Enzyme action Flashcards
What are enzymes?
Globular proteins that act as catalysts.
What do catalysts do?
They alter the rate of chemical reactions, and are not used up.
Define activation energy.
The minimum amount of energy required to activate the reaction.
What is the specific site that is functional on an enzyme?
The active site.
What does the active site form?
A small depression within the much larger enzyme molecule.
What is the substrate?
The molecule on which the enzyme acts on.
What is the ESC?
The enzyme-substrate complex. This is when the substrate fits neatly into the depression of the active site. The substrate molecule is held within the active site by bonds that temporarily form between certain amino acids of the active site and the groups on the substrate molecule.
What does the induced fit model propose?
That the active site forms as the enzyme and substrate react.
How does the active site form in the induced fit model?
The proximity of the substrate leads to a change in the enzyme that forms the functional active site. As it changes shape, the enzyme puts a strain on the substrate molecule which distorts a particular bond or bonds in the substrate and consequently lowers the activation energy
Explain the lock and key model.
A substrate will only fit the active site of one particular enzyme, the shape of the substrate fits exactly into the active site .
Which bonds maintain the enzymes shape?
Hydrogen bonds.
Define catalyst.
A substance that speeds up a reaction and provides an alternative pathway in a reaction by lowering the activation energy, without being used up.
Why are enzymes effective in small quantities?
All can form ESCs and become saturated.
