The hormone which control the processes of burning of fats, proteins and carbohydrates, with liberation of energy in the body is:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → thyroxine
Thyroxine, produced in the thyroid gland, is an iodinated derivative of the amino acid tyrosine. It controls the rate of metabolism, that is, the burning of fats, proteins and carbohydrates with liberation of energy. Too little thyroxine (hypothyroidism) slows metabolism and causes lethargy and obesity; too much (hyperthyroidism) speeds it up.
Why the other options are incorrect
Option (2) insulin — Incorrect. A polypeptide hormone of the pancreas that keeps the blood glucose level within limits; it does not set the general rate of burning of fats and proteins.
Option (3) adrenaline — Incorrect. Adrenaline (epinephrine) is the hormone of the adrenal medulla that mediates the response to external stimuli (“fight or flight”), raising heart rate and blood glucose for a short time.
Option (4) estradiol — Incorrect. A female sex hormone (steroid) responsible for the development of secondary female characteristics and control of the menstrual cycle.
NCERT (2026-27 edition):
Hormones – “Hormones have several functions in the body. They help to maintain the balance of biological activities in the body. … Thyroxine produced in the thyroid gland is an iodinated derivative of amino acid tyrosine. Abnormally low level of thyroxine leads to hypothyroidism which is characterised by lethargyness and obesity. Increased level of thyroxine causes hyperthyroidism.”