Skip to content

On the basis of the… (Class 10 Science 2025, Q29)

questionbuddy.in/q/cbse-10-science-2025-31-3-1-q29-basis-characteristics-processes-brackets-differentiate

ScienceCBSE Class 10 · Board exam 2025, set 31/3/1 · 3 marks · Short answer

CBSE Class 10 Science 2025: question 29

Set in the CBSE Class 10 board exam of 2025, paper 31/3/1, section C, question 29, for 3 marks. Try it first; the hints and our step-by-step solution are below.

Q29 · 3 marks · Short answerLife Processes

On the basis of the characteristics of the processes given in the brackets in each case, differentiate between the following:

  1. (a)

    Products of breakdown of pyruvate in aerobic and anaerobic respiration in human beings (product(s) of the processes)

    1 mark
  2. (b)

    Respiration and photosynthesis in plants (gas released)

    1 mark
  3. (c)

    Respiration in terrestrial animals and fishes (organs involved)

    1 mark

Source: official question paper from cbse.gov.in (PDF). See it in the full 2025 board paper, set 31/3/1.

Hints

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

Hint 1

What causes muscle cramps when oxygen is short?

Hint 2

Fish take dissolved oxygen from water through special organs.

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) Aerobic respiration: pyruvate is broken down in mitochondria into carbon dioxide and water (with much energy).

    ½ mark

  2. (a) Anaerobic respiration in human muscles: pyruvate is converted into lactic acid.

    ½ mark

  3. (b) Respiration in plants releases carbon dioxide.

    ½ mark

  4. (b) Photosynthesis releases oxygen.

    ½ mark

  5. (c) Terrestrial animals breathe through lungs (or skin/tracheae).

    ½ mark

  6. (c) Fishes use gills to take oxygen dissolved in water.

    ½ mark

Answer: (a) CO₂ + water vs lactic acid; (b) CO₂ vs O₂; (c) lungs vs gills

Where the marks are

  • CO₂ and water in aerobic (½ mark); lactic acid in anaerobic (½ mark)
  • CO₂ in respiration (½ mark); O₂ in photosynthesis (½ mark)
  • Lungs in terrestrial animals (½ mark); gills in fishes (½ mark)

Revise the chapter

  • Chapter: Life Processes (notes, formulas, where marks are lost and every past question)
Practise this chapterBoard-style questions from Life Processes, one at a time, marked against the answer key and marking points.Back to the full paper2025 board paper, set 31/3/1: 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.