Unit 1.4 Enzymes Flashcards
Define enzymes
Proteins that have a specific structure (active site) complimentary to their substrate
They catalyse metabolic reactions without being used up/changed during the reaction
What do most enzyme names end in?
ase
What type of protein are enzymes?
Tertiary
How do enzymes have specific 3D/globular shapes?
Cuz of their sequence of amino acids
What are intracellular enzymes?
they act in solutions inside cells
Example of intracellular enzymes?
Hydrolases inside lysosomes which hydrolyse substances taken into cell
What are extracellular enzymes?
they act outside cells
Example of extracellular enzymes?
Digestive enzymes released from cells by exocytosis into the alimentary canal such as amylase
Explain how some rando ass chemical reaaction slows down from that hydrogen peroxide experiment thingy
- Rate of chemical reaction depends on freq. of successful collisions between the substrate + active site
- Freq. in number of collisions per second. Start of reaction, many substrate molecules, so there’s high freq. of successful collisions between substrate + active site.
- Results in a rapid initial rate of reaction
- As reaction takes place some substrate converted to product and amount of substrate molecules falls. Chances of substrate molecules colliding with active site decreases; makes reaction slow down
- Finally all substrate molecules converted, no more molecules left to collide w/ active site + reaction stops
Initial rate vs rate over 30s, why initial faster?
Conc. of substrate higher at start, most active site occupied, more enzyme substrate complexes, more product made per unit of time
pH stand for?
Potential hydrogen
State 2 factors of 2 things that must be controlled when investigating the effect of pH on the activity of an enzyme
Temp. and conc. of substrate and enzymes
What are inhibitors?
Substance that slows down/stops enzyme action
What are competitive inhibitors?
- They got similar shape to substrate molecules
- Allows them to bind to active site
- They block active site so substrate molecules cannot enter
How to decrease effect of inhibitor?
Add more substrate
