Students can refer to these Reaching the Age of Adolescence MCQ Questions for Class 8 with Answers and assess their preparation level. These MCQ Questions with answers pave for a fast revision of the Chapter thereby helping you to reinforce subject knowledge. MCQ Questions for class 8 Science with Answers are prepared as per the newest Exam Pattern. Students can solve Class 8 MCQ Questions and assess their preparation level.

Students can practice the Class 8 Science MCQ Questions of Reaching the Age of Adolescence with Answers is available here. Revise all the concepts easily by taking help from the MCQ Questions for Class 8 Science with Answers are prepared based on the latest exam pattern and syllabus. MCQ Questions are often of maximum help as you’ll remember all the concepts. Let us look at the Class 8 MCQ Question of Reaching the Age of Adolescence with answers.

Practice Class 8 Science MCQ Questions chapter-wise

1. Adolescence is the period of

(a) 5 to 10 years
(b) 13 to 19 years
(c) 22 to 28 years
(d) 30 to 40 years

2. When a sperm having X-chromosome fuses with the ovum, the child born will be

(a) male
(b) female
(c) male as well as female twin
(d) it depends on the chance of fusion

3. How many pairs of Chromosomes are found in nuclei of their cells?

(a) 22 pairs
(b) 23 pairs
(c) 24 pairs
(d) 25 pairs

4. Children gain height during

(a) adolescence
(b) endocrine
(c) balanced food
(d) menarche

5. Testes secrete

(a) thyroxin
(b) estrogen
(c) testosterone
(d) iodine

6. Adam’s apple is

(a) enlarged larynx
(b) mammary glands
(c) apple of adam
(d) red-apple

7. The chemical substances which are secreted from endocrine glands are called

(a) puberty
(b) hormones
(c) estrogen
(d) adolescence

8. Out of these which one determines the sex of the baby?

(a) Hormones
(b) Chloroplast
(c) Chromosomes
(d) Pituitary gland

9. What is the stoppage of menstruation called?

(a) Menarche
(b) Menopause
(c) Gametes
(d) Insulin

10. Which hormone is secreted by adrenal glands?

(a) Adrenalin
(b) Insulin
(c) Testosterone
(d) Estrogen

11. Reproduction age in women starts when their

(a) menstruation starts
(b) breasts start developing
(c) body weight increases
(d) height increases

12. Which is male gonads?

(a) Hair
(b) Chest
(c) Moustache
(d) Testis

13. In males, the sex chromosome consists

(a) one X and one Y
(b) both X and X
(c) both Y and Y
(d) one M and one X

14. Production of thyroxin requires

(a) sodium
(b) magnesium
(c) iodine
(d) bromine

15. The human body undergoes several changes during adolescence. These changes mark the onset of

(a) Puberty
(b) Prematurity
(c) Post adolescence
(d) aging

16. Larynx is also called

(a) Voicebox
(b) Soundbox
(c) Black box
(d) Both A and B 

17. Acne and pimples on the face are due to the secretion of

(a) bile from liver
(b) Oil glands during puberty
(c) Enzymes in the digestive tract
(d) Tear from tear glands

18. Testosterone is a hormone found in humans ___

(a) Children
(b) males and females
(c) Females only
(d) Males only

19.  Statement 1: Sweat glands, salivary glands, and oil glands do not release their secretions directly into the blood. 

Statement 2: These glands do not have ducts.

(a) Both the statements are correct.
(b) Both the statements are correct.
(c) Both the statements are incorrect.
(d) Only statement 1 is correct.

20. The information given below refers to which of the following hormone- (i) Glands secreting the hormone are located on top of the kidneys. (ii) Converts glycogen into glucose. (iii) Increases blood pressure.

(a) Testosterone
(b) Insulin
(c) Adrenaline
(d) Progesterone

21. Which of the following viruses causes AIDS?

(a) H1N1 virus
(b) Zika virus
(c) HIV
(d) Rhinovirus

22. Which of the following is the change seen in girls during puberty?

(a) Broader shoulders
(b) Cracking of voice
(c) Breast development
(d) Growth of facial hair

23. The pituitary gland is located below the ______.

(a) Thalamus
(b) medulla oblongata
(c) vas deferens
(d) hypothalamus

24. Which of the following can spread AIDS?

(a) Eating food with an infected person
(b) Hugging an infected person
(c) Transfusion of infected blood
(d) Mosquito bites

25. Deficiency of iodine in our diet leads to a condition called:

(a) Diabetes insipidus
(b) Goitre
(c) Gigantism
(d)  Infertility

Answer:

1. Answer: (b) 13 to 19 years

Explanation: Adolescence is the transition period from childhood to adulthood. The adolescent age group is from 13 to 19 years. Thus, a person belonging to this age group or teens is said to be a teenager or an adolescent.

2. Answer: (b) female

Explanation: The process of fusion of a sperm with an ovum is called fertilization. During fertilization, a sperm comes in contact with the zona pellucida layer of the ovum and induces changes in the membrane which blocks the entry of additional sperms. This also induces the formation of the haploid secondary oocyte, by meiotic division, which fuses with sperm to form a zygote. At this stage the sex of the baby is determined. Males have XY chromosomes so sperms who have haploid no. of chromosomes carry either X or Y. While females have XX chromosomes, so all ovum will carry the X chromosome. So when a sperm containing an X chromosome fertilizes an ovum, a zygote with XX chromosomes is formed. Thus a female child is born.

3. Answer: (b) 23 pairs

Explanation: A chromosome is an organized package of DNA found in the nucleus of the cell. Different organisms have different numbers of chromosomes. Humans have 23 pairs of chromosomes - 22 pairs of numbered chromosomes, called autosomes, and one pair of sex chromosomes, X and Y.

4. Answer: (a) adolescence

Explanation: As we know children gain height during adolescence. It is also known as 'teenagers'. Changes occur in this period.

5. Answer: (c) testosterone

Explanation: The main hormone secreted by the testes is testosterone, an androgenic hormone. Testosterone is secreted by cells that lie between the seminiferous tubules, known as the Leydig cells.

6. Answer: (a) enlarged larynx

Explanation: When the larynx grows larger during puberty, it sticks out at the front of the throat. This is what's called Adam's apple. Everyone's larynx grows during puberty, but a girl's larynx doesn't grow as much as a boy does. That's why boys have Adam's apples.

7. Answer: (b) hormones

Explanation: Endocrine glands, situated at various sites around the body, and in specialized areas of the brain. The cells in these glands secrete specific chemicals called hormones. Hormones circulate around the body via the bloodstream and modulate cellular or organ functions by binding with receptors in the target cells.

8. Answer: (c) Chromosomes

Explanation: The father is responsible for determining the sex of the child. The mother has two X chromosomes and donates one X chromosome in the gamete. The father has X and Y chromosomes and so the gamete can contain X or Y. The male gamete which fuses with the egg is responsible for the sex of the baby.

9. Answer: (b) Menopause

Explanation: Menarche is the first menstrual cycle in female humans. Menopause is the end of the menstrual cycle.

10. Answer: (a) Adrenalin

Explanation: The main hormones secreted by the adrenal medulla include epinephrine (adrenaline) and norepinephrine (noradrenaline), which have similar functions.

11. Answer: (a) menstruation starts

Explanation: In females, the reproductive phase of life begins at puberty (10 to 12 years of age) and generally lasts till the age of approximately 45 to 50 years.

12. Answer: (d) Testis

Explanation: In males, they are the testes, or testicles, the male sex glands that are part of the male reproductive system. They are located behind the penis in a pouch of skin called the scrotum. The female gonads, the ovaries, are a pair of reproductive glands.

13. Answer: (a) one X and one Y

Explanation: biologically male individuals have one X and one Y chromosome (XY) while those who are biologically female have two X chromosomes. However, there are exceptions to this rule. The sex chromosomes determine the sex of offspring.

14. Answer: (c) iodine

Explanation: Micronutrients, mostly iodine, and selenium are required for thyroid hormone synthesis and function. Iodine is an essential component of thyroid hormones and its deficiency is considered as the most common cause of preventable brain damage in the world.

15. Answer: (a) Puberty

Explanation: Adolscence is period between childhood and adulthood when the body of the child undergoes certain changes to prepare the body to be able to reproduce. The start of these changes that lead to reproductive maturity are known as puberty.

16. Answer: (d) Both A and B

Explanation: In males, the larynx increases in size during the adolescence period because of changes due to puberty. It is also called 'Adam's apple'. From the pharynx, air enters the larynx through an opening called the glottis. Along the sides of the glottis are two folds of elastic tissue called vocal cords. These are responsible for producing sound. Hence larynx is also called the voice box or the soundbox. 

17. Answer: (b) Oil glands during puberty

Explanation: Acne and pimple are manifestations on the skin due to clogging of the overactive oil glands (sebaceous glands) on the face. It is a sign of adolescence.
The correct answer is 'oil glands during puberty.

18. Answer: (d) Males only

Explanation: Testosterone is a hormone found in humans, as well as in other animals. In men, the testicles primarily make testosterone

19. Answer: (d) Only statement 1 is correct.

Explanation: Endocrine glands release their secretions directly into the blood as they are ductless glands, whereas the exocrine glands like salivary glands have ducts and do not release their secretion into the blood directly.

20. Answer: (c) Adrenaline

Explanation: Adrenaline is secreted by the adrenal glands which are located on top of the kidneys. This hormone prepares the body to fight or run away during an emergency situation. Its effects involve an increase in heart rate, blood pressure, breathing rate, blood glucose level, etc.

21. Answer: (c) HIV

Explanation: AIDS is caused by the Human Immunodeficiency Virus (HIV) virus. HIV passes from an infected person to a normal person through sexual contact, sharing syringes, breastfeeding, etc.

22. Answer: (c) Breast development

Explanation: One of the major changes in girls during puberty is breast development. Also, in girls, the region below the waist becomes wider during puberty while in boys the chest becomes wider and shoulders become broad.

23. Answer: (d) hypothalamus

Explanation: The pituitary gland is a pea-sized gland located just below the hypothalamus which is connected to the pituitary via a bundle of nerve fibers. It is known as the master gland of the endocrine system as it produces all the critical hormones which regulates the secretions of all other endocrine glands.

24. Answer: (c) Transfusion of infected blood

Explanation: AIDS is caused by the HIV virus. It can spread through various means like

(i) Sexual contact with an infected person. 

(ii) Transfusion of contaminated blood.

(iii) From a pregnant mother to her child during birth or breastfeeding. 

It does not spread by: 

(i) Touching, kissing and socializing with the infected person. 

(ii) Eating meals with an infected person

(iii) Mosquito bites

25. Answer: (b) Goitre

Explanation: Iodine is essential for the production of thyroxine. In an attempt to produce more thyroxine, the gland enlarges. This condition is called goiter.

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