C1.1 Enzymes & metabolism Flashcards
(19 cards)
What is an enzyme?
A biological catalyst that speeds up the rate of a reaction without being used themselves
Name the most recent hypothesis on enzyme action
Induced fit model
What is metabolism?
The complex network of interdependent and interacting chemical reactions occurring in living organisms
What is the 1st step in aerobic respiration?
Glycolysis
What happens in anabolic reactions?
Enzymes bring the substrate molecules together, build larger molecules (condensation reaction)
What happens in catabolic reactions?
The enzyme active site affects the bonds in the substrates so they are easier to break smaller molecules (hydrolysis)
What are the 2 types of enzyme action?
Intracellular - inside of cells
Extracellular - outside of cells
Describe the enzyme structure
- globular protein
- specifically shaped active site
What does the ‘lock and key’ model suggest?
Assumes that the active site is rigid in shape
What does the ‘induced fit’ model suggest?
Suggests the active site is always flexible
What causes denaturation?
Extreme pH
Heat
Presence of heavy metals
What does denaturation destroy in an enzyme?
Tertiary or quaternary conformation of a protein
What makes a substance acidic?
Hydrogen ions
What makes a substance alkaline?
Hydroxide ions
What is activation energy?
The amount of energy needed to start a reaction
What factors other than pH, temp and presence of heavy metals affect enzyme activity?
- substrate concentration
- enzyme concentration
What is activation energy used for?
break or weaken the bonds in the substrate
How to conduct an enzyme controlled rate of reaction experiment
- Choose an enzyme
- Determine the substrate
- Decide what to measure
- Choose independent variable
- Identify control variable
What is the formula for rate?
Product formed OR reactant used/ time
