Unit 2-Metabolic Pathways And Their Control Flashcards
What are metabolic pathways?
Metabolic pathways are enzyme-catalysed reactions within a cell.
What is meant by an
All of the metabolic pathways in an organism
What are the two types of metabolic pathways?
Anabolic and catabolic.
Metabolic activity which synthesises (builds up) complex molecules, requires energy.
Anabolic
Metabolic activity which breaks down complex molecules, releases energy.
Catabolic
A gap in the membrane caused by a channel forming protein.
Pore
A protein found in the phospholipid membrane which carries molecules across via active transport.
Protein pump
The energy required to start a chemical reaction
Activation Energy
The region of an enzyme which allows the substrate to bind
Active Site
The result of an enzyme catalysed reaction
Product
The substance on which the enzyme acts.
Substrate
The reaction can take place in more than one direction
Reversible
Occurs when the active site changes shape to better fit the substrate after the substrate binds.
Induced fit
The attraction of a substrate (high) or product (low) to the active site of an enzyme.
Affinity
Three types of inhibition
Competitive inhibition
Non-competitive inhibition
Feedback inhibition
Competitive inhibition
Inhibitor molecule binds to the active site of the enzyme and stops the substrate from binding
What property of a competitive inhibitor allows it to compete with the substrate?
They have a similar molecular shape allowing them to bind to the enzyme’s active sites.
How can competitive inhibition be reversed?
By increasing substrate concentration.
Non-competitive inhibition
Inhibitor does not bind to the active site but does bind to a different part of the enzyme and changes the active site shape.
Will increasing substrate concentration reverse non-competitive inhibition?
No
Feedback inhibition
End product in a metabolic pathway binds to an enzyme at the start of the pathway stopping metabolic pathway
