Biotechnology and genetic modification Details

Question 1

Why bacteria are useful in biotechnology and genetic modification

Answer 1

-Rapid reproduction rate
-Ability to make complex molecules
-Few ethical concerns about their manipulation and growth
-The presence of plasmids

Question 2

Anaerobic respiration in yeast during the production of ethanol for biofuels

Answer 2

-Yeast is added to a source of sugar and kept in warm conditions
-In the absence of oxygen, ethanol is produced(via anaerobic respiration)

Question 3

Anaerobic respiration in yeast during breadmaking

Answer 3

-Yeast is activated by mixing it with sugar and water
-The mixture is then added to flour to form dough
-Dough is left in a warm place to rise
-The dough rises due to trapped carbon dioxide (a product of anaerobic respiration)
-When the bread is fully cooked, high temperatures kill the active yeast and the ethanol evaporates

Question 4

Pectinase breaks down…

Answer 4

pectin(a protein found within plant cell walls)

Question 5

Use of pectinase in fruit juice production

Answer 5

Used to break down pectin within fruit cell walls in order to allow easier extraction of juice from the fruit

Question 6

Use of biological washing powders that contain enzymes

Answer 6

The enzymes break down organic substances on surfaces, making them useful for stain removal

Question 7

Use of lactase to produce lactose-free milk

Answer 7

The lactase breaks down the lactose in the milk in order to produce lactose-free milk

Question 8

Conditions for a fermenter

Answer 8

-Temperature: 24°C
-pH: low(4-6)
-Has oxygen(for aerobic respiration)
-Has sugar(for aerobic respiration)
-Has ammonium(for protein production)

Question 9

Process of genetic modification(using bacterial production of a human protein)

Answer 9

-Isolation of the DNA making up a human protein using restriction enzymes, forming sticky ends
-Cutting of bacterial plasmid DNA with the same restriction enzymes, forming complementary sticky ends
-Insertion of human DNA into bacterial plasmid DNA using DNA ligase to form a recombinant plasmid
-Insertion of recombinant plasmids into bacteria
-Multiplication of bacteria containing recombinant plasmids
-Expression in bacteria of the human gene to make the human protein

Question 10

Examples of genetic modification

Answer 10

-The insertion of human genes into bacteria to produce human proteins
-The insertion of genes into crop plants to confer resistance to herbicides
-The insertion of genes into crop plants to confer resistance to insect pests
-The insertion of genes into crop plants to improve nutritional qualities

Question 11

Advantages of genetically modifying crops

Answer 11

-Increased crop yields
-Reduced costs for food production
-Reduced need for pesticides
-Enhanced food quality
-Resistance to pests and disease

Question 12

Disadvantages of genetically modifying crops

Answer 12

-Loss of biodiversity
-Potential development of weeds which are resistant to herbicides
-Genetically modified crops are more expensive
-Genetically modified crops may contaminate wild species by crossbreeding
-Long-term health impacts are not known