Enzymes Flashcards
What are enzymes and what do they do?
Biological catalysts that speed up the rate of biochemical reactions.
How do enzymes form enzyme-substrate complexes? (4)
- Enzyme and substrate collide
- Substrate binds to the active site IF they are complementary - this is lock and key theory
- Enzyme-substrate complex is formed
- Substrates are released as products and active site is now free to bind to other substrates
How does pH/temperature affect enzymes? (5)
- Low pH/temp - substrate and enzymes are not at their optimum so their kinetic energy is low and no successful collisions will occur
- As pH/temp increases towards optimum S and E will gain KE - collisions occur more frequently and successfully
- Once the optimum is reached, rate of collisions will reach its peak. Max number of E.S complexes are formed
- Active site begins to denature - no longer be complementary to shape of substrate so it will no longer bind. Rate decreases
- Active site denatures fully - S’s can no longer bind to active site. ROR stops
How does substrate concentration affect enzymes? What does its graph look like? (5)
- S.C is low so enzymes are in excess - ROR is slow b/c there are not enough collisions
- As S.C increases, more E.S complexes can form - ROR will increase
- Enzymes can only catalyse one reaction at a time b/c only one substrate can occupy the active site - ROR will plateau
- ROR will remain constant until S’s are released as products. Active site will be free to to bind and catalyse new substrates
- A cliff.
What is salivary amylase?
Enzyme produced in the salivary glands that breaks down starch into maltose
What is protease?
Enzyme produced in the pancreas that breaks down protein into amino acids
What is lipase?
Enzyme produced in the pancreas that breaks down lipids into fatty acids and glycerol
What is pancreatic amylase?
Enzyme produced in the pancreas that breaks down starch into maltose
What is maltase?
Enzyme produced in the small intestine that breaks down maltose into glucose.
