Skip to content

Answer the following. (Science 2025 31/6/1 Q35a)

questionbuddy.in/q/cbse-10-science-2025-31-6-1-q35a

ScienceCBSE Class 10 · Board exam 2025, set 31/6/1 · 5 marks · Long answer

CBSE Class 10 Science 2025: question 35(a)

Set in the CBSE Class 10 board exam of 2025, paper 31/6/1, section D, question 35(a), for 5 marks. Try it first; the hints and our step-by-step solution are below.

Q35(a) · 5 marks · Long answerHow do Organisms Reproduce?

Answer the following.

  1. (a)

    Define Puberty. List any two changes seen in boys at the time of puberty.

    0 marks
  2. (b)

    Why are testes in human males located outside the abdominal cavity in scrotum ?

    0 marks
  3. (c)

    List any three techniques of contraception used by humans. Which one of these is not meant for males ?

    0 marks

Source: official question paper from cbse.gov.in (PDF). See it in the full 2025 board paper, set 31/6/1.

Hints

Open one hint at a time and try again before the next.

Hint 1

Puberty is linked to the maturing of reproductive tissues. Which visible changes appear in boys?

Hint 2

Compare the temperature needed for making sperm with normal body temperature.

Hint 3

Group the contraceptive methods as barrier, chemical, intrauterine and surgical. Which of them are used only by women?

Step-by-step solution

Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.

  1. (a) Puberty is the period of adolescence when the rate of general body growth begins to slow down and the reproductive tissues begin to mature.

    1 mark

  2. (a) Change 1 in boys: thick hair grows on the face (beard and moustache), and in the armpits and genital area.

    ½ mark

  3. (a) Change 2 in boys: the voice begins to crack (becomes deeper).

    ½ mark

  4. (b) Sperm formation needs a temperature lower than normal body temperature. The scrotum keeps the testes outside the abdominal cavity, where the temperature is about 2–3 °C lower.

    1 mark

  5. (c) Technique 1, mechanical barrier: a condom, which stops sperm from reaching the egg.

    ½ mark

  6. (c) Technique 2, chemical/hormonal method: oral pills.

    ½ mark

  7. (c) Technique 3, intrauterine device: a loop or Copper-T placed in the uterus. (Surgical methods such as vasectomy or tubectomy are also acceptable.)

    ½ mark

  8. The methods not meant for males are oral pills and the loop or Copper-T, which are used by females.

    ½ mark

Answer: (a) Puberty: growth slows and reproductive tissues mature; e.g. facial hair, cracking of voice; (b) sperm formation needs a lower temperature; (c) condom, oral pills, Copper-T; oral pills / Copper-T not meant for males.

Where the marks are

  • Definition of puberty (1 mark)
  • Any two changes in boys (½ × 2 = 1 mark)
  • Lower temperature needed for sperm formation (1 mark)
  • Any three contraceptive techniques (½ × 3 = 1½ marks)
  • Identifies oral pills or Copper-T as not meant for males (½ mark)

Revise the chapter

Practise this chapterBoard-style questions from How do Organisms Reproduce?, one at a time, marked against the answer key and marking points.Back to the full paper2025 board paper, set 31/6/1: every question, by section.

The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.