Question

A hormone secreted by the posterior lobe of the pituitary is concerned with
A) Contraction of uterine muscles
B) Secondary sexual characters
C) Stimulation of thyroids
D) Metabolism of carbohydrates

Answer 1

Hint: The pituitary gland is the master gland of the body which is situated in the brain, and it has two lobes which are anterior and posterior pituitary, where this gland is under the control of the hypothalamus, where this posterior pituitary directly don’t produce any hormones where hypothalamus produce two hormones, which are stored and secreted by the posterior lobe of the pituitary gland.

Complete answer:
The two hormones secreted by the posterior lobe of the pituitary gland are Oxytocin and vasopressin or antidiuretic hormone.
Both of these hormones are neuropeptides, and they have major roles in the body.
Oxytocin Is the neuropeptide hormone secreted by the posterior lobe of the pituitary during the third trimester of the pregnancy, where it contracts the uterine walls and helps in giving birth to the baby, it helps in labor.
And this hormone is useful for the production of milk in lactating mammals, and this is mainly produced or stimulated by the suckling of the breast by a child during feeding of milk.
Another neuropeptide hormone which is released by the posterior pituitary is vasopressin, where the main function of this hormone is to maintain the tonicity of the body fluids, where it is released in hypertonic conditions, such as high urine concentration, where it causes the reabsorption of water from the kidneys and it causes the constriction of arterioles and raises the arterial blood pressure, and this hormone also play role in sexual and social behavior.

So, the correct option is A.

Note: Oxytocin and vasopressin are the hormones secreted by the posterior pituitary where oxytocin plays important role in childbirth by uterine contraction and also initiates milk in lactating mother while vasopressin is released to maintain the tonicity of the body fluids.