Question

    9.    Which of the following is not true of oxytocin?

a.
It is produced in the posterior pituitary gland.
b.
It causes the contractions of the uterus during labor.
c.
It is one of the few hormones that is regulated by a positive feedback loop.
d.
It stimulates “milk letdown” in nursing mothers.

    10.    The hypothalamus

a.
is composed of a glandular portion and a nerve portion
b.
produces ADH
c.
releases ADH
d.
is located in the sella turcica

    11.    Thyroxine

a.
has fewer iodine atoms than triiodothyronine
b.
stimulates the release of thyroid-stimulating hormone
c.
has more target cells than ADH
d.
All of the above are true of thyroxine.

    12.    Calcitonin

a.
is released by the parathyroid gland
b.
prevents hypercalcemia
c.
increases the calcium level in the blood
d.
can cause Graves disease if it is hypersecreted

Answer 1

9. Oxytocin is produced in the hypothalamus and secreted by the posterior in the bloodstream.
So, option a) It is produced in the posterior pituitary gland is not true for oxytocin.

10. Hypothalamus produces ADH (Antidiuretic hormone) and is released by the pituitary gland to act further on the kidneys to control the amount of water excreted in the urine.

So, option b) produces ADH is correct.

11. Here all the given options are correct for thyroxin hormone.

So, option d) All of the above are true for thyroxine.

12. Calcitonin acts oppositely to parathyroid hormone. It is responsible for lowering the calcium level in the blood while parathyroid hormone increases the blood calcium level.

So, option d) "increases the calcium level in the blood" is an odd one from the 4 options. Other options are correct for calcitonon.