Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology A-level OCR Yr13 > biotech and cloning > Flashcards

biotech and cloning Flashcards

1
Q

what is a clone?

A

genetically identical organism or cell

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

Describe natural cloning/ vegetative cloning?

A

-vegetative propagation
-involves perennating organs which enable plant to survive in adverse conditions.
-perennating organs contain food from photosynthesis and can remain dormant in the soil. They help plants survive through changing seasons.

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

Natural plant cloning occurs in?

A

-bulbs
-runners
-rhizomes
-stem tubers

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

Describe bulbs

A

e.g daffodil, leaf base swells with stored food from photosynthesis. Buds form internally which develop into new shoots and new plants in the next growing season.

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

Describe runners

A

e.g strawberry or spider plant. A lateral stem grows away from the parent plant and roots develop where the runner touches the ground. A new plant develops- the runner eventually withers away leaving the new individual independent.

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

Describe Rhizomes

A

e.g marram grass. A rhizome is a specialised horizontal stem running underground, often swollen with stored food. Buds develop and form new vertical shoots which become independent plants.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Describe stem tubers

A

e.g potato. The tip of an underground stem becomes swollen with stored food to form a tuber or storage organ. Buds on the storage organ develop to produce new shoots.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why is a rooting hormone often applied to the base of the cutting?

A

to encourage growth of new roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the advantages of using propagation instead of seeds?

A

-faster: time for planting and cropping is reduced
-guarantees the quality of the plant as genetically identical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Disadvantages of propagation?

A

lack of genetic variation which is not helpful during climate change and new disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is micropropagation?

A

process of making large numbers of genetically identical offspring from a single parent plant using tissue culture techniques.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Micropropagation is used when a desirable plant…

A

-does not readily produce seeds
-doesn’t respond well to natural cloning
-is very rare
-has been genetically modified or selectively bred with difficulty
-is required to be ‘pathogen free’ by growers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Explain the process of micropropagation and tissue culture?

A

-take sample of tissue from plant (meristem tissue and axial buds) in sterile conditions to avoid contamination
-sample is sterilised by immersing it in sterile agents (e.g bleach, ethanol)
-explant is placed in sterile culture medium containing plant hormones (auxins and cytokinins) which stimulate mitosis. Cells proliferate forming callus.
-callus is divided and separate clumps are transferred to a new culture medium contains a different mixture of hormones which stimulate development of genetically identical platelets
-plantlets are potted into compost which grow to produce a crop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Arguments for propagation?

A

-rapid production of large number of genetically identical crops which yield good crops
-culturing meristem tissue produces disease free plants
-large production of sterile and seedless plants
-enables growth of infertile plants
-can increase rare or endangered plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Arguments against propagation

A

-monoculture, genetically identical
-expensive process
-explants and platelets are vulnerable to infection
-if source of material is infected with virus, so will all the clones
large numbers of new plants can be lost in the process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the main form of cloning in vertebrates?

A

monozygotic twins (identical twins)- the early embryo splits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe cloning in invertebrates?

A

many animals can regenerate from fragments of the original

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are the two methods used in the production of cloning vertebrates?

A

artificial twinning and somatic nuclear transfer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe artificial twinning process (in cows)

A

-cow with desirable traits is treated with hormones to super-ovulate
-ova can be fertilised naturally or by artificial insemination
-mature eggs are removed and fertilised by top-quality semen
-embryo is split manually
-each embryo is grown in a lab then each embryo is implanted into a surrogate mother

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

why is one embryo implanted into one surrogate mother?

A

there are fewer risks but in pigs, more are implanted as they naturally produce litters. The body might reject and reabsorb a single foetus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is an enucleated egg cell?

A

an oocyte which has had its nucleus removed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the process of somatic cell nuclear transfer?

A

1) the nucleus is removed from an adult somatic cell
2)nucleus is removed from a mature ovum from same species
3) The nucleus from the adult somatic cell is placed into the enucleated ovum and given a mild electric shock so it fuses and begins to divide
4)embryo develops and is implanted into a third animal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Arguments for animal cloning

A

-fast production of high yielding farm animals
-genetically modified animals can be produced at a large scale
-production of rare, endangered animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Arguments against animal cloning

A

-inefficient: takes many eggs to produce one offspring
-many cloned animals fail to develop
-cloned animals have a short lifespan
-no animal welfare
-lack of genetic diversity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is reproductive cloning?

A

production of genetically identical individuals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is biotechnology?

A

using living organisms or parts of living organisms in an industrial process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

biotechnology often involves use of what?

A

enzymes (biological catalysts)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

why are microorganisms ideal in biotechnology?

A

-no welfare issues
-there is a large range of microorganisms capable of carrying out many different chemical syntheses or degradations that can be used
-genetically engineering allows us to artificially manipulate microorganisms
-microorganisms have a short life cycle and rapid growth rate- large quantities can be made in a short time.
-nutrient requirements or microorganisms are often very simple and cheap.
-bioprocess is relatively cheap as high temp and pressure is not needed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Disadvantages of using microorganisms in biotechnology?

A

-if conditions are not ideal, microorganisms won’t grow properly and work efficiently
-processes have to be sterile to prevent growth of other microorganisms which may cause disease
-ethical issues worth the use of GM organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Describe bread as a product of biotechnology (indirect food production)

A

-microbe used is Saccharomyces cerevisiae (species of yeast)
-yeast respires anaerobically (glucose-> ethanol + CO2)
-ethanol evaporates and CO2 makes bread rise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Describe how cheese is a product of biotechnology (indirect food production)

A

-bacteria called lactobacillus converts lactose into lactic acid which lowers pH.
-renin enzyme is added to separate the protein from the milk
-blue cheese has added fungus

32
Q

Describe how beer is a product of biotechnology (indirect food production)

A

-microbe used is Saccharomyces cerevisiae (species of yeast)
-yeast respires anaerobically (glucose-> ethanol + CO2)

33
Q

Describe how yoghurt is a product of biotechnology? (indirect food production)

A

-bacteria called lactobacillus converts lactose into lactic acid which lowers pH.
-proteins denature changing the texture

34
Q

What is best know single celled protein? (direct food production)

A

Quorn made from fungus Fusarium venetatum which is grown in large fermenters using glucose syrup as a food source. The microorganisms are combined with albumen (egg white) then compressed.

35
Q

What are the advantages to using microorganisms to produce food?

A

-microorganisms reproduce fast and produce protein faster than animals and plants
-microorganisms have a high protein content with little fat
-microorganisms can use waste materials, reducing cost
-microorganisms can be genetically modified
-production of microorganisms can be met with demand
-no welfare issues

36
Q

Disadvantages of using microorganisms to produce human food?

A

-if conditions are not optimum, toxins can be produced
-microorganisms have to be separated from nutrient broth and processed
-need for sterile conditions adds to costs
-many people have concerns about eating GM food
-protein must be purified
-make people dislike eating microorganisms from waste
-needs additives

37
Q

what was the first antibiotic?

A

penicillin produced from mould called Penicillium notatum

38
Q

Describe how industrial fermenters are used to produce drugs (e.g penicillin, antibiotics, insulin enzymes)

A

-mixture is continuously stirred to keep it oxygenated
-rich nutrient medium
-growth medium contains a buffer to maintains a ph around 6.5
-bioreactors are around 25-27 degrees

39
Q

What are the problems with using insulin from the pancreas of pigs?

A

-supply was dependent on the demand for meat
-allergies
-religious

40
Q

what is bioremediation?

A

Bioremediation is a branch of biotechnology that employs the use of living organisms, like microbes and bacteria to decontaminate affected areas. Two approaches include using natural organisms and GM organisms.

41
Q

Describe bioremediation using natural organisms?

A

many microorganisms naturally breakdown organic material producing carbon dioxide and water. Nutrients can be added to water to encourage microbial growth.

42
Q

Describe bioremediation using GM organisms?

A

GM bacteria are being made to break down or accumulate contaminants

43
Q

What are the risks when culturing a microorganism?

A

-risk of mutation taking place making the strain pathogenic
-there may be contamination with pathogenic microorganisms from the environment

44
Q

Describe the nutrient medium when culturing microorganisms

A

can be liquid form (nutrient broth) or solid form (agar). Nutrients allow rapid multiplication. Must be aseptic.

45
Q

Describe how to inoculate nutrient broth

A

-make suspension of bacteria to be grown
-mix a known volume with the sterile nutrient broth in the flask
-stopper the flask with cotton wool to prevent contamination from air
-incubate at a suitable temp, shaking regularly to aerate broth, providing oxygen for growing bacteria

46
Q

Describe how to inoculate agar?

A

-wire inoculating loop must be sterilised by holding it in a bunsen flame until it glows red hot.
-dip sterilised hoop in bacterial suspension and make zig zag streak across agar surface
-place lid on Petri dish with tape but not sealed completely so oxygen can get in. incubate at suitable temp

47
Q

Describe the four stages of growing bacterial colonies?

A

-the lag phase when bacteria are adapting to their new environment. They are synthesising necessary enzymes.
-the log or exponential phase is when the rate of bacterial reproduction is close or at theoretical maximum
-stationary phase when total growth rate is zero- number of new cells formed by binary fission is cancelled out by the number of cells dying
-decline/ death stage when reproduction has almost ceased and death rate increases

48
Q

what limiting factors prevent exponential growth in a culture of bacteria?

A

-nutrient level become insufficient to support further growth
-oxygen levels
-temperature: if temperature is too high, enzymes can denature, killing microorganisms
-build up of waste (toxic) can inhibit growth
-changes in pH affects enzyme activity

49
Q

what formula do you use to calculate the size of a population during log phase?

A

N (population number)= N0 (initial population number) times 2 to the power of n (number of doubles noting bacteria divides every 20 mins)

50
Q

Describe the aseptic techniques

A

-close doors and windows
-hair back
-be quick
-flaming to sterilise
-lip placed at an angle

51
Q

what is a primary metabolite?

A

compounds that are directly involved in the metabolic pathways of an organism necessary for its growth, development, and reproduction. It is produced during the growth phase. E.g amino acids, enzymes, ethanol, ethanoic acid.

52
Q

what is a secondary metabolite?

A

organic compounds that are produced by various organisms that are not directly involved in the growth, development, or reproduction of the organism but are essential in the ecological and other activities. They are usually produced during stationary phase. Although they are not important for survival, secondary metabolites might be important for other activities like protection, competition, and species interaction. E.g penicillin and other antibiotics

53
Q

What are the two main ways of growing microorganisms?

A

batch fermentation and continuous fermentation

54
Q

Describe batch fermentation

A

-microorganisms are inoculated into a fixed volume
-as growth takes place, nutrients are used up and both new biomass and waste products build up
-stationary phase (secondary metabolites)
-process is stopped before death phase and products are harvested. Whole system is sterilised and new batch culture is started.

55
Q

Describe continuous fermentation

A

-microorganisms are inoculated into sterile nutrient medium and start to grow
-sterile nutrient medium is added continuously and reaches exponential growth
-culture broth is continuously removed (products and waste products), keeping volume in bioreactor constant.

56
Q

What factors need to be controlled in a bioreactor?

A

-temperature (effect on enzyme activity so temp sensors are used)
-nutrients and oxygen
-mixing things up: mixing mechanism ensures all microorganisms receive enough food and oxygen
-asepsis (aseptic units prevent contamination from other microorganisms)

57
Q

what are the advantages of using isolated enzymes?

A

-less wasteful
-more efficient
-more specific
-less downstream processing

58
Q

Why are extracellular enzymes used more commonly in industrial processes than intracellular enzymes?

A

-cheaper
-extracellular enzymes are secreted, making them easier to isolate and use
-extracellular enzymes are easier to identify and isolate as there aren’t many compared to intracellular enzymes
-extracellular enzymes can cope with greater variations in pH and temperature.

59
Q

Why are intracellular enzymes occasionally used in industrial processes?

A

-there is a greater range of intracellular enzymes so they can be more specific

60
Q

What are immobilised enzymes?

A

enzymes attached to an inert support system over which the substrate passes and is converted to product.

61
Q

Advantages of immobilised enzymes?

A

-can be reused (cheaper)
-reduced down streaming process as reactants and products are easily separated (cheaper)
-more reliable
-greater temperature tolerance as enzymes are stabilised
-easily manipulated

62
Q

Disadvantages of immobilised enzymes?

A

-reduced efficiency
-higher initial costs of material
-higher initial costs of bioreactor
-more technical issues

63
Q

what are the methods of immobilising enzymes?

A

-adsorption
-entrapment
-covalent/ ionic
-membrane seperation

64
Q

Describe the method of surface immobilisation using adsorption to inorganic carriers (e.g cellulose, silica)? (advantages and disadvantages)

A

-relies on temporary bonds (e.g ionic, hydrogen, hydrophobic)
Advantages:
-simple and cheap process
-can be used for many different processes
Disadvantages:
-enzymes can be lost from matrix easily

65
Q

Describe the method of surface immobilisation through covalent and ionic bonding to inorganic carriers?- Advantages and disadvantages

A

-covalent bonding e.g carriers with amino, hydroxyl, carboxyl groups
-ionic bonding e.g polysaccharides such as cellulose, synthetic polymers
Advantages:
-enzymes less likely to be lost as it is strongly bound (more permenent)
-pH and substrate concentration have little effect on enzyme activity
Disadvantages:
-expensive
-active site can be modified making it less effective (blocked active site)

66
Q

Describe the method of entrapment in matrix e.g activated carbon, gelatin- advantages and disadvantages

A

advantages:
-applicable to many processes
Disadvantages:
-expensive
-difficult
-slow (diffusion)

67
Q

Describe membrane separation as a method of immobilising enzymes- advantages and disadvantages

A

advantages:
-simple
-small effect on enzyme activity
-applicable to many processes
disadvantages:
-expensive
-slow (diffusion)

68
Q

what immobilised enzyme is used to make semi-synthetic penicillin?

A

immobilised penicillin acylase is used to make semi-synthetic penicillin from naturally produced penicillin. Many bacteria which are resistant to natural penicillin are still vulnerable to semi-synthetic penicillin

69
Q

What immobilised enzyme is used to produce fructose from glucose?

A

immobilised glucose isomerase. Fructose is much sweeter than glucose and is used as a sweetener.

70
Q

what immobilised enzyme is used to produce lactose-free milk?

A

immobilised lactase- hydrolyses lactose to glucose and galactose

71
Q

what immobilised enzyme is used to produce pure samples of L amino-acids?

A

immobilised aminoacylase. Pure L amino-acids used in the production of pharmaceuticals, cosmetics and food

72
Q

what immobilised enzyme is used to produce glucose syrup from starch?

A

immobilised glucoamylase which catalyses the breakdown of dextrins (short chain polymers of starch) into glucose.

73
Q

what immobilised enzyme is used to produce acrylamide?

A

immobilised nitrile hydratase. Acrylonitrile is hydrated to form acrylamide. Acrylamide is used in the plastics industry.

74
Q

How do you produce plant clones from cuttings?

A

-cut shoot from healthy plant
-cut stem at a slant between the nodes
-dip in rooting powder/ plant hormone/ auxin
-place in soil/compost and add water
-to reduce transpiration, cover with plastic bag

75
Q

what is grafting?

A

-a method of artificial plant cloning
-joining the shoot of one plant to the growing stem and root of another plant.
-cut at an angle to increase surface area for adhesion

Biology A-level OCR Yr13 (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions