Concept:Metabolic pathways are tightly controlled by specific rate-limiting enzymes that can be turned on or off via allosteric regulation, preventing the over-accumulation of products.
Solution:- Hexokinase is the crucial first enzyme in the glycolysis pathway.
- It phosphorylates glucose to trap it inside the cell.
- It is highly regulated via feedback inhibition (inhibited by its own product, glucose-6-phosphate), making it a classic textbook example of a regulatory (allosteric) enzyme.
Why other options are incorrect:Maltase, sucrase, and urease are simple digestive/hydrolytic enzymes. They generally operate continuously based solely on substrate availability and lack the complex allosteric regulatory sites found in pathway gatekeepers like hexokinase.
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