The gland X which is located just below the brain in the human head secretes a chemical substance Y which controls the development of bones and muscles in the body of a person. Secretion of too little of substance Y as well as the secretion of too much of substance Y by the gland X lead to abnormal development of the body of a person.
(a) Name the gland X.
(b) What is the chemical substance Y?
(c) What happens if too little of substance Y is secreted?
(d) What happens if too much of substance Y is secreted?
(e) Name the system of glands in the human body of which gland X is a part.

Answer

(a) Pituitary gland (b) Human growth hormone (c) The person remains very short and becomes a dwarf (d) The person grows very rall and becomes a giant (e) Endocrine system