Summary 5.5

-activation energy is a starting energy

-enzymes are the main catalysts of chemical reactions.

-catalysts speed up chemical reactions.

-enzymes does not supply activation energy but instead, it lowers the energy requirement barrier that reaction is resulted in normal cell temperature.

-a specific reactant acted upon by an enzyme is enzyme's substrate.

-sustrate fits into a region called active site.

-fit between sustrate and enzyme is not rigid.

-way that an enzyme can lower activation energy is by accepting tow reatant molecules in do adjacent sites.

-like proteins, enzyme's shape is senstive to changes in its environment.

Concept Check 5.5

1.Explan the role of activation energy in a reaction. How does an enzyme affect activation energy?

Activation energy is a start up energy tat activates reactant. It is the main catalyst of te reaction.

2.Describe how a substrate interacts with an enzyme.

If it fits into a region of the enzymes called active site. the region changes shape for it to fit.