Question

Assertion (A): The regulation of pH is essential for survival of mammalian cells.
Reason (R): Animal cell cultures mostly make use of Bicarbonate – carbon dioxide buffering system to maintain pH.

• A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
• B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false.
• D. Assertion (A) is false, but Reason (R) is true.

Hint:

Be clear about different types of buffer systems used, and understand the link between pH levels and various biological processes.

Answer 1

The Correct Option is B

Assertion (A): Maintaining a specific range of pH is essential for mammalian cells because their enzymes and other cellular processes operate efficiently only within this specific range, and a fluctuation in pH could lead to cell damage. Reason (R): The Bicarbonate–carbon dioxide buffering system is commonly used in cell cultures to maintain a stable pH by reacting with acids or bases in the medium. However, this is not the only way in which the pH is controlled in a cell, where cellular mechanisms also play a part in pH regulation. Explanation: Here, both the Assertion and the Reason are true, but the reason does not fully explain why pH regulation is essential for cell survival. Hence (B) is the right choice.