10. Reaching the age of adolescence Class 8 science Solutions English Medium-Text Book Exercise

NCERT Solutions Class 8 science English Medium

10. Reaching the age of adolescence

Topic: Text Book Exercise

Exercise

---

1. What is the term used for secretions of endocrine glands responsible for changes taking place in the body?

Answer : The term used for secretions of endocrine glands is hormoane which is responsible for various changes taking place in the body.

2. Define adolescence.

Answer : The period of life when the body undergors changes, leading to reproductive maturity, is called adolescence.

3. What is menstruation? Explain.

Answer : When the uterus receives the egg and it is fertilized, pregnacy occurs. If fertilization does not occur, the released egg and the thickened lining of the uterus along with its blood vesssels are shed off. This causes bleeding in women which is called menstruation. 

4. List changes in the body that take place at puberty.

Answer : The onset of puberty brings about :

(i) Growth of the reproductive organs which begin to function. (ii) Hair grows at various places of the body. Breasts develop in girl and facial hair (moustache and beard)  apper in boys. 

(iii) Voice of the boys becomes hoarse as voice box enlarges during adolescence. 

5. Prepare a Table having two columns depicting names of endocrine glands and hormones secreted by them.

Answer: 

Name of endocrine glands	Hormones secreted
testes	Testosterone
Ovary	Estrigen
Adrenal	Adrenalin
Thyroid glands	Thyroxine
Pituitary	FSH or Fillicle atimulating hormonre
Pancreas	Insulin

6. What are sex hormones? Why are they named so? State their function.

Answer:

Hormones secreted by testes and ovaries are termed as sex-hormones.

  They are named so because they are secreted by the reproductive organs.

Function of sex-hormones:

  They hormones are responsible for the secondary sexual charaters of male and female.

7. Choose the correct option.

(a) Adolescents should be careful about what they eat, because

(i) proper diet develops their brains.

(ii) proper diet is needed for the rapid growth taking place in their body.

(iii) adolescents feel hungry all the time.

(iv) taste buds are well developed in teenagers.

(b) Reproductive age in women starts when their

(i) menstruation starts.

(ii) breasts start developing.

(iii) body weight increases.

(iv) height increases.

(c) The right meal for adolescents consists of

(i) chips, noodles, coke.

(ii) chapati, dal, vegetables.

(iii) rice, noodles and burger.

(iv) vegetable cutlets, chips and lemon drink.

Answer:

(a) (ii), (b) (i), (c) (ii).

8. Write notes on—

(a) Adam’s apple.

(b) Secondary sexual characters.

(c) Sex determination in the unborn baby.

Answer:

(a) Adam's apple: In human males, the larynx grows larger during puberty and can be seen as a protruding part of the throat. This protrusion is known as the Adam's apple. In boys, under the influence of sex hormones, the larynx becomes prominent, As a result, the vocal cords become longer and thicker, causing the voice to become hoarse.

Concept insight: At puberty, boys develop a larger voice box called Adam's apple.

(b) Secondary sexual characters are those features that help in distinguishing the male and the female body from each other. They are physical or behavioral characteristics that appear in humans at the time of puberty.

 

Secondary sexual characters in boys:

(i) Appearance of moustache and beard.

(ii) Appearance of chest hair.

(iii) Growth of hair in genital area and other parts of the skin.

Secondary sexual characters in girls:

(i) Increase in breast size and darkening of the skin of nipples present at the tip of the breasts.

(ii) Growth of hair in genital area and other body parts.

Concept insight: Secondary sexual characters are developed during puberty.

(c) Sex determination in an unbom baby:

The sex of a baby is determined by the type of male gamete that fuses with the female gamete.

9. word game : Use the clues to work out the words.

Across

3. Protruding voice box in boys

4. Glands without ducts

7. Endocrine gland attached to brain

8. Secretion of endocrine glands

9. pancreatic hormons

10. female hormone

Down

1. Male hormone

2. Secretes thyroxine

3. Another therm for teenage

5. Hormone reaches here through blood stream

6. Voice box

7. Term for changes at adolescence

Answer:

 

NCERT Solutions Class 8 Hindi and English Medium – Complete Study Material

NCERT Solutions Class 8 students ke liye specially CBSE latest syllabus (2026-27) ke according prepare kiye gaye hain. Yeh solutions Hindi aur English medium dono ke liye available hain, jisse har student apni language preference ke hisaab se padh sakta hai. Har chapter ke sabhi prashnon ke step-by-step answers diye gaye hain jo concept clarity aur exam preparation me madad karte hain.

Chapter-Wise Detailed Explanations

Class 8 ke liye diye gaye Chapter Wise NCERT Solutions me har question ka detailed aur easy explanation diya gaya hai. Chahe aap CBSE Board Exam Preparation kar rahe ho ya school test ke liye revise kar rahe ho, yeh solutions aapko complete understanding denge. Har answer simple language me likha gaya hai jisse students concepts ko easily grasp kar saken.

Hindi and English Medium Support

Students Hindi aur English medium dono me NCERT Book Solutions Class 8 access kar sakte hain. Yeh dual language support un students ke liye helpful hai jo apni regional language me better samajhna chahte hain. Sabhi answers CBSE Latest Syllabus 2026-27 ke anusaar update kiye gaye hain.

Important Features of NCERT Solutions

• Class 8 NCERT Solutions PDF
• CBSE Class 8 Study Material
• NCERT Book Questions and Answers
• Exam Oriented Important Questions
• Step-by-Step Detailed Solutions
• Concept Clarity and Revision Notes

Why Students Should Use NCERT Solutions?

Aaj ke competitive environment me sirf textbook padhna kaafi nahi hota. NCERT Solutions for Class 8 students ko practice aur conceptual understanding dono provide karte hain. Yeh solutions unhe exam pattern samajhne, frequently asked questions practice karne aur high score achieve karne me madad karte hain. Regular practice se students apne weak topics ko improve kar sakte hain.

Best Resource for Exam Preparation

Agar aap Class 8 CBSE Preparation ke liye ek trusted aur reliable source dhundh rahe hain, to yeh NCERT Solutions perfect choice hain. Yeh study material school exams, unit tests, half-yearly aur annual exams ke liye equally useful hai. Har chapter ke answers accurate, verified aur student-friendly format me diye gaye hain.

Isliye agar aap NCERT Solutions Class 8 Hindi and English Medium search kar rahe hain, to yahan aapko complete chapter-wise solutions milenge jo aapki academic journey ko strong aur confident banayenge.