Question

The hormone which regulates the gene expression of the target cells is

• A. Prolactin
• B. Oxytocin
• C. Thyroxine
• D. Growth hormone

Answer 1

Answer: (C)

Thyroxine

A. Prolactin, also known as lactogenic hormone is produced by the pituitary gland. This hormone stimulates the production of milk in mammary glands during pregnancy.

B. Oxytocin is secreted from the posterior pituitary and helps in the contraction of uterus during childbirth and also stimulates release of milk from mammary glands i.e. lactation.

C. Thyroxine is secreted from thyroid gland. It stimulates the consumption of oxygen by metabolically active tissues and also increases the oxidation of glucose in tissues.

D. Growth hormone is secreted from anterior part of pituitary gland and stimulates body growth and metabolism of carbohydrates, fats and proteins.

The hormone that regulates gene expression of target cells is thyroxine because its receptors are present inside the cell. Thyroxine binds with the receptor to form a hormone-receptor complex. This complex binds to promoter region of the gene and affects transcription of the gene by either activating it or inhibiting it.

So, the correct answer is 'Thyroxine'.