Question

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

Assertion: In living organisms, respiratory substrates are often more than one.

Reason: Pure proteins or fats are never used as respiratory substrates.

• A. If both assertion and reason are false.
• B. If both assertion and reason are true and the reason is the correct explanation of the assertion.
• C. If both assertion and reason are true but the reason is not the correct explanation of the assertion.
• D. If assertion is true but the reason is false.

Answer 1

The correct option is C If both assertion and reason are true but the reason is not the correct explanation of the assertion.

Assertion-Reason relation

Respiratory substrate are organic substance that are oxidised at the time of respiration.

There are different types of respiratory substrates available like carbohydrates, fats, proteins, etc.

Hence, in living organisms, respiratory substrates are often more than one. Therefore, assertion is correct.

Assertion-Reason relation

Pure fats or proteins cannot be directly used as substrates, they can enter as intermediary substrates of glycolysis and the Krebs’ Cycle.

They can enter as intermediary substrates of glycolysis and the Krebs’ cycle by undergoing a series of chemical reactions. Due to these reasons, pure proteins and fats are not used as respiratory substrates.

Hence, reason is true but it is not the correct explanation of the assertion.

Final answer

(B) If both assertion and reason are true but the reason is not the correct explanation of the assertion.