BIOTECHNOLOGY & GENETIC MODIFICATION

Question 1

State uses of microorganisms

Answer 1

• Microorganisms can be used by humans to produce foods and other useful substances

Question 2

What is the most common type of microorganisms

Answer 2

Bacteria

Question 3

1. Why is bacteria useful?

Answer 3

because they are capable of producing complex molecules

Question 4

State an example of bacteria producing complex molecules

Answer 4

certain bacteria added to milk produce enzymes that turn the milk into yoghurt

Question 5

2. Why is bacteria useful?

Answer 5

They are also useful because they reproduce rapidly, meaning the amount of chemicals they can produce can also rapidly increase

Question 6

3. Why is bacteria useful?

Answer 6

There are few ethical considerations to growing them in large numbers in the laboratory

Question 7

4. Why is bacteria useful?

Answer 7

They possess plasmids

Question 8

What are plasmids?

Answer 8

Plasmids are small, circular loops of DNA which can be an ideal way of transferring DNA from one cell to another during genetic manipulation

Question 9

What is yeast?

Answer 9

Yeast is a single celled fungus that uses sugar as its food source

Question 10

What happens when yeast respires?

Answer 10

When it respires, ethanol and carbon dioxide are produced (and energy is released)

Question 11

State the symbol equation for anaerobic respiration in yeast

Answer 11

C6H12O6= 2C2H50H +2CO2

Question 12

State the word equation for anaerobic respiration in yeast

Answer 12

glucose= ethanol + carbon dioxide

Question 13

What is ethanol in the equation being used as?

Answer 13

A biofuel

Question 14

What is a biofuel

Answer 14

a fuel made from living organisms rather than a fossil fuel like oil, coal or gas

Question 15

What is used as the substrate for producing ethanol

Answer 15

plant material; as a source of glucose

Question 16

How is ethanol formed

Answer 16

Plant material is chopped up into small pieces and mixed with yeast which respires anaerobically and produces ethanol. The liquid is separated from the remaining solids and any water is removed, leaving a concentrated solution of ethanol.

Question 17

When will yeast respire anaerobically

Answer 17

When there is excess of sugar even if oxygen is available

Question 18

How are plants harvested for producing ethanol?

Answer 18

Sometimes, waste parts of plants are used but in other places, crops are grown specifically to be harvested for making ethanol.

Question 19

What is the effect does growing plants specifically for the production of ethanol?

Answer 19

It causes a reduction in land available for local people to grow food crops needed for survival.

Question 20

How does bread rise?

Answer 20

The carbon dioxide produced by fermentation (anaerobic respiration) of glucose makes bread dough rise.

Question 21

How is fruit juice made?

Answer 21

Chopping the fruit before squeezing helps to release a lot more juice but this does not break open all the cells so a lot of juice is lost

Question 22

What is the name of the enzyme used in fruit juice production to break down cells so more juice is released

Answer 22

Pectinase

Question 23

How does pectinase work?

Answer 23

It breaks down a chemical called pectin that is found inside plant cell walls. Once pectin is broken down, the cell walls break more easily and more juice can be squeezed out of the fruit.

Question 23

How does pectinase work?

Answer 23

It breaks down a chemical called pectin that is found inside plant cell walls. Once pectin is broken down, the cell walls break more easily and more juice can be squeezed out of the fruit.

Question 24

State another job of pectinase

Answer 24

Pectinase can also make juice clearer as large polysaccharides like pectin can make the juice seem cloudy so once they are broken down into smaller molecules, the juice becomes clearer

Question 25

What is the effect of detergents that only contain soap

Question 26

What is the effect of detergents that only contain soap

Question 27

What is the effect of detergents that only contain soap

Answer 27

Detergents that only contain soap can remove some of these stains when mixed with hot water, but it can take a lot of time and effort and very high temperatures to remove the stain entirely

Question 28

What are biological washing powders

Answer 28

They contain enzymes similar to the digestive enzymes produced in the alimentary canal that help to break down large food molecules

Question 29

Advantages of using biological washing powders