Question

1. what does a buffer system do when the ph gets too high? why is this important biologically? (2 marks)

Explanation:

When pH rises too high (becomes alkaline), a buffer system releases hydrogen ions ($H^+$) from its acidic component to bind with excess hydroxide ions ($OH^-$) in the solution, reducing the pH back toward its normal range.

Biologically, this is critical because nearly all cellular processes (like enzyme function, membrane stability, and molecular interactions) are highly sensitive to pH changes. Even small shifts outside the optimal pH range can denature enzymes, disrupt metabolic pathways, and lead to cell damage or death. Buffers maintain the stable internal environment (homeostasis) required for organisms to function.

Answer:

1. When pH is too high, the buffer system releases hydrogen ions ($H^+$) to neutralize excess hydroxide ions and lower the pH.
2. Biologically, this is essential to maintain cellular homeostasis: it preserves the optimal pH for enzyme activity, molecular structure, and normal metabolic functions, preventing cell damage or dysfunction from extreme pH shifts.