Question

This question consist of two statements, assertion and reason. While answering this question you are required to choose any one of the following five responses.

Assertion: Amaranthus and sugarcane are called as Hatch and Slack plants.

Reason: One glucose is formed by fixation of 6 $C{O}_2$ in the plants.

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

Answer 1

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

Assertion-Reason relation

$C_4$ cycle is also known as ‘Hatch and Slack’ pathway. Hatch and Slack traced the path of carbon in $C_4$ cycle, hence is the name. This pathway is seen in various monocots such as maize, sugarcane and grasses etc. and also in some dicots like Amaranthus. Hence, the assertion is correct.

Assertion-Reason relation

Because the glucose molecule has six carbon atoms, it takes six turns of the Calvin cycle to make one such molecule. One turn of Calvin cycle occurs for each carbon dioxide molecule. So, the reason is also correct.

However, the reason 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.