Question

Assertion (A): In glycolysis, glucose breaks down to pyruvic acid without utilizing oxygen.
Reason (R): An living organism retain enzymatic machinery to partially oxidize glucose without the help of oxygen.

• A. Both (A) and (R) are correct and (R) is the correct explanation to (A)
• B. Both (A) and (R) are correct but (R) is not correct explanation for (A)
• C. (A) is correct (R) is wrong
• D. (A) is wrong (R) is correct

Hint:

Glycolysis is the only pathway of respiration common to both aerobic and anaerobic respiration.
Because it occurs in the cytoplasm, it does not require mitochondria or molecular oxygen.

Answer 1

The Correct Option is B

Step 1: Confirm the Assertion.
Glycolysis breaks one glucose into two pyruvate molecules entirely in the cytosol, and none of its ten reactions needs molecular oxygen. So A is correct.
Step 2: Confirm the Reason.
Living cells do carry enzymes that can partially oxidise glucose without oxygen, which is also a true statement about cell biochemistry in general.
Step 3: Check the link between them.
R is a broad statement about organisms in general keeping such machinery, while A is a specific description of the glycolysis pathway itself. R supports the idea in a general sense but does not spell out the actual mechanism that makes glycolysis oxygen-independent.
Final answer: Option 2, Both A and R are true, but R does not directly explain A.