Question

The pituitary gland produces a hormone which controls the amount of water in the body. [5 MARKS]
(a) What is the name of this hormone?
(b) What effect would more of this hormone being produced have on the urine?
(c) Suggest why the body needs to re-absorb more water?
(d) Why are hormonal reactions generally slower than nervous reactions?

Answer 1

a) 1 Mark
b) 1 Mark
c) 1 Mark
d) 2 Marks

(a) Antidiuretic hormone (ADH) controls the amount of water in the body.

(b) More concentrated urine will be produced.

(c) The body needs to re-absorb more water to maintain the osmotic pressure.

(d) Hormonal reactions are generally slower than nervous reactions because:
(i) Hormones are carried in the blood but nerve impulses are carried by special neurons.
(ii) Hormones usually have a generalized action and nerve impulses are carried directly to a target organ or a cell.