Metabolic Pathways: Key Area 1.6 Flashcards
What are metabolic pathways controlled by?
The presence or absence of particular enzymes
What can rates of enzyme reactions be controlled by?
Intracellular and extracellular signal molecules
What do anabolic pathways require?
Energy and it involes biosynthetic processes
What do catabolic pathways do?
Release energy and invoke the breakdown of molecules
What does the activity of enzymes depend on?
Their flexible and dynamic shape
What do substrate molecules have?
An affinity for the active site of an enzyme
Describe induced fit
as the substrate starts to bind, the active site changes shape to fit the substrate more closely, increasing the rate of reaction
What is activation energy?
The energy required to initiate a chemical reaction
What affect to enzymes have on activation energy
They lower it
What do products of enzyme reactions have?
A low affinity for the active site of the enzyme
What affects the direct and rate of an enzyme reaction?
The concentration of substrate and end product
What is a non competitive inhibitor?
The inhibitor does not fit into the active site of the enzyme, so binds go another part of the enzyme molecule. This changes the shape of the active site so it can no longer combine with the substrate molecule.
What is a competitive inhibitor?
Competitive inhibitors have a similar structure shake to the normal substrate of the enzyme, and so can fit into its active site. They compete with substrate molecules for a position in the active site on the enzyme
What is feedback inhibition?
A method of metabolic control in which the end product binds to an enzyme that catalysed a reaction early in the pathway
