Question

Human endocrine gland regulating body rhythms is

• A. Adrenal
• B. Pineal
• C. Thymus
• D. Thyroid

Answer 1

The correct option is B Pineal

A. The adrenal gland is composed of two tissues - adrenal medulla (internal) and adrenal cortex (external). The adrenal medulla secretes two hormones called adrenaline or epinephrine and noradrenaline or norepinephrine. These hormones increase alertness, pupillary dilation, piloerection, sweating, heartbeat, the strength of heart contraction and rate of respiration. The adrenal cortex secretes corticoids.

B. The pineal gland secretes a hormone called melatonin. This plays a very important role in the regulation of a 24 hour (diurnal) rhythm of the body.

C. Thymus gland secretes the peptide hormones called thymosins. It plays a major role in the differentiation of T-lymphocytes, which provide cell-mediated immunity.

D. The thyroid gland secretes tetraiodothyronine and triiodothyronine. These controls basic metabolic rate, physical growth and metabolism of proteins, fat and carbohydrate.

So, the correct answer is 'pineal'.