21. Biotechnology and Genetic Engineering Flashcards

1
Q

How can microorganisms be used by humans?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the most common type of microorganism which is used in biotechnology?

A

The most common type of microorganisms used in biotechnology are bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why are bacteria commonly used in biotechnology?

A

They are useful because they are capable of producing complex molecules

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is an example of a complex molecule that bacteria can create?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is yeast and what does it use as its food source?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is produced when yeast respires?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q
  1. What is the ethanol from the respiration of yeast used for?
    (biofuels)
A

The ethanol produced in this reaction is increasingly being used as a biofuel (a fuel made from living organisms rather than a fossil fuel like oil, coal or gas)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
  1. What is used as the substrate to create biofuels?(biofuels)
A

Plant material is used as the substrate for producing ethanol (as a source of glucose)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
  1. What is done with the plant material?
    biofuels
A

it is chopped up into small pieces and mixed with yeast which respires anaerobically and produces ethanol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  1. What is done with the liquid produced by this reaction?
    biofuels
A

The liquid is separated from the remaining solids and any water is removed, leaving a concentrated solution of ethanol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q
  1. What is sometimes done with the waste parts?
    biofuels
A

Sometimes the waste parts of crop plants, such as the stalks or outer leaves, are used, but in other places, crops are grown specifically to be harvested for making ethanol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q
  1. What concerns are there relating to biofuels?
A

In some places, this is causing concern that there is less land available for local people to grow food crops needed for survival

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
  1. In what way can yeast respire if it has access to lots of sugar?
    (bread making)
A

Yeast will respire anaerobically if it has access to plenty of sugar, even if oxygen is available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
  1. How does yeast respiring anaerobically help bread making?
    bread making
A

the yeast is mixed with flour and water and respires anaerobically, producing carbon dioxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q
  1. What product of this reaction will help in bread making?
    bread making
A

The carbon dioxide produced by the yeast during respiration is caught in the dough, causing the bread to rise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q
  1. What is the chemical equation for the anaerobic respiration of yeast?
A

C6H12O6 –> 2C2H5OH + 2CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q
  1. How is fruit juice produced?
    fruit juice production
A

Fruit juice is produced by squeezing the fruits to remove the juice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q
  1. Why is this method (squeezing fruits) not effective?
    fruit juice production
A

Chopping the fruit up 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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q
  1. What enzyme can be used to help in fruit juice production?
    (fruit juice production)
A

By adding an enzyme called pectinase to the chopped up fruit, more juice is released

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q
  1. How does Pectinase help?
    fruit juice production
A

Pectinase works by breaking down a chemical called pectin that is found inside plant cell walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q
  1. What does pectin do?
    fruit juice production
A

Once pectin is broken down, the cell walls break more easily and more juice can be squeezed out of the fruit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q
  1. Apart from producing more juice, what quality of the juice does Pectinase change? How?

(fruit juice production)

A

Adding pectinase to fruits also helps to produce a clearer juice as larger polysaccharides like pectin can make the juice seem cloudy – once they are broken down into smaller molecules, the juice becomes clearer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q
  1. What are many of the stains on clothes made from?
    biological washing powders
A

Many stains on clothes are organic molecules – oil from skin, protein from blood, fat and protein from food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q
  1. Why are detergents that only contain soap not so effective at removing stains?
    (biological washing powders)
A

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 stains entirely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q
  1. What type of washing powders are better and what do they contain?
    (biological washing powders)
A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q
  1. What are 3 advantages of using biological washing powders?
    (biological washing powders)
A

quickly breaking down large insoluble molecules
effective at lower temperatures
can be used to clean delicate fabrics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q
  1. How do biological washing powders help to quickly break down large insoluble molecules?
    (biological washing powders)
A

Quickly breaking down large, insoluble molecules such as fats and proteins into smaller, soluble ones that will dissolve in washing water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q
  1. How is it beneficial that biological washing powders are effective at lower temperatures?
    (biological washing powders)
A

They are effective at lower temperatures, meaning less energy (and money) has to be used in order to wash clothes to get them clean as washing water does not need to be heated to higher temperatures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q
  1. How is it beneficial that biological washing powders can be used to clean delicate fabrics?
    (biological washing powders)
A

They can be used to clean delicate fabrics that would not be suitable for washing at high temperatures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q
  1. Where is lactose found?
    lactose-free milk
A

Lactose is the sugar found in milk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q
  1. What enzymes do humans produce that is related to lactose?
    (lactose-free milk)
A

Human babies are born with the ability to produce lactase, the enzyme that breaks down lactose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q
  1. What does it mean if someone is lactose intolerant?
    lactose-free milk
A

In certain areas of the world, many people lose the ability to produce lactase as they get older
This means that they can become lactose intolerant and react badly to the lactose in milk and products made from milk (cheese, yoghurt etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q
  1. What are symptoms of lactose intolerance?
    lactose-free milk
A

nausea, flatulence and diarrhoea as their digestive system is upset by the lactose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q
  1. How can milk be made lactose free?
    lactose-free milk
A

Milk can be made lactose free by adding the enzyme lactase to it and leaving it to stand for a while to allow the enzyme to break down the lactose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q
  1. What was the name of the first antibiotic and who discovered it?
A

Penicillin was the first antibiotic discovered in 1928 by Alexander Fleming

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q
  1. How was penicillin discovered?
A

He noticed that some bacteria he had left in a Petri dish had been killed by the naturally occurring Penicillium mould

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q
  1. How does penicillin mould help in destroying bacteria?
A

The penicillium mould produces a chemical to prevent it being infected by certain types of bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q
  1. How does penicillin kill bacteria?
A

it interferes with the building of the bacterial cell wall
- the cell wall of the bacteria ruptures and dies when it tries to grow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q
  1. How can penicillin be produced on a large scale?
A

Since the discovery of penicillin, methods have been developed to produce it on a large scale, using an industrial fermenter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q
  1. What are fermenters?
A

Fermenters are containers used to grow (‘culture’) microorganisms like bacteria and fungi in large amounts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q
  1. For what purposes can fermenters be used?
A

These can then be used for many biotechnological processes like producing genetically modified bacteria and the penicillium mould that produces penicillin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q
  1. What are the advantages of using a fermenter?
A

The advantage of using a fermenter is that conditions can be carefully controlled to produce large quantities of exactly the right type of microorganism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q
  1. What 6 conditions need to be controlled in a fermenter?
A

aseptic precautions
nutrients
optimum temperature
optimum pH
oxygenation
agitation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q
  1. How and why are aseptic precautions controlled in a fermenter?
A

fermenter is cleansed by steam to kill microorganisms and prevent chemical contamination, which ensures only the desired microorganisms will grow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q
  1. How and why are nutrients controlled in a fermenter?
A

nutrients are needed for use in respiration to release energy for growth and to ensure the microorganisms are able to reproduce

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q
  1. How and why is optimum temperature controlled in a fermenter?
A

temperature I monitored using probes and maintained using the water jacket to ensure an optimum environment for enzymes to increase enzyme activity (enzymes will denature if the temperature is too high or work too slowly if it is too low)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q
  1. How and is oxygenation controlled in a fermenter?
A

oxygen is needed for aerobic respiration to take place

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q
  1. How and why is optimum pH controlled in a fermenter?
A

Ph inside the fermenter is monitored using a probe to check it is at the optimum value for the particular microorganism being grown. The ph can be adjusted, if necessary, using acids or alkalis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q
  1. How and why is agitation controlled in a fermenter?
A

stirring paddles ensure that microorganisms, nutrients, oxygen, temperature and ph are evenly distributed throughout the fermenter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

In what processes can biotechnology be used?

A

to make biofuels
bread making
fruit juice production
biological washing powders
lactose-free milk
penicillin production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is genetic engineering?

A

Genetic engineering is changing the genetic material of an organism by removing, changing or inserting individual genes from another organism

52
Q

What is the organisms that receives the genetic material called?

A

The organism receiving the genetic material is said to be ‘genetically modified’, or is described as a ‘transgenic organism’

53
Q

What is DNA called that contains DNA from another organism?

A

The DNA of the organism that now contains DNA from another organism as well is known as ‘recombinant DNA’

54
Q

What are examples of genetically modified organisms?

A

bacteria modified to produce human insulin
crop plants modified to be resistant to insect pests
crops plants modified to be resistant to certain herbicides
crop plants modified to produce additional vitamins

55
Q

How can bacteria (generally) be modified to produce human insulin?

A

The gene for human insulin has been inserted into bacteria which then produce human insulin which can be collected and purified for medical use for diabetics

56
Q

How can crop plants be modified to be resistant to insect pests?

A

Crop plants, such as wheat and maize, have been genetically modified to contain a gene from a bacterium that produces a poison that kills insects, making them resistant to insect pests such as caterpillars

57
Q

How can crop plants be modified to be resistant to certain herbicides?

A

Crop plants have also been genetically modified to make them resistant to certain herbicides (chemicals that kill plants), meaning that when the herbicide is sprayed on the crop it only kills weeds and does not affect the crop plant

58
Q

How can crop plants be modified to produce additional vitamins?

A

Some crops have been genetically modified to produce additional vitamins, eg ‘golden rice’ contains genes from another plant and a bacterium which make the rice grains produce a chemical that is turned into vitamin A in the human body, which could help prevent deficiency diseases in certain areas of the world

59
Q

What are 2 advantages of GM crops?

A

reduced use of chemicals such as herbicides and pesticides - Peter for the environment - cheaper/less time-consuming for farmers
increased yields from the crops as they are not competing with weeds for resources or suffering from pest damage

60
Q

What are 5 disadvantages of GM crops?

A

increased costs of seeds
increased dependency on certain chemicals, such as the herbicides that crops are resistant to
risk of inserted genes being transferred to wild plants
reduced biodiversity
some research has shown that plants that have had genes inserted into them do not grow as well as non GM plants

61
Q

How do GM crops increase the price of seeds?

A

companies that make Gm seeds charge more for them to cover the cost of developing them this can mean smaller, poorer farmers can’t compete with larger farms

62
Q

How do GM crops cause on increased dependency on certain chemicals?

A

often made by the same companies that produce the seed and more expensive to buy

63
Q

How do GM crops create a risk for inserted genes being transferred to wild plants? How is this harmful?

A

( by pollination ) which could reduced the usefulness of the GM crop (e.g if weeds also gain the gene that makes them resistant to herbicide

64
Q

How do GM crops cause reduced biodiversity?

A

there are fewer plant species when herbicides have been used - this can impact insects and insect eating birds

65
Q
  1. What is the first step of genetic engineering? What needs to be located?
    (process of genetic engineering)
A

The gene that is to be inserted is located in the original organism (for example, this could be the gene for human insulin)

66
Q
  1. What happens once the gene is located? What is used?
    process of genetic engineering
A

Restriction enzymes are used to isolate the required gene, leaving it with ‘sticky ends’ (a short section of unpaired bases)

67
Q
  1. What is also cut using restrictive enzymes?
    process of genetic engineering
A

A bacterial plasmid is cut by the same restriction enzyme leaving it with corresponding sticky ends

(plasmids are circles of DNA found inside bacterial cells)

68
Q
  1. What happens to the plasmid and isolated gene?
    process of genetic engineering
A

The plasmid and the isolated gene are joined together by DNA ligase enzyme

69
Q
  1. Why is DNA ligase used to join the plasmid and gene?
    process of genetic engineering
A

If two pieces of DNA have matching sticky ends (because they have been cut by the same restriction enzyme), DNA ligase will link them to form a single, unbroken molecule of DNA

70
Q
  1. What is done with the now genetically engineered plasmid?
    process of genetic engineering
A

The genetically engineered plasmid is inserted into a bacterial cell

71
Q
  1. How does the genetically modified plasmid spread through the population of bacteria?
    (process of genetic engineering)
A

When the bacteria reproduce the plasmids are copied as well and so a recombinant plasmid can quickly be spread as the bacteria multiply and they will then all express the gene and make the human protein

72
Q

Where are the genetically engineered bacteria placed and why?
(process of genetic engineering)

A

The genetically engineered bacteria can be placed in a fermenter to reproduce quickly in controlled conditions and make large quantities of the human protein

73
Q

Why are bacteria extremely useful for genetic engineering?

3

A

They contain the same genetic code as the organisms we are taking the genes from
There are no ethical concerns over their manipulation and growth
The presence of plasmids in bacteria,

74
Q

Why are bacteria good for genetic engineering due to the fact that they contain the same genetic code as the organisms we are taking the genes from?

A

meaning they can easily ‘read’ it and produce the same proteins

75
Q

Why are bacteria good for genetic engineering, opposed to, for example, animals?

A

There are no ethical concerns over their manipulation and growth (unlike if animals were used, as they can feel pain and distress)

76
Q

Why are bacteria good for genetic engineering due to the fact that they contain plasmids?

A

The presence of plasmids in bacteria, separate from the main bacterial chromosome, makes them easy to remove and manipulate to insert genes into them and then place back inside the bacterial cells

77
Q

Why are bacteria useful for the biotechnology?

A

Because of their rapid reproduction rate
Their ability to make complex molecules
Lack of ethical concerns over their manipulation and growth
Genetic code shared with all other organisms
Presence of plasmids

78
Q

What is alcohol produced by fermentation used for?

A

Biofuel

79
Q

What causes bread dough to rise?

A

Yeast respires anaerobically and produces CO2

80
Q

What is pectinase used for?

A

It is an enzyme that is added to chopped up fruit and more juice is released as it breaks down the pectin which is found inside plant cell walls and therefore more juice is squeezed out

81
Q

What does Pectinase help do?

A

Produce a clearer juice as once polysaccharides are broken down into smaller molecules the juice becomes clearer

82
Q

What are many stains?

A

Organic molecules

83
Q

What do biological washing powders contain?

A

Enzymes similar to the digestive enzymes

84
Q

What are advantages of biological washing powders?

A

Quickly breaks down large insoluble molecules into smaller soluble ones that dissolve in water
They are effective at lower temps so less energy and money wasted
They can be used to clean delicate clothing

85
Q

What is lactose?

A

a sugar found in milk

86
Q

What does lactose intolerant mean?

A

React badly to dairy products- nausea, flatulence and diarrhoea as their digestive system is upset

87
Q

How can milk be made lactose free?

A

By adding the enzyme lactase to it

88
Q

What was the first antibiotic to be discovered?

A

Penicillin

89
Q

What is penicillin?

A

A chemical produced by the fungus penicillium which inhibits bacterial growth

90
Q

How have we been able to make lots of penicillin?

A

Using industrial fermenters

91
Q

What are industrial fermenters?

A

Containers used to grow microorganisms like bacteria/fungi in large amounts. Those are then used for producing genetically modified bacteria and the penicillium mould that produces penicillin.

92
Q

What are advantages of industrial fermenters?

A

Conditions are carefully controlled to produce large amounts of exactly the right type of microorganism

93
Q

How is agitation controlled in an industrial fermenter?

A

Stirring paddles ensure that microorganisms, oxygen and nutrients are evenly distributed

94
Q

How are septic precautions carried out in an industrial fermenter

A

Fermenter is cleaned by steam to kill microorganisms and prevent chemical contamination which ensures only desired microorganisms will grow

95
Q

Define Genetic Engineering

A

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

96
Q

Give examples of genetic engineering

A

The insertion of human genes into bacteria to produce human insulin
The insertion of genes into crop plants to confer resistance to herbicides and insect pests
The insertion of genes into crop plants to provide additional vitamins such as golden rice which makes the rice grains produce a chemical that is turned into Vitamin A

97
Q

What are advantages of Genetic engineering

A

Reduced use of chemicals such as herbicides

Increased yields from the crops as they are not competing with weeds

98
Q

Disadvantages of Genetic engineering

A

Increased costs of seeds- GM seeds are more expensive meaning smaller and poorer farms cannot compare with larger farms
Reduced biodiversity as there are fewer plant species when herbicides have been used
Research says that plants that have had genes inserted into them do not grow as well as non- Gm plants

99
Q

Outline the genetic engineering using bacterial production of a human protein

A

Isolation of the DNA making up a human gene using restriction enzymes, forming sticky ends
Cutting off 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 plasmid bacteria
Replication of bacteria containing recombinant plasmids which make human protein as they express the gene

100
Q

Bacteria are useful in biotechnology and genetic modification due to their

A

rapid reproduction rate
ability to make complex molecules
few ethical concerns over their manipulation and growth
the presence of plasmids

101
Q

Anaerobic respiration in yeast is used to make

A

ethanol for biofuel.

102
Q

Anaerobic respiration in yeast is used in bread making because it

A

produces carbon
dioxide and makes the dough/ bread rise.

103
Q

Pectinase digest the cell

A

wall of the fruits. This release more juice from the fruit. It
also helps to make the cloudy juice clear.

104
Q

Milk contains

A

a sugar, lactose, which many people are intolerant to. Enzyme lactase is added to milk to breakdown lactose. This results in formation of lactose-free milk.

105
Q

Bacteria and fungi can reproduce exponentially inside

A

fermenters, where they are provided with optimum temperature, pH, nutrients supply, and removal of waste
product.

106
Q

Genetic modification

A

is changing the genetic material of an organism by removing,
changing or inserting individual genes

107
Q

Process of genetic modification using bacteria:

A

isolation of the DNA making up a human gene 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 inside a fermenter expression in bacteria of the human gene to make the human protein

108
Q

Examples of genetic modification:

A

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

109
Q

Advantages of genetically modifying crops.

A

disease resistance ;
large(r) / fast(er), yield ;
drought resistance ;
herbicide resistance ;
pest/insect, resistance ;
salt resistance ;
frost resistance

110
Q

uses of bacteria in biotechnology and genetic engineering

A

bacteria are useful in biotechnology and genetic engineering because they can be grown and manipulated ed without raising any ethical concerns. the rate of reproduction is very fast and does not take much time. they have a genetic code that is the same as all other organisms, so genes from other animals or plants can be successfully transferred into bacterial DNA and use their ability to make complex molecules

111
Q

biotechnology

A

application of biological organisms, systems, or processes to manufacturing service and industries

112
Q

reasons why bacteria are useful for genetic modification

A

rapid reproduction rate
no ethical concerns
bacteria have same bases as DNA

113
Q

disadvantages of genetically modifying crops

A

will have less nutritional value. cosumers may reject geneticallt modifed crops as genes are lost and there will no variation

114
Q

why are herbicides like 2.4-D sprayed on broad level weeds?

A

tends to run off thinner leaves.

115
Q

to provide food

A

trees were cut down for agricultural land and to provide shelter for the increased human population.
intensification of agriculture included the use of insecticides, pesticides, herbicides, and monoculture
areas cleared for intensive livestock farming
use of machinery, artificial fertilizers to increase yield
selective breeding to improve the production of crop and livestock

116
Q

negative impacts of large-scale monoculture of crop plants

A

monoculture- growing of single species of plant on the same land year after year affected by the fertility and the balance of the soil- need for artificial fertilizers increases. in a monoculture, every attempt is made to destroy organisms that feed on, compete with or infect the crop plant - use of insecticide, pesticides, and herbicides. so, the balanced life of a natural plant and animal community is displaced- habitat destroyed ( loss of biodiversity)

117
Q

herbicides used

A

leach from farmland into water systems such as rivers and lakes, where they can kill aquatic plants, removing the producers from the food chain. animals migrate or get extinct

118
Q

Bacteria are useful in biotechnology and genetic modification due to their

A

rapid reproduction rate
ability to make complex molecules
few ethical concerns over their manipulation and growth
the presence of plasmids

119
Q

Anaerobic respiration in yeast is used to make

A

ethanol for biofuel.

120
Q

Anaerobic respiration in yeast is used in bread making because it

A

produces carbon
dioxide and makes the dough/ bread rise.

121
Q

Pectinase digest the cell

A

wall of the fruits. This release more juice from the fruit. It
also helps to make the cloudy juice clear.

122
Q

Milk contains

A

a sugar, lactose, which many people are intolerant to. Enzyme lactase is added to milk to breakdown lactose. This results in formation of lactose-free milk.

123
Q

Bacteria and fungi can reproduce exponentially inside

A

fermenters, where they are provided with optimum temperature, pH, nutrients supply, and removal of waste
product.

124
Q

Genetic modification

A

is changing the genetic material of an organism by removing,
changing or inserting individual genes

125
Q

Process of genetic modification using bacteria:

A

isolation of the DNA making up a human gene 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 inside a fermenter expression in bacteria of the human gene to make the human protein

126
Q

Examples of genetic modification:

A

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

127
Q

Advantages of genetically modifying crops.

A

disease resistance ;
large(r) / fast(er), yield ;
drought resistance ;
herbicide resistance ;
pest/insect, resistance ;
salt resistance ;
frost resistance