6 exam-style questions with full mark schemes and model answers. Write your own answer and the AI examiner marks it against the mark scheme.
Learn this properly: The Endocrine SystemAfter eating a large meal, a person's blood glucose concentration rises. A few hours later, during exercise, it falls below normal. The body keeps blood glucose within a narrow range by negative feedback.
Explain how the hormones insulin and glucagon control blood glucose concentration when it rises too high and when it falls too low. (6 marks)
The menstrual cycle is controlled by hormones released from the pituitary gland and the ovaries.
(a) Name the hormone that:
(b) Explain how a rise in oestrogen affects the production of FSH, and why this is useful. (2 marks)
On a hot day, a person sweats a great deal during exercise and does not drink any water. Their blood becomes too concentrated (it has too little water).
Describe and explain how the hormone ADH acts on the kidneys to return the water content of the blood to normal. (3 marks)
The kidneys filter the blood by ultrafiltration and then selective reabsorption. The table shows the concentration of three substances in the blood plasma, in the filtrate (in the Bowman's capsule), and in the urine of a healthy person.
| Substance | In blood plasma / g per 100 cm³ | In filtrate / g per 100 cm³ | In urine / g per 100 cm³ |
|---|---|---|---|
| Protein | 8.0 | 0.0 | 0.0 |
| Glucose | 0.10 | 0.10 | 0.00 |
| Urea | 0.03 | 0.03 | 2.0 |
(a) Using the data, explain why there is no protein in the filtrate. (1 mark)
(b) Glucose is present in the filtrate but not in the urine of a healthy person. Explain why. (2 marks)
The combined oral contraceptive pill contains the hormones oestrogen and progesterone.
Explain how taking the contraceptive pill helps to prevent pregnancy. (2 marks)
Urea is a waste product that is removed from the blood by the kidneys.
Name the organ in which urea is produced from the breakdown of excess amino acids. (1 mark)