"Reaching the Age of Adolescence" for Class 8 Science CBSE:-
Extra 30 short questions and answers from the chapter:7
1. What is adolescence?
Ans: Adolescence is the period of life between childhood and adulthood (10-19 years) when the body undergoes physical, emotional, and hormonal changes leading to puberty.
2. What is puberty?
Ans: Puberty is the stage during adolescence when the body becomes sexually mature and develops secondary sexual characteristics due to hormonal changes.
3. What are secondary sexual characteristics?
Ans: Secondary sexual characteristics are physical changes that appear during puberty, such as:
Growth of facial and body hair in boys.
Development of breasts in girls.
Deepening of voice in boys.
4. Name the hormones responsible for puberty in boys and girls.
Ans:
In boys, testosterone is responsible for puberty.
In girls, oestrogen and progesterone are responsible for puberty.
5. What is menarche?
Ans: Menarche is the first occurrence of menstruation in girls, marking the start of reproductive capability, usually between 10-15 years of age.
6. What is menopause?
Ans: Menopause is the permanent stoppage of menstruation in women, occurring around 45-50 years of age, marking the end of reproductive ability.
7. What changes occur in boys during puberty?
Ans:
Growth of facial, chest, and pubic hair.
Deepening of voice due to voice box enlargement.
Increase in muscle mass and height.
Testes start producing sperm.
8. What changes occur in girls during puberty?
Ans:
Development of breasts.
Widening of hips for childbirth.
Menstruation starts (menarche).
Growth of pubic and underarm hair.
9. What is the function of the pituitary gland?
Ans: The pituitary gland is called the master gland as it:
Controls growth and development.
Regulates the function of other endocrine glands.
Produces growth hormones and hormones that trigger puberty.
10. What are the functions of testosterone?
Ans: Testosterone, the male hormone:
Controls sperm production.
Causes voice deepening.
Leads to the growth of body and facial hair.
11. What are the functions of oestrogen?
Ans: Oestrogen, the female hormone:
Helps in the development of breasts.
Controls menstruation cycle.
Aids in the maturation of eggs in ovaries.
12. What are sex hormones?
Ans: Sex hormones are hormones that control sexual development and reproduction. Examples:
Testosterone (in males).
Oestrogen & Progesterone (in females).
13. What is the role of the thyroid gland?
Ans: The thyroid gland produces thyroxine, which controls metabolism, growth, and energy production.
14. What is the function of insulin?
Ans: Insulin is a hormone released by the pancreas, which regulates blood sugar levels.
15. What is the role of the adrenal gland?
Ans: The adrenal glands produce adrenaline, the hormone that helps in emergency situations (fight or flight response).
16. What is the menstrual cycle?
Ans: The menstrual cycle is a 28-day reproductive cycle in females where:
An egg is released from the ovary.
If not fertilized, the uterine lining sheds, leading to menstruation.
17. Why do boys experience voice change during puberty?
Ans: Boys' voices become deeper due to the growth of the voice box (larynx), making the vocal cords thicker and longer.
18. What are the functions of the male reproductive organs?
Ans:
Testes – Produce sperm and testosterone.
Penis – Transfers sperm into the female body.
Vas deferens – Carries sperm from testes to the penis.
19. What are the functions of the female reproductive organs?
Ans:
Ovaries – Produce eggs and oestrogen.
Uterus – Supports embryo development.
Fallopian tube – Carries eggs to the uterus.
20. Why is a balanced diet important during adolescence?
Ans: Adolescents need a balanced diet for:
Proper growth and development.
Strong bones and muscles.
Boosting immunity.
21. What are primary sexual characteristics?
Ans: Primary sexual characteristics are reproductive organs present from birth:
Testes and penis in boys.
Ovaries and uterus in girls.
22. What is the role of growth hormone?
Ans: Growth hormone, released by the pituitary gland, controls:
Height increase during adolescence.
Bone and muscle growth.
23. What is the difference between adolescence and puberty?
Ans:
Adolescence is the overall transition from childhood to adulthood.
Puberty is the biological process of body changes during adolescence.
24. What are the common emotional changes during adolescence?
Ans: Adolescents may experience:
Mood swings.
Increased self-awareness.
Need for independence.
25. How can adolescents maintain personal hygiene?
Ans:
Regular bathing to remove sweat and bacteria.
Wearing clean clothes.
Proper genital hygiene to prevent infections.
26. Why do teenagers have increased hunger?
Ans: Due to rapid growth and metabolism, teenagers need more energy and feel hungrier.
27. Why do boys develop more muscles than girls during puberty?
Ans: Boys produce more testosterone, which promotes muscle growth and bone strength.
28. What is the importance of physical exercise during adolescence?
Ans:
Keeps the body fit and strong.
Boosts mental health.
Improves posture and bone strength.
29. Why is reproductive health important?
Ans: Reproductive health ensures:
Proper growth of reproductive organs.
Awareness about hygiene and diseases.
30. Why should adolescents avoid drug and alcohol consumption?
Ans: Drugs and alcohol can:
Harm brain development.
Cause addiction.
Affect overall health negatively.
