2.1-2.5

Question 1

List 5 benefits to enzyme immobilisation.

Answer 1

1. Catalysis can be controlled by adding or removing enzymes promptly from the reaction mixture.
2. Enzyme concentrations can be higher.
3. Enzymes can be reused, saving money.
4. Enzymes are resistant to denaturation over greater ranges of pH and temperature.
5. Products are not contaminated by enzymes.

Question 2

List three methods of enzyme immobilisation.

Answer 2

1. Attachments to surfaces such as glass (adsorption).
2. Entrapment in a membrane or gel.
3. Aggregation by binding enzymes together into particles of up to 0.1 mm diameter.

Question 3

How does heat cause denaturation?

Answer 3

Heat causes vibrations within protein molecules that break intramolecular bonds, causing the confirmation to change.

Question 4

List 6 proteins and their function.

Answer 4

1. Rubisco: enzyme.
2. Insulin: hormone.
3. Immunoglobulin: antibody.
4. Rhodopsin: pigment.
5. Collagen: structure.
6. Spider silk : structure.

Question 5

What is Rubisco?

Answer 5

Rubisco is the enzyme that catalysed the photosynthesis reaction that fixes CO2 from the atmosphere.

Question 6

What is insulin?

Answer 6

Insulin is the hormone that is carried dissolved in blood and binds specifically and reversible to insulin receptors in the membranes of body cells, causing cells to absorb glucose and lower blood glucose levels.

Question 7

What are immunoglobulins?

Answer 7

Immunoglobulins are antibodies that bind to antigens on pathogens.

Question 8

What is rhodopsin?

Answer 8

Rhodopsin is the pigment that makes the rod cells of the retina light-sensitive.

Question 9

What is collagen?

Answer 9

Collagen is a structural protein used in skin to prevent tearing, in bones to prevent fractures, and in tendons and ligaments to give tensile strength.

Question 10

What is spider silk?

Answer 10

Spider silk is a structural protein with very high tensile strength. It also becomes stronger when stretched, so it is break-resistant.

Question 11

How do you BMI?

Answer 11

BMI = (mass in kg)/(height in m)^2

Question 12

What are the BMI limits?

Answer 12

Below 18.5: underweight
18.5-24.9: normal
25.0-29.9: overweight
Above 30.0: obese

Question 13

How do you identify lipids?

Answer 13

If they have 2 or 3 hydrocarbon chains or a quadruple ring structure.

Question 14

List three lipids.

Answer 14

1. Triglycerides
2. Phospholipids
3. Steroids

Question 15

List three polysaccharides.

Answer 15

1. Cellulose is an unbranched polymer of beta-D-glucose.
2. Starch is a helical alpha-D-glucose.
3. Glycogen is a branched polymer of alpha-D-glucose.

Question 16

List 4 properties of water.

Answer 16

• cohesive because of hydrogen bonds between them.
• adhesive because water is polar so it can adhere to polar/hydrophobic surfaces.
• thermal because the strong hydrogen bonds give water a high melting and boiling point.
• solvent because it’s polar.

Question 17

Define metabolism.

Answer 17

Metabolism is the web of all enzyme-catalysed reactions.

Question 18

Define catabolism.

Answer 18

Catabolism is the break down of complex molecules into simpler ones.

Question 19

Define anabolism.

Answer 19

Anabolism is the synthesis of complex molecules from simpler ones.