**Question:** In response to change in pH, increase glutaminase activity is due to

**Core Concept:** Glutaminase is an enzyme that plays a crucial role in regulating ammonia levels in the body, particularly in the liver, where it plays a role in ammonia detoxification. The liver maintains a delicate balance of pH, as an imbalance can lead to severe liver dysfunction and other associated complications. The question is asking about the relationship between pH change and glutaminase activity.

**Why the Correct Answer is Right:** When the pH changes in the liver, the enzyme activity of glutaminase can be affected. Among the given options, option C states that glutaminase activity increases due to a decrease in pH. In the liver, a decrease in pH generally indicates acidosis, which activates the enzyme, H+/K+-ATPase, responsible for pumping protons (H+) into the liver cells to neutralize the acidic environment. This increase in H+ concentration leads to the activation of glutaminase, which increases ammonia detoxification and helps maintain liver function.

**Why Each Wrong Option is Incorrect:**

A. This option suggests that glutaminase activity increases with a decrease in pH, which contradicts the correct option C. In reality, a decrease in pH activates the H+/K+-ATPase and not glutaminase.

B. Correct option C explains the increase in glutaminase activity due to pH changes in the liver, whereas option B does not address the relationship between pH and glutaminase activity.

D. This option incorrectly states that glutaminase activity increases with an increase in pH. In reality, a decrease in pH activates glutaminase in the liver to neutralize the acidic environment.

**Clinical Pearl:**

Understanding the relationship between pH and glutaminase activity is crucial for maintaining liver function and ammonia detoxification. An imbalance in pH can lead to various liver diseases and liver dysfunction, emphasizing the importance of understanding the correct answer and avoiding the misconceptions present in options A, B, and D. Glutaminase activation in response to pH changes helps the liver adapt to varying acid-base conditions, ensuring proper ammonia detoxification and maintaining liver health.