As we delve into Option H, we’ll be reviewing human biology concepts at the same time. This first section is about hormonal control. Hormones are chemical messengers secreted by endocrine glands into the blood and transported to specific target cells. They can be steroids (eg progesterone, testosterone, estrogen), proteins (eg insulin, ADH, FSH, LH) and tyrosine derivatives (eg thyroxin).
You need to:-
- Distinguish between the mode of action of steroid and protein hormones.
- Outline the relationship between the hypothalamus and the pituitary gland.
- Explain the control of ADH (vasopressin) secretion by negative feedback.