Question

Daily rhythms are associated with

• A. Pituitary gland
• B. Thymus
• C. Pineal gland
• D. Hypothalamus

Answer 1

Answer: (C)

Pineal gland

A. Pituitary gland is the master gland that regulates the activity of other endocrine glands and secretes many hormones like growth hormone, follicle stimulating hormone, thyroid stimulating hormone etc.

B. Thymus gland is associated with the development of immune system and present on the dorsal side of heart. It secretes thymosin hormone which plays an important role in the differentiation of T-lymphocytes.

C. Pineal gland is a small, rounded and reddish brown gland present at the dorsal side of forebrain. This gland secretes melatonin and serotonin hormones. Melatonin is derived from amino acid tryptophan and secreted from pineal gland. It regulates the 24 hour rhythm of our body like sleep-wake cycle, temperature etc. and also affects metabolism and pigmentation.

D. Hypothalamus is present in the forebrain. This gland secretes hormones that regulate the synthesis and secretion of hormones of pituitary gland.

Hence, daily rhythms are associated with pineal gland.

So, the correct answer is 'Pineal gland'.