Enzymes Flashcards
What are anabolic reactions?
Larger molecules built up from smaller ones
Give examples of anabolic reactions
Protein synthesis and making polysaccharides
What are catabolic reactions?
Larger molecules are broken down
Give some examples of catabolic reactions
Digestion
Give an equation for metabolism
Catabolism + anabolism
What is a catalyst?
A substance that increases the rate of a reaction while remaining chemically unchanged itself
What are enzymes?
Biological catalysts
What is a substrate?
A molecule that binds to the active site of an enzyme to form an enzyme-substrate complex
What is the active site?
The small part of the enzyme that binds to its specific substrate and causes catalysis
Explain the induced fit hypothesis
Shape of the active site moulds to the substrate which is not an exact fit to start with. Binding with the active site causes the shape to change slightly so that it’s complementary
What is the activation energy?
The energy barrier that must be overcome before reactants reach their temporary transition state
How do enzymes increase the rate of reaction
Lowers the activation energy by offering an alternative reaction pathway which has a lower activation energy
Why are enzymes so specific?
Precise tertiary shape
Active site has specific shape
Substrate must be complementary with this
What is the transition state?
The unstable intermediate molecules form before the become products
What factors affect the rate of reactions on enzymes?
Temperature
pH
enzyme concentration
substrate concentration