Question

Assertion (A) : The survival of heterotrophs depends directly or indirectly on autotrophs.
Reason (R) : Heterotrophic organisms include animals and plants.
(1) Both (A) and (R) are true and (R) is the correct explanation of (A)
(2) Both (A) and (R) are true but (R) is not the correct explanation of (A)
(3) (A) is true but (R) is false
(4) (A) is false and (R) is true​

Answer 1

Assertion(A)

The survival of heterotrophs depends directly or indirectly on autotrophs.

• This statement is true.
• Because as sunlight reaches the surface leaves,they make food for themselves in the form of starch(glucose).
• Hence,they are autotrophs.
• Solar enegy is the prime and initial source of energy.
• Now plants are in turn eaten by Herbivores(cow,goat). Here the heterotrophs are directly dependent on plants(autotrophs)
• Now herbivores will in turn get eaten by top consumers(seconday consumers),eg, lion,human etc.
• Here the secondary consumers are dependent on herbivores and herbivores are dependent on plants.So,indirectly sec. consumers are also dependent on plants.
• We can say here, heterotrophs are directly/ indirectly dependent on plants.

Reason(R)

Heterotrophic organisms include animals and plants.

• This statement is false.
• Heterotrophs are those which are dependent on others for food.While,autotrophs prepare their own food.
• All plants are autotrophs except some carnivorous plants(like utricularia, pitcher plant, venus fly trap)
• Animals are heterotrophic.

$\star$ Assertion is true, Reason is false.

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Answer 2

Assertion:

The survival of heterotrophs depends directly or indirectly on autotrophs.

Reason:

Heterotrophic organisms include animals and plants.

Assertion is true but Reason is false (Option 3)

Assertion explaination:

• Autotrophs are the organisms that can produce/manufacture food by themselves. And they are not dependent on others for food.

• Some of the autotrophs are green plants and blue green algae.

• But heterotrophs depend on autotrophs for food. This is because, they can't produce their own food.

• Herbivores (heterotrophs) are directly dependent on autotrophs, whereas carnivores (also heterotrophs which feed on herbivores) indirectly depend on plants.

• Hence Assertion is True.

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Reason explanation:

• Heterotrophs just don't include plants and animals. All animals and some non-green plants are heterotrophs.

• However, they are many other kingdom of organisms which are heterotrophs (like fungi, etc)

• Hence Reason is false.

$\star$ Hope It Helps.