enzymes Flashcards
What is an Enzyme?
An enzyme is a protein that functions as a biological catalyst a substance that speeds up a chemical reaction without being changed by the reaction.
Properties of enzymes
1) Enzymes are globular proteins
2) Every Enzyme has a binding site called its active site
3) Enzymes are affected by temperature and level of PH value
4) enzymes are specific
Examples of enzymes “ase”
Sucrase(enzyme)– Sucrose( substrate)=glucose + Fructose
Lipase (enzyme)—- Lipids (substrate)= fatty acids & glycerol
Pancreatic Amylase(enzyme)– starch (substrate)= Maltose
Maltase (enzyme)- Maltose (substarte)= Glucose
Explain The lock and Key model
- -Enzymes are folded into complex shapes that allow smaller molecules to fit them. The places where these molecules fit is called the active site.
- In the lock and key model, the shape of the active site matches the shape of its substrate molecules. This makes enzymes highly binded specific- each type of enzyme can catalyze only one type of reaction.
- some enzymes break apart one molecule into two smaller molecules, but other enzymes join small molecules together to make a larger one.
What 2 factors can affect the rate of an Enzyme-catalyzed reaction?
1) PH Value
2) Temperature
describe the effects of temperature level in enzymes
- The rate of an enzyme-catalyzed reaction increases as the temperature increases.
- – However, at optimum temperatures, the rate slows down and the reaction stops because the enzyme becomes denatured ( active site changes) and can no longer function as a biological catalyst.
describe the effects of PH Value in enzymes
– Changes in PH alter the shape of an enzyme’s active site.
—Different enzymes work best at different PH values.
— The optimum pH of an enzyme depends on where it normally works.
For example, intestinal enzymes have an optimum ph value of 7.5
but stomach enzymes have an optimum pH of 2
