Unit 21 - Biotechnology & Genetic Modification

Question 1

What is the most common type of micro-organisms used in biotechnology?

Answer 1

Bacteria

Question 2

Why are bacteria useful in biotechnology?

Answer 2

• Capable of producing complex molecules.
• They reproduce rapidly.
• There are few ethical considerations (when growing them in large numbers in labs).

Question 3

Bacteria possess plasmids. Why is this useful in biotechnology?

Answer 3

Plasmids are an ideal way of transferring DNA from one cell to another during genetic manipulation.

Question 4

Plasmids

Answer 4

Small, circular loops of DNA.

Question 5

Yeast

Answer 5

A single celled fungus that uses sugar as its food source.

Question 6

How does yeast respire?

Answer 6

Anaerobically.

Question 7

Anaerobic respiration in yeast - WORDS EQUATION

Answer 7

Glucose → Ethanol + Carbon Dioxide

Question 8

Anaerobic respiration in yeast - CHEMICAL EQUATION

Answer 8

C6H12O6 → 2C2H5OH + 2CO2

Question 9

What, in anaerobic respiration in yeast, is used as a biofuel?

Answer 9

Ethanol (alcohol)

Question 10

What are everyday products made with biotechnology?

Answer 10

• Biofuels
• Bread
• Biological washing powders
• Fruit juice production

Question 11

When will yeast respire anaerobically?

Answer 11

When it has access to plenty of sugar.

Question 12

What product of anaerobic respiration in yeast is used to make bread dough rise?

Answer 12

Carbon dioxide (it’s caught in the dough, and this causes the bread to rise)

Question 13

Fruit juice is produced by squeezing the fruits to remove the juice. What enzyme can you add to make more juice?

Answer 13

Pectinase.

Question 14

How does pectinase work?

Answer 14

• It breaks down a chemical called pectin, which is found in plant cell walls.
• Once pectin is broken down, the cell walls break more easily and so more juice can be squeezed from the fruit.
• Pectinase also helps produce clearer juice

Question 15

What enzymes do biological washing powders have?

Answer 15

Similar to digestive enzymes.

Question 16

Advantages of biological washing powders.

Answer 16

• Effective at lower temperatures - so less energy and money is required.
• Can be used to clean delicate fabrics that would’t be suitable for high temperature washing.

Question 17

Where is lactose found?

Answer 17

Milk.

Question 18

What is the enzyme (which babies are born with) that breaks down lactose?

Answer 18

Lactase

Question 19

What does it mean to be lactose intolerant?

Answer 19

People who lose the ability to produce lactase.

Question 20

What’s lactase?

Answer 20

The enzyme that breaks down lactose.

Question 21

Symptoms of lactose intolerance:

Answer 21

• Nausea
• Flatulence
• Diarrhoea

Question 22

How can you make milk lactose free?

Answer 22

By adding lactase to it (so that it breaks down the lactose).

Question 23

Lactose is a disaccharide. (bonus - What is a disaccharide?)

Answer 23

A disaccharide is any substance that is composed of two molecules of simple sugars.

Question 24

State the process of lactose being broken down.

Answer 24

Lactose —lactase—> Galactose and Glucose

Question 25

When and by who was penicillin first discovered?

Answer 25

1928 by Alexander Fleming.

Question 26

Penicillin

Answer 26

The first antibiotic.

Question 27

What is penicillin produced by?

Answer 27

By the fungus Penicillium.

Question 28

How does penicillin work?

Answer 28

It produces a chemical to prevent it being infected by certain types of bacteria.

Question 29

Penicillin is produced on a large scale using an…

Answer 29

Industrial fermenter.

Question 30

What are fermenters?

Answer 30

Containers used to grow microorganisms like bacteria and fungi in large amounts.

Question 31

Advantage of using a fermenter:

Answer 31

Conditions can be carefully controlled to produce large quantities of the exact right type of microorganism.

Question 32

Mycroprotein

Answer 32

The process of creating food from a fungus.

Question 33

Genetic modification

Answer 33

Changing the genetic material of an organism by removing, changing or inserting individual genes from another organism.

Question 34

The gene for human insulin can be inserted into bacteria which then produce human insulin. This can then be collected and purified for medical use to treat people with…

Answer 34

Diabetes.

Question 35

Examples of genetic modification:

Answer 35

Crop plants (eg. wheat and maize) have been genetically modified to:
- resistant to insect pests.
- resistant to certain herbicides.

Question 36

Restriction enzymes

Answer 36

USed to isolate the required gene, leaving it with ‘sticky ends’.

Question 37

What are ‘sticky ends’?

Answer 37

A short section of unpaired bases.

Question 38

DNA ligase enzyme

Answer 38

Joins the plasmid and the isolated gene together.

Question 39

Advantages of GM crops:

Answer 39

• better for the environment
• cheaper
• increased crop yields

Question 40

Disadvantages of GM crops:

Answer 40

• costs more
• reduce biodiversity
• increased dependency on certain chemicals (like herbicides that crops are resistant to).