A researcher measured the concentrations of FSH and LH during part of a menstrual cycle. The researcher also recorded changes in one ovary.
| Day of cycle | FSH concentration in IU/L | LH concentration in IU/L | Observation of the ovary |
|---|---|---|---|
| 2 | 5 | 4 | Egg is immature |
| 8 | 9 | 6 | Egg is maturing |
| 13 | 6 | 32 | Mature egg is still in the ovary |
| 14 | 5 | 14 | Mature egg has been released |
Use the data to explain how FSH and LH coordinate the changes in the ovary from day 2 to day 14.
A second menstrual cycle is monitored. From the start of this cycle, before an egg matures, a substance continuously prevents FSH from acting on the ovary. The substance does not prevent LH from acting.
Predict whether an egg would be released in this cycle. Explain your answer.
85 exam-style questions on AQA GCSE Biology 5.3 Hormonal coordination in humans, covering 5.3.1 Human endocrine system, 5.3.2 Control of blood glucose concentration, 5.3.3 Maintaining water and nitrogen balance in the body, 5.3.4 Hormones in human reproduction, 5.3.5 Contraception, 5.3.6 The use of hormones to treat infertility (HT only), and 5.3.7 Negative feedback (HT only). Each one has a worked solution and a mark scheme showing where the marks go.