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Flashcards in chapter 3 Deck (8):

What do catalysts do?

Catalysts alter the rate of a chemical reaction without undergoing permanent changes themselves. They can be used repeatedly and are therefore effective in small amounts.


What is activation energy?

An initial boost of energy that is needed to kick start the reaction. It is the minimum amount of energy needed to activate the reaction.


What is an active site?

The small region of the enzyme that is functional which is made up of a relatively small number of amino acids. It forms a small, hollow depression within the much larger enzyme molecule


What is the substrate?

The molecule on which the enzyme acts


How is the enzyme-substrate complex formed?

The substrate molecule is held within the active site by bonds that temporarily form between certain amino acids of the active site and groups on the substrate molecule.


Why is the induced fit model a better explanation of the scientific observations?

- it explains how other molecules can affect enzyme activity
- how the activation energy is lowered


What does the competitive inhibitor do?

A competitive inhibitor will block the enzyme's active site (ie: it will occupy the same space as the natural substrate, blocking it from being catalyzed)


What does the non-competitive inhibitor do?

A non-competitive inhibitor will bind to the enzyme somewhere other than the active site of the enzyme. This will change the shape of the enzyme such that the natural substrate may or may not be able to bind to the enzyme's active site, but the enzyme won't be able to complete the chemical reaction necessary.