Worksheet solutions for chapter: Reaching the Age of Adolescence for class 8 are provided below.
(1) What is puberty?
The period in which adolescence reaches to sexual maturity and ready to reproduces the young ones, is called puberty.
(2)How voice changes in adolescents?
The change in voice of adolescence is called cracks in voice. The voice changes because of growth of voice box or the larynx. The voice boxes or larynx can be seen in boys. The growing voice box which can be seen as a protruding part of the throat is called Adam’s apple. Girls have small Adam’s apple which can not be visible from outside.
(3)What are ductless glands?
The gland which releases their secretion direct into blood stream is called ductless glands.
Eg:- Endocrine glands
(4)Write shot notes on
(i) Pituitary gland
(ii) Target site
(i) The production of these hormones is under the control of another hormone secreted from an endocrine gland called pituitary gland.
(ii) Target site is a particular body part where hormones released by the endocrine glands into blood stream reached and target site respond to hormones.
(5) Write the difference between menarche and menopause.
The differences between menarche and menopause are tabulated below:-
|It is the first flow of menstruation cycle.||It is the stoppage if the menstruation cycle.|
|It begins at the age of 10 – 12.||It stops at the age of 45 – 50 years.|
(6) List the hormones and their secretion gland.
(7) Fill in the blanks
(i) Thyroid gland produces _____ hormone.
(ii) All human have ____ pair of chromosomes.
(iii) Testosterone hormone is a a______hormone.
(i) Thyroid gland produces thyroxine hormone.
(ii) All human have 23 pair of chromosomes.
(iii) Testosterone hormone is a male hormone.
(8)Write short note on personal hygiene of adolescents.
(a) Adolescence should take bath everyday because the increased activity of the sweat glands sometimes makes the body smelly. Therefore all parts of the body should be washed and cleaned to prevent the bacterial growth.
(b) Girls should take care of personal hygiene during the flow of menstruation. They should note date of the menstrual cycle.
(9) Match the items of group A with items of group b.
Group A Group B
(i) Female chromosomes 10 – 12 years
(ii)Duct gland X
(iii) Menstruation cycle begin sweat gland
Group A Group B
(i) Female chromosomes 10 – 12 years (iii)
(ii) Duct gland X (i)
(iii) Menstruation cycle begin sweat gland (ii)
(10) What will happen if water of pond in which tadpoles are growing does not contain iodine?
The tadpoles will not become adult if water of pond in which tadpoles are growing does not contain iodine.