ISSA Nutritionist Practice Exam

What role does the liver play in relation to glucose?

1. It produces glucose

2. It absorbs glucose from the gut

3. It serves as a reservoir for glucose

4. It breaks down glucose into fat

The correct answer is: It serves as a reservoir for glucose

The role of the liver in relation to glucose is multifaceted, but one of its key functions is to serve as a reservoir for glucose. This is primarily accomplished through processes like glycogenesis, where the liver converts excess glucose from the bloodstream into glycogen for storage. When blood sugar levels drop, the liver can then convert this glycogen back into glucose through glycogenolysis, releasing it into the bloodstream to maintain adequate blood glucose levels. While the liver does play a role in glucose production and regulation through gluconeogenesis (the synthesis of glucose from non-carbohydrate sources), its ability to store glucose in the form of glycogen is crucial for ensuring energy availability between meals. This storage capability is particularly important for maintaining blood sugar homeostasis and providing energy when dietary carbohydrates are not immediately available. In terms of the other choices, glucose absorption from the gut occurs primarily in the intestines rather than the liver. Although the liver does produce some glucose and can convert glucose into fat (lipogenesis), stating that it specifically breaks down glucose into fat oversimplifies its metabolic functions and does not capture the primary role of glucose storage.