NANP Board Practice Exam

What are the major metabolic pathways for carbohydrate regulation influenced by?

1. Genetics and lifestyle choices

2. Dietary fiber

3. Hormonal influences and allosteric regulation

4. Physical exercise

The correct answer is: Hormonal influences and allosteric regulation

The correct answer highlights the essential roles that hormonal influences and allosteric regulation play in the metabolic pathways that govern carbohydrate regulation. Hormones such as insulin and glucagon are pivotal in maintaining blood glucose levels. Insulin facilitates the uptake of glucose by cells, while glucagon promotes the release of glucose when energy is needed. Allosteric regulation refers to the way enzymes adjust their activity based on the binding of molecules at different sites, which can be crucial for metabolic control. For example, the enzyme phosphofructokinase is influenced by ATP and AMP levels, regulating glycolysis and thereby influencing carbohydrate metabolism. While genetics, lifestyle choices, dietary fiber, and physical exercise can impact metabolic health and carbohydrate utilization, they do not directly regulate the metabolic pathways in the same immediate and systemic way that hormones and allosteric modulation do. This makes the focus on hormonal influences and allosteric regulation particularly relevant in understanding the intricacies of carbohydrate metabolism.