Question

Assertion: Cardiac muscle can contract continuously without fatigue.

Reason: Cardiac muscle cells have a high number of mitochondria and an abundant blood supply.

Options

• Both (A) and (R) are true, and (R) is the correct explanation of (A).

• Both (A) and (R) are true, but (R) is not the correct explanation of (A).

• (A) is true, but (R) is false.

• (A) is false, but (R) is true.

Answer 1

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

Explanation:

The assumption is correct since cardiac muscles operate continuously and rhythmically throughout life without fatigue, allowing the heart to continue pounding.

The reason is true and is the correct answer because cardiac muscle cells have a high number of mitochondria that produce a steady source of energy, as well as an adequate blood supply that gives oxygen and nutrients on a continuous basis. Together, these enable the muscle to contract without fatigue.