Flashcards
Enzyme inhibitors
Cards in this deck (18)
- 1What are the 2 types of enzyme inhibitors?- Competitive
- Non-competitive - 2What does the control of metabolic activity within cells do?Regulates rate and quantity of product formation
- 3What activates and inactivates enzymes?Activate = Cofactors
Inactivate = Inhibitors - 4What happens in competitive inhibition?- Molecule with similar shape fits into active site
-Blocks substrate entering active site
- Enzyme cant carry out function - 5Why is it called competitive inhibition?Substrate and inhibitor molecules compete to get to active site
- 6What happens to the rate of reaction?- Number of substrates binding to active site decreases so rate of reaction is slowed
- 7What does the degree of inhibition depend on?The relative concentrations of substrate, inhibitor and enzyme.
- 8What is the effect on the rate of reaction?- Reduces rate of reaction but does not change Vmax.
- If substrate conc. is increased there will be more substrate than inhibitor so original Vmax can still be reached. - 9How do statins work?- Inhibitor of enzymes used in synthesis of cholesterol.
- Reduces blood cholesterol conc. - 10How does aspirin work? (Irreversible)- Inhibits active site of COX enzymes
- Prevents synthesis of prostaglandins and thromboxone (chemicals that produce pain and fever) - 11What is non- competitive inhibition?- Inhibitor binds to allosteric site
- Tertiary structure of enzymes changes so the active site changes shape.
- Stops substrate from fitting into active site.
- Function cannot be carried out. - 12What is the effect on the rate of reaction from this?- Increased conc. of enzyme or substrate will not overcome effect of inhibitor.
- Increased conc. of inhibitor decreases rate of reaction. - 13What are irreversible inhibitors?Cannot be removed and are often toxic.
- 14How do organophosphates work?- Used in insecticides and herbicides
- Inhibits enzyme acetyl cholinesterase (necessary for nerve impulse transmission)
- Leads to muscle crams, paralysis and death - 15How do proton pump inhibitors work?- Treat long term indigestion
- Block enzyme system responsible for secreting hydrogen ions into stomach
- Reduces production of excess acid - 16What is end-product inhibition?Enzyme inhibition that occurs when the product of a reaction acts as an inhibitor to the enzyme that produces it (negative feedback control mechanism)
- 17What happens as a result of end-product inhibition?- Excess product not made
- Resources not wasted - 18What is end-product inhibition an example of?Non-competitive reversible inhibition
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- AS level Biology (Chapter 04 - Enzymes) Flashcards on Enzyme inhibitors, created by Bethany Westwood on 02/12/2016.
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- Bethany Westwood
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