Biology : XII-CH14 – Ecosystem – Assertion and Reason

Read the assertion and reason carefully to mark the correct option.

10 Random question from this chapter are displayed, you can take the quiz multiple times to cover all questions

1 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: Forest, grassland and desert are examples of terrestrial ecosystem.

Reason: Ecosystem is a functional unit of nature.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

2 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: Phosphorus cycle is sedimentary cycle.

Reason: Reservoir of phosphorus located in earth’s crust.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

3 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: In primary succession on rocks pioneer species are usually lichens.

Reason: They are able to secret acids to dissolve rocks helping in weathering and soil formation.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

4 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: Ecosystem is an open system.

Reason: Ecosystem exchange mass as well as energy from surrounding.

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

Both (A) and (R) are true and (R) is correct explanation of the assertion

5 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: Despite occupying about 70% of surface, the productivity of oceans is only 55 million to us.

Reason: Light and minerals are limiting factor for productivity of ocean.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

6 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: Amount of nutrient present in the soil at any given time, in a given ecosystem is referred as the standing state.

Reason: Each trophic level has a certain mass of living material at particular time is known as the standing crop.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

7 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: Secondary productivity is defined as the rate of formation of new organic matter by producers.

Reason: Secondary productivity = GPP – R.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

8 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: Length of food chain is limited.

Reason: Energy hypothesis explain it because of inefficiency of energy transfer along the chain.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

9 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: Vertical distribution of different species occupying different levels is called stratification.

Reason: Tree occupy top vertical strata of forest.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

10 / 10

Read the assertion and reason carefully to mark the correct option out of the options given below:

Assertion: In terrestrial ecosystem, a large amount of energy passes through detritus food chain.

Reason: Energy for detritus food chain comes from sun.

Both (A) and (R) are true and (R) is correct explanation of the assertion

Both (A) and (R) are true and (R) is not correct explanation of the assertion

(A) is true but (R) is false

Both (A) and (R) are false

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