Question

The hormone which is antagonist to the insulin is –
a) Thyroxine
b) Glucagon
c) Calcitonin
d) None of above

Answer 1

Insulin hormone is a protein-based hormone which is produced by the pancreatic cells, mostly islets. It is also the main anabolic hormone of the body which regulates the metabolism of fats by absorbing the glucose from other tissues and organs like- liver, blood and skeletal muscle cells. The function includes the maintenance of blood glucose levels in the body.

Complete answer:
b) Glucagon- insulin hormone is an antagonist to glucagon because it reacts opposite to the function of insulin. Insulin role is to maintain the glucose level in the blood stream whereas glucagon hormone is known for raising the concentration of glucose in blood.
So, option b is the correct answer.
a) Thyroxine- thyroxine hormone is secreted from the thyroid gland into blood and plays a role in body functioning such as- digestion, heart regulation, brain development and bone maintenance. It is being secreted in two forms- T$3$ and T$4$.
option A is incorrect.
c) Calcitonin- calcitonin hormone is also secreted by thyroid and in animals like-mammals. It has the antagonist effect of the hormone parathyroid, not the hormone insulin.
Option C is not the correct answer.
d) None of the above- this option is not applicable because one of the above options is correct.
Option D is not the correct answer.

Note:
As we discussed, both the hormones insulin and glucagon are being secreted by alpha and beta cells of islets of Langerhans cells from pancreas. When body blood sugar level is too low then, glucagon is being released by the cells to maintain the level of glucose, similarly when it is too high insulin comes into action to balance the glucose level.