Enzymes

Question 1

What are enzymes made of?

Answer 1

Protein

Question 2

What are enzymes also known as?

Answer 2

Biological catalyst

Question 3

Characteristics of enzymes

Answer 3

• sensitive to temperature (works best at optimum temp)
• sensitive to pH (stomach - acidic; small intestines - alkali)
• can be reused
• denatures at high temperature
• specific

Question 4

Function of enzymes

Answer 4

Speeds up reactions

Question 5

How does the lock and key mechanism work?

Answer 5

1. The substrate connects to the active site of the enzyme
2. An enzyme-substrate complex is formed
3. The substrate is broken down as a product while the enzyme remains the same

Question 6

Enzymes found in the mouth

Answer 6

Amylase; turns starch to maltose

Question 7

Enzymes found in the stomach

Answer 7

Pepsin; turns protein to polypeptide

Question 8

Enzymes found in milk

Answer 8

Rennin; turns caseinogen (milk) to casein (coagulated milk)

Question 9

Enzymes found in the pancreas

Answer 9

• Pancreatic amylase; turns starch to maltose
• Trypsin; turns polypeptide to peptide
• Lipase; turns lipid droplets to glycerol + fatty acid

Question 10

Enzymes under carbohydrase

Answer 10

• amylase
• maltase
• fructase
• lactase
• sucrase

Question 11

Enzymes under protease

Answer 11

• polypeptide
• peptide/ amino acid

Question 12

What is catalase?

Answer 12

• product of chemical reaction in the organism
• cells produce enzyme to breakdown hydrogen peroxide into water and oxygen

Question 13

What produces hydrogen peroxide?

Answer 13

Plants and animals

Question 14

What are the factors affecting enzyme activity

Answer 14

Temperature
pH
Enzyme concentration
Substrate concentration

Question 15

How does temperature affect enzyme activity?

Answer 15

• the more the heat, the more kinetic energy
• needs to be optimum temperature (at the peak of the graph)
• too high temperature = enzyme denatured

Question 16

How does pH affect enzyme activity?

Answer 16

• enzymes have optimum pH (at the middle of the graph)
• increase or decrease of H+ in acid or OH- in alkaline can interfere with enzyme structure

Question 17

How does enzyme concentration affect enzyme activity?

Answer 17

• high enzyme concentration = high rate of reaction
• stays constant until substrate is limited

Question 18

How does substrate concentration affect enzyme activity?

Answer 18

• high enzyme concentration = high rate of reaction
• stays constant until all of the active site of enzymes are used