive methods and IVF, and explain negative feedback loops.

What you need to know

• 4.5.3.1 Endocrine system Glands secrete hormones directly into the bloodstream to target organs. Effects are slower but act for longer than nervous responses. The pituitary gland is the master gland; others are the pancreas, thyroid, adrenal gland, ovary and testes.
• 4.5.3.2 Blood glucose The pancreas monitors blood glucose. If it is too high, insulin causes glucose to move into cells, and liver and muscle cells convert excess to glycogen. Higher tier: if too low, the pancreas releases glucagon, which converts glycogen back to glucose. Type 1 diabetes: pancreas produces too little insulin, treated with injections. Type 2: cells no longer respond to insulin, treated with diet and exercise; obesity is a risk factor.
• 4.5.3.3 Water and nitrogen balance (Biology only) The kidneys filter blood and selectively reabsorb glucose, some ions and water. Higher tier: excess amino acids are deaminated in the liver to form ammonia, which is converted to urea; ADH from the pituitary makes kidney tubules more permeable to water. Kidney failure is treated by dialysis or transplant.
• 4.5.3.4 Hormones in reproduction Oestrogen (ovaries) and testosterone (testes) cause puberty changes. FSH matures an egg and stimulates oestrogen; LH stimulates ovulation; oestrogen and progesterone maintain the uterus lining. Higher tier: explain how these hormones interact, including oestrogen inhibiting FSH.
• 4.5.3.5 Contraception Hormonal methods: oral pills of oestrogen and progesterone inhibit FSH; injections, implants or patches release progesterone. Non-hormonal methods: condoms and diaphragms, IUDs, spermicide, abstaining around ovulation, and sterilisation.
• 4.5.3.6 Infertility (Higher tier only) FSH and LH in a fertility drug can help a woman become pregnant. IVF involves giving FSH and LH, collecting eggs, fertilising them in a lab and inserting embryos into the uterus. IVF is emotionally and physically stressful, success rates are low, and it can lead to multiple births.
• 4.5.3.7 Negative feedback (Higher tier only) Adrenaline from the adrenal glands increases heart rate and boosts oxygen and glucose delivery for fight or flight. Thyroxine from the thyroid stimulates basal metabolic rate and is controlled by negative feedback via TSH from the pituitary.

Common mistakes in 4.5.3 Hormonal Coordination in Humans

• Confusing glucagon with glycogen. Glucagon is a hormone; glycogen is the storage carbohydrate in liver and muscle.
• Saying insulin turns glucose into glycogen directly. Insulin causes cells to take up glucose and stimulates liver and muscle cells to convert it into glycogen.
• Saying type 2 diabetes means the pancreas makes no insulin. In type 2, body cells no longer respond to insulin.
• Saying hormones travel along nerves. Hormones are carried in the blood to target organs.
• Saying ADH makes urine more dilute. ADH increases water reabsorption, producing a smaller volume of more concentrated urine (Higher tier only).

Try three 4.5.3 Hormonal Coordination in Humans exam-style questions