Reaching the Age of Adolescence - Exemplar Solutions 3
CBSE Class 8 Science
NCERT Exemplar Solutions
CHAPTER 10
Reaching the age of Adolescence
NCERT Exemplar Solutions
CHAPTER 10
Reaching the age of Adolescence
SHORT ANSWER QUESTIONS
12. Match the hormones given in Column A with their deficiency disease given in Column B.
Ans: (a) - (iii) ; (b) - (iv) ; (c) - (ii) ; (d) - (i)
Explanation: A person may suffer from goitre (a disease of the thyroid gland) when the thyroid gland does not produce the hormone thyroxine. Pituitary glands secrete growth hormones necessary for the growth of the body. A person may suffer from diabetes when the pancreas does not produce insulin in sufficient quantities. Adrenal glands secrete hormones which help to maintain the correct salt balance in the blood.
13. Lila always eats only dal and rice in every meal. She often falls ill and has become prone to diseases. Can you suggest changes in her diet which can make her healthy and free from disease?
Ans: Lila’s diet is not a balanced diet because her meal does not contain adequate nutritional requirements. She takes only proteins (dal) and carbohydrates (rice) in every meal. She requires vitamins and minerals in her meal to protect her from various diseases. She should also include fruits and vegetables in her meal.
14. Mention any two features each that are seen in boys and girls each to distinguish them from each other at puberty.
Ans: The boys can be distinguished from the girls at puberty with the help of secondary sexual characters.
Two features seen in boys at puberty are:
(i) Growth of facial hairs (moustaches and beards)
(ii) The protruding part of the throat called Adam's apple due to which their voice becomes deep/hoarse.
Two features seen in girls at puberty are:
(i) Development of mammary glands (milk-secreting glands)
(ii) Region below the waist becomes wider.
15. We should avoid taking medicines/drugs unless prescribed by a doctor. Give reasons.
Ans: Several medicines have adverse side effects and have specific dosage levels which, if not followed, may harm the body. Drugs can be addictive too and can ruin our health and happiness. Hence, medicines/drugs should be avoided unless prescribed by a doctor.
16. A few of Paheli’s classmates eat potato chips and burgers regularly during the recess at school. Are they healthy eating habits? Give reasons.
Ans: Potato chips and burgers do not possess adequate nutritional value. At the age of adolescence, consumption of balanced diet containing adequate proportion of nutrients like protein, carbohydrates, fats, vitamins and minerals is required to stay healthy and free from disease. Therefore, an adolescent person should take adequate amount of nutrients in his/her diet.
17. Read the statements given below and fill up the blanks with the correct words listed in the box.
deep, ductless, nutrients, thyroxine
(a) The meal that includes all ____ is a balanced diet.
(b) Insufficient production of ____ in the tadpoles leads to their incomplete development.
(c) Endocrine glands are also called _____ glands.
(d) After attaining puberty boys develop a____ voice.
Ans: (a) nutrients, (b) thyroxine, (c) ductless, (d) high-pitched (deep)
18. Fill the blank circles in figure 10.1 and identify the sex of child A and B.
Ans: Child A is female child. Child B is male child.