1. Which life stage has Ravi entered?
2. What do you call the sudden increase in height seen in Ravi?
3. Mention the approximate age range for this stage in humans.

Answers:

(i) Ravi has entered the stage of adolescence, the period between childhood and adulthood.

(ii) The sudden increase in height is called a growth spurt.

(iii) Adolescence usually begins around 11 years and continues up to about 18–19 years of age.

1. What is meant by puberty?
2. Why has Meera reached puberty earlier than her brother?
3. Name one physical change that indicates Meera has reached puberty.

Answers:

(i) Puberty is the stage during adolescence when the reproductive organs mature and the body becomes capable of reproduction.

(ii) Generally, girls attain puberty earlier than boys, so Meera (a girl) has reached puberty before her younger brother.

(iii) The beginning of menstruation is one physical change indicating that Meera has reached puberty. (Change in body shape is another.)

1. Give one reason why all children do not reach puberty at exactly the same age.
2. Who usually attains puberty first – boys or girls?
3. Which two changes mentioned in the case show that boys are nearing puberty?

Answers:

(i) The age of puberty varies due to factors like nutrition, health, heredity and environment.

(ii) Girls usually attain puberty earlier than boys.

(iii) Development of a deeper voice and appearance of a moustache show boys are nearing puberty.

1. What main change in body shape is seen in Ritu?
2. What main change in body shape is seen in Sameer?
3. Why are their body shapes changing in different ways?

Answers:

(i) Ritu’s hips have broadened and her body has become more rounded.

(ii) Sameer’s shoulders have broadened and his muscles have developed.

(iii) Their body shapes change differently because female and male bodies develop in different ways at puberty to prepare them for their respective roles in reproduction.

1. Which organ is mainly responsible for the change in Amit’s voice?
2. What do you call the bulge formed by this organ in the neck of boys?
3. Why does Amit’s voice crack during this stage?

Answers:

(i) The larynx or voice box is mainly responsible for the change in Amit’s voice.

(ii) The bulge is called the Adam’s apple.

(iii) At puberty the larynx in boys grows quickly and the vocal cords become longer and thicker. Until the muscles adjust to this growth, the voice may crack or break for some time.

1. Which glands have become overactive in Sana’s skin?
2. What skin problem is she facing due to these glands?
3. Mention any one hygienic habit Sana should follow to reduce such skin problems.

Answers:

(i) The sweat glands and sebaceous (oil) glands have become overactive.

(ii) She is facing acne or pimples due to extra oil and blocked pores.

(iii) She should bathe daily, keep her face clean using mild soap, and wear clean clothes to maintain good personal hygiene.

1. Name the gland the doctor is talking about.
2. Which hormone secreted by this gland controls overall body growth?
3. How does this gland help in starting puberty in boys and girls?

Answers:

(i) The gland is the pituitary gland.

(ii) The growth hormone secreted by the pituitary controls overall body growth.

(iii) It secretes hormones that stimulate testes to produce testosterone in boys and ovaries to produce oestrogen in girls, thus starting puberty.

1. Which hormone helped Rohit respond quickly?
2. Name the gland that secretes this hormone.
3. What immediate changes did this hormone cause in Rohit’s body?

Answers:

(i) The hormone is adrenaline.

(ii) It is secreted by the adrenal glands present above the kidneys.

(iii) Adrenaline increased his heart rate and breathing rate and supplied more energy to his muscles, preparing him for “fight or flight”.

1. Name the endocrine gland which produces insulin.
2. What is the main function of insulin?
3. What disease is caused by lack of insulin?

Answers:

(i) Insulin is produced by the pancreas.

(ii) Insulin controls the blood sugar (glucose) level in the body.

(iii) Lack of insulin causes the disease called diabetes.

1. What is the first menstrual flow called?
2. What does the beginning of menstruation indicate about Priya’s body?
3. How frequently does menstruation usually occur?

Answers:

(i) The first menstrual flow is called menarche.

(ii) It indicates that Priya has entered the reproductive phase and her reproductive organs have matured.

(iii) Menstruation usually occurs once in about 28–30 days.

1. Why is it important to use clean sanitary pads during menstruation?
2. Mention any one health problem that may occur due to poor menstrual hygiene.
3. Should girls avoid school during menstruation? Give a reason.

Answers:

(i) Clean sanitary pads are important to prevent the growth of germs and avoid infections of the reproductive tract.

(ii) Poor menstrual hygiene may cause infections in the genital area and bad odour.

(iii) No, girls should not avoid school during menstruation because it is a natural process and can be managed with proper hygiene; missing school can disturb studies.

1. Name the stage when menstruation stops permanently.
2. What does this stage indicate about the woman’s reproductive phase?
3. At what age does this stage usually occur in women?

Answers:

(i) The stage is called menopause.

(ii) It indicates that the woman’s reproductive phase has ended and she can no longer reproduce.

(iii) Menopause usually occurs between 45–50 years of age.

1. Which chromosomes does a mother have in her body cells?
2. Which chromosomes does a father have in his body cells?
3. Why is it wrong to blame the mother for the birth of a girl child?

Answers:

(i) The mother has two X chromosomes, i.e., XX.

(ii) The father has one X and one Y chromosome, i.e., XY.

(iii) The mother always contributes an X chromosome in the egg. The father’s sperm may carry X or Y. If an X-bearing sperm fertilises the egg, the child is a girl (XX). So the father’s sperm determines the sex, not the mother.

1. What will be the sex of the child with the combination XX?
2. What will be the sex of the child with the combination XY?
3. What important value does teaching this concept promote in society?

Answers:

(i) The combination XX produces a girl child.

(ii) The combination XY produces a boy child.

(iii) It promotes the value of gender equality and helps to remove discrimination against girls by showing that the birth of a boy or girl is a natural, scientific process.

1. Which tiffin is better for adolescents? Why?
2. Name any two nutrients abundantly present in Tiffin A.
3. Why should Tiffin B style food be avoided as a daily meal?

Answers:

(i) Tiffin A is better because it is closer to a balanced diet, containing cereals, pulses, vegetables and fruits needed for healthy growth.

(ii) Tiffin A is rich in proteins (dal) and vitamins and minerals (vegetables and fruits).

(iii) Tiffin B has mainly fats and sugars and very few useful nutrients. Eating such junk food regularly can cause obesity and poor health.

1. Why did many students suffer from skin infections and bad odour?
2. Which glands are mainly responsible for sweat and oil on the skin?
3. Mention any two hygiene practices that can prevent such problems.

Answers:

(i) Due to lack of personal hygiene, sweat and oil remained on the skin allowing germs to grow, causing infections and bad odour.

(ii) Sweat glands and sebaceous (oil) glands are responsible.

(iii) (a) Taking a daily bath with soap and clean water. (b) Wearing clean, dry clothes and undergarments.

1. What type of changes is Arjun mainly experiencing?
2. Why are such changes common in adolescence?
3. Suggest any one healthy way by which Arjun can manage these feelings.

Answers:

(i) Arjun is mainly experiencing emotional changes and mood swings.

(ii) These changes are common because hormones affect our emotions and adolescents face new responsibilities and expectations.

(iii) Arjun can talk openly with a trusted elder or counsellor, share his feelings, and practise self-control instead of reacting in anger.

1. What kind of pressure were Kabir’s friends putting on him?
2. Mention any two harmful effects of smoking.
3. What positive quality did Kabir show by refusing?

Answers:

(i) They were putting peer pressure on Kabir to adopt a harmful habit.

(ii) Smoking can (a) damage the lungs and cause cough and breathing problems, and (b) lead to addiction and diseases like lung cancer.

(iii) Kabir showed courage, self-control and awareness by saying “No” to smoking.

1. How does Neha’s routine support her physical health?
2. How does outdoor play help her mental health?
3. Which one habit of Neha do you think is most important for adolescents? Give a reason.

Answers:

(i) Regular meals with fruits and vegetables, physical activity and proper sleep help her grow well, stay fit and avoid illness.

(ii) Outdoor play reduces stress, improves mood and increases concentration, supporting good mental health.

(iii) Any one habit can be chosen, e.g. balanced diet or regular exercise or good hygiene, because each is essential for healthy growth during adolescence.