Metabolic Pathways Flashcards
What is a metabolic pathway?
They are enzyme controlled reactions within a cell
What kind of routes can a metabolic pathway have?
Reversible, irreversible, alternative steps
Types of reactions within a metabolic pathway:
Anabolic and catabolic
Definition of anabolic reaction:
They build up large molecules from small molecules and requires energy
Definition of catabolic reaction:
They break down large molecules into smaller molecules and releases energy
When does induced fit occur?
It occurs when the active site changes shape to better fit the substrate after the substrate binds
What is metabolic pathways controlled by?
They are controlled by the presence or absence of particular enzymes and the regulation of the rate of reaction of key enzymes
What does induced fit and the role of the active site of an enzyme affect?
Activation energy and the affinity of the substrate and products for the active site
What are the types of controls of enzymes within a metabolic pathway?
Competitive, non-competitive and feedback inhibition
What is a competitive inhibitor?
It binds at the active site stopping the substrate from binding. It can be reversed by increasing substrate concentration.
What is non-competitive inhibitors?
They bind away from the active site but change the shape of the active site stopping the substrate from binding. It cannot be reversed by increasing substrate concentration.
What is a feedback inhibitor?
It occurs when the end-product in the metabolic pathway reaches a critical concentration. The end-product then inhibits an earlier enzyme, blocking the pathways. So stops further synthesis of the end-product.
