Enzymes-Taahirah Stemmet

Question 1

What are enzymes?

Answer 1

Enzymes are proteins that accelerate chemical reactions inside living cells.

Question 2

Substances that accelerate chemical reactions are known as?

Answer 2

Catalysts . therefore enzymes are biological catalysts.

Question 3

What should happen in order for a chemical reaction to occur?

Answer 3

The reaction needs activation energy to initiate the reaction . Enzymes lower the activation energy of a reaction, thereby accelerating the reaction.

Question 4

Chemical reactions that take place in living cells are known as metabolic reactions. There are two types of metabolic reactions . what are those two reactions?

Answer 4

Anabolic reactions

Catabolic reactions

Question 5

What is an anabolic reactions?

Answer 5

During this type of reaction , a complex molecule is built up from simple molecules . Energy is usually.
required. Anabolic reaction is the opposite to catabolic reaction.

Question 6

What is a catabolic reaction?

Answer 6

A complex molecule is broken down into simple molecules . Energy is usually released.

Question 7

Some e.g of digestive enzymes .

should included one from carbohydrates ( disaccharides and polysaccharides ) lipids and proteins

Answer 7

Carbohydrates :
-disaccharides :
maltose + water = maltose= glucose + glucose
-polysaccharides:
starch + water = amylase =
Lipids:
lipids + water = lipase = glycerol + 3 fatty acids
Proteins :
proteins + water = protean e.g pepsin = smaller polypeptides

Question 8

Enzymes action

Answer 8

During a chemical reaction , a substance(s) is/are changed from one form to another .

Question 9

What is the substance in which the enzymes act ?

Answer 9

Substrate. Enzyme are specific - substrates , in other words enzymes can only act on a specific substrate .

Question 10

What is the active site ?

Answer 10

There is a specific region on the enzymes known as the active site . The substrate molecule fits into the enzyme
active site as a key fits into a lock . This ensures the specificity of the enzymes .

Question 11

temperature

Answer 11

• Enzymes are very sensitive to temperature change .
• Low temperatures make enzymes temporarily inactive.
• The temperature at which enzymes work best is optimum temperature i.e 35 to 40 degrees in humans ( body temperature is 37)
• Temperature usually above 45 degrees , the shape begins to change and the substrate no longer fits into the active site .