enzymes

Question 1

definition and function of enzymes

Answer 1

1. made of proteins
2. speeds up rate of chemical reaction
3. remain chemically unchanged

Question 2

digestive enzymes

Answer 2

• amylase - digests starch to maltose
• maltase - digests maltose to glucose
• protease - digests proteins to polypeptides, then to amino acids
• lipase - digests fats to fatty acids and glycerol

Question 3

IMPORTANT!!

explain why enzymes are specific in action, using lock and key hypothesis

Answer 3

• enzymes have specific 3D shape and active site
• its substrate has a 3D shape complementary to its active site
• forming enzyme-substrate complex

Question 4

how are enzymes affected by temperature

Answer 4

• an enzyme is less active at low temperatures, the rate of the substrate molecule colliding with the enzyme is very low
• as the temperature increases, the rate of enzyme reaction increases, the rate of effective enzyme collision is increased, which increases the enzyme-substrate complex formation
• optimum temperature for most human enzymes : 40-45C
• increasing temperature above the optimum causes a rapid decrease in the rate of enzyme reaction ie. the enzyme denature upon exposure to temperatures above its optimum temperature

Question 5

definition of denaturation

Answer 5

the change in the three-dimensional structure of an enzyme or any other soluble protein, caused by heat or chemicals such as acids or alkalis