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 leads 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.

(a) In above question, the gland X is pituitary gland.

(b) The chemical substance Y is Human growth hormone.


(c) If too little of substance Y is secreted then the person becomes a dwarf (very short) because growth hormone is responsible for growth and development in humans.


(d) If too little of substance Y is secreted then the person becomes a giant (very tall) because growth hormone is responsible for growth and development in humans.


(e) Gland X (pituitary gland) is a part of the endocrine system.


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