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The primary productivity in an… (Class 12 Biology 2023, Q7)

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BiologyCBSE Class 12 · Board exam 2023, set 57/5/1 · 1 mark · MCQ

CBSE Class 12 Biology 2023: question 7

Set in the CBSE Class 12 board exam of 2023, paper 57/5/1, section A, question 7, for 1 mark. Try it first; the hints and our step-by-step solution are below.

Q7 · 1 mark · MCQEcosystem

The primary productivity in an ecosystem is expressed as :

  1. (A)
  2. (B)
  3. (C)
  4. (D)

Source: official question paper from cbse.gov.in (PDF). See it in the full 2023 board paper, set 57/5/1.

Hints

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

Hint 1

Productivity is a rate, so it needs both per unit area and per unit time.

Hint 2

Look for an option with negative powers on both area and time.

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. Primary productivity is the biomass produced per unit area over a time period. It is expressed in (weight) or (energy).

    ½ mark

  2. The board keys option (A), , the weight unit given in NCERT.

    ½ mark

Answer: (A)

Where the marks are

  • Chooses (1 mark)

Revise the chapter

Practise this chapterBoard-style questions from Ecosystem, one at a time, marked against the answer key and marking points.Back to the full paper2023 board paper, set 57/5/1: 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.