Use Of Biological Resources- Triple

Question 1

Fermentation

Answer 1

When microorganisms break down sugars to release energy usually by anaerobic respiration

Question 2

Describe how to make yogurt

Answer 2

1. Equipment is sterilised
2. Milk is pasteurised (heated up to 72 degrees for 15 seconds) then it’s cooled
3. Lactobacillus bacteria is added to the mixture and is incubated (heat to 40 degrees) in a fermenter
4. The bacteria ferments the lactose sugar in milk in the form of lactic acid
5. Lactic acid causes milk to clot and solidify into yogurt

Question 3

Fermenters

Answer 3

1. Where microorganisms are grown

2. Fermenters are full of a culture medium in which microorganisms can grow and reproduce

Question 4

pH

Answer 4

1. Is monitored and kept at the optimum level for the microorganisms’ enzymes to work efficiently
2. Keeps the rate of the reaction and product yield as high as possible

Question 5

Nutrients

Answer 5

Are needed by the microorganisms for growth are provided in the liquid culture medium

Question 6

Paddles

Answer 6

1. Stirs the mixture
2. Microorganisms are kept in contact with a fresh medium by the paddles that circulate the medium around the vessel
3. Increases product yield as microorganisms can always access the nutrients needed for growth

Question 7

Sterile air

Answer 7

1. For when the microorganisms need oxygen for respiration

2. Increases product yield as the microorganisms can always respire to provide energy for growth

Question 8

Temperature

Answer 8

1. Always monitored and kept at an optimum level

2. A water-cooled jacket makes sure it doesn’t get so hot that the enzymes denature

Question 9

Sterilising the vessels between uses

Answer 9

1. By superheated steam that kills unwanted microbes
2. Having aseptic conditions increases the product yield because the microorganism don’t have to compete with other organisms
3. Product doesn’t get contaminated

Question 10

Advantages of cloning animals

Answer 10

1. Animals that produce medicine in their milk can be cloned
2. Animals that have organs suitable for organ transplantation in humans
3. Useful genetic characteristics are always passed on

Question 11

Disadvantages of cloning animals

Answer 11

1. Might not be as healthy
2. Could have consequences that we are unaware of yet
3. difficult, time consuming and expensive