Biology - Chemical Coordination and Integration Question with Solution | TestHub
Which is the correct sequence of hormone action through membrane receptors?
I. Physiological responses e.g. ovarian growth.
II. Generation of secondary messenger.
III. Release of an enzyme adenylate cyclase from the receptor site.
IV. Formation of hormone receptor complex e.g. FSH.
V. Biochemical responses
Options:
Answer:
Solution:
The mechanism of action of protein hormones (like FSH) through membrane receptors follows a specific sequence:
First, the hormone binds to its specific receptor on the cell membrane, leading to the formation of a hormone-receptor complex (IV).
This complex activates membrane-bound enzymes such as adenylate cyclase (III).
The activated enzyme catalyzes the formation of a secondary messenger, such as cAMP or , inside the cell (II).
The secondary messenger then triggers a cascade of biochemical responses within the target cell (V).
Finally, these biochemical changes culminate in physiological responses, such as ovarian growth (I).
The correct sequence is IV III II V I.
Answer: IV - III - II - V - I
