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List the events in proper… (Class 10 Science 2023, Q23a)

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ScienceCBSE Class 10 · Board exam 2023, set 31/5/1 · 2 marks · Very short answer

CBSE Class 10 Science 2023: question 23(a)

Set in the CBSE Class 10 board exam of 2023, paper 31/5/1, section B, question 23(a), for 2 marks. Try it first; the hints and our step-by-step solution are below.

Q23(a) · 2 marks · Very short answerLife Processes

List the events in proper sequence that take place during the process of photosynthesis.

Source: official question paper from cbse.gov.in (PDF). See it in the full 2023 board paper, set 31/5/1.

Hints

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

Hint 1

Photosynthesis happens in three steps. Which pigment must act first?

Hint 2

After the energy is trapped, what happens to water, and where does the energy go?

Hint 3

The last step involves carbon dioxide. What does it become?

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. (i) Chlorophyll absorbs light energy.

    ½ mark

  2. (ii) The light energy is converted into chemical energy, and water molecules are split into hydrogen and oxygen.

    1 mark

  3. (iii) Carbon dioxide is reduced to carbohydrates.

    ½ mark

Answer: Absorption of light by chlorophyll → conversion of light energy to chemical energy and splitting of water → reduction of CO₂ to carbohydrates

Where the marks are

  • Absorption of light energy by chlorophyll (½ mark)
  • Conversion of light energy to chemical energy and splitting of water into hydrogen and oxygen (1 mark)
  • Reduction of CO₂ to carbohydrates (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 paper2023 board paper, set 31/5/1: 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.