M6 C22: cloning and biotechnology

Question 1

what is a natural clone?

Answer 1

genetically identical copies of something

Question 2

what are some examples of natural clones

Answer 2

mitosis in cells
yeast budding
binary fission

Question 3

advantages of natural clones?

Answer 3

don’t need a mate
pass on advantageous alleles quicker
conditions that are good for parents are good for the offspring

Question 4

disadvantages of natural clones?

Answer 4

lack of variation
could lead to wipe out by a pathogen
offspring overcrowded
selection not possible
susceptible to change

Question 5

what is vegetative propagation?

Answer 5

plants that can reproduce asexually by cloning as they have many cells that retain the ability to differentiate

Question 6

what are some examples of vegetative propagation?

Answer 6

runners- strawberry plants, spider plants
suckers- old branch may die and the new branch replaces it
Bulbs – underground stem
Tubers – underground stem. One potato can grow into one or more plants.

Question 7

why is it importsnt to use thin slices of organisms when viewing plants under a microscope?

Answer 7

In preparations several cells thick the light must travel through the other cell layers, reducing the quality of the image, and at low magnifications several cells could a layered image of several cells at once.

Question 8

what is tissue culture?

Answer 8

groeing new tissues, organ or plants from certain tissues cut from sample plants

Question 9

what is micro propagation?

Answer 9

growing a large number of plants from meristem tissue taken from a sample

Question 10

when is it useful to use microproagation?

Answer 10

The desirable plant doesn’t:
Produce many seeds
respond well to natural cloning
Rare
GM or selectively bred
Needs to be pathogen free

Question 11

how is micro propagation done?

Answer 11

cells took from ex plant
sterilized before placed onto growth medium which contains glucose, amino acids, phosphates
they form a callus culture
divides to produce lots of undifferentiated cells
transferred to a new medium to grow with hormones
transferred to compost once stable

Question 12

what are advantages of micro propagation?

Answer 12

Rapid compared to growing from seed
Disease free plants
Increase numbers of rare plants
Large numbers of seedless plants (bananas and grapes)
Naturally infertile plants can be grown (e.g. Orchids)

Question 13

what are disadvantages of micro propagation?

Answer 13

Monoculture – genetically identical (susceptible to the same diseases/growing conditions)
Expensive and requires skilled workers
Explants and plantlets are vulnerable to mould during the process
If source materials infected with a virus, all new plants are infected

Question 14

what is the process of tissue culture?

Answer 14

root cut into small discs
root discs pressed onto a dish contasining agar jelly
kept in an incubator
callus develops and transferred to new dish of agar
after several weeks this form tiny plants which are then tranferred to a flask with nutrients

Question 15

what is an example of cloning in animals?

Answer 15

Identical twins - a fertilised egg (zygote) splits into two.

Question 16

what are some invertebrates that can clone?

Answer 16

Starfish can regenerate an entire organism from just a fragment of the original

Sponges and flat worms create clones as part of their natural reproductive cycle

Hydra produce small buds on the side of their bodies that eventually live independently

Question 17

what is the process of artifical embryo twinning?

Answer 17

1- A fertilised egg (zygote) is created using IVF​
2- The zygote divides by mitosis to form a ball of cells
3- Cells are separated and allowed to continue dividing
4- Each mass of cells is placed into the uterus of a surrogate mother
5- offsrping is given birth to naturally by a surrogate

Question 18

what is Somatic Cell Nuclear Transfer Cloning?

Answer 18

The egg cell has its nucleus removed which is then fused with the nucleus of a normal cell due to an electric shock
the zygote then divides by mitosis into lots of embryo cells
the embryo is then implabted into the surrogate and then is given birth to like a natural birth

Question 19

what are some uses of cloning?

Answer 19

Mass producing animals with desirable characteristics.
Producing animals that have been genetically engineered to produce human products
Producing human embryos to supply stem cells

Question 20

what are some disadvantages of animal cloning?

Answer 20

many are born abnormally large
Health problems
Very few embryos survive until birth- can be distressing if the surrogate has a misscarriage

Question 21

what are some advantages for animal cloning?

Answer 21

Desirable genetic characteristics always passed on​

Infertile animals can be reproduced​

Do not need to wait for breeding season​

Increase population of endangered species​

Develop new treatments for disease

Question 22

what are some disadvantages for cloning?

Answer 22

Very difficult to do, time-consuming and expensive​

No genetic variability – all susceptible to the same disease​

Undesirable characteristics always passed on ​

Evidence suggests that clones may not live as long as natural offspring

Question 23

what is fermentation?

Answer 23

Microorganisms can be grown under controlled conditions in larger fermenters

The product of fermentation is either the microorganisms itself e.g. mycoprotein, or a product produced by the microorganism e.g. insulin

Question 24

what is batch fermentation?

Answer 24

Microorganisms are grown in batches in the fermentation vessel

Once the culture cycle is complete, the product is removed, the fermenter is cleaned and a new batch of microorganisms is grown. Process stopped before death phase and products harvested​

This is known as a closed culture

Question 25

what is continuous fermentation?

Answer 25

Microorganisms are continually grown and the products harvested thry are made during normal growth (primary metabolite) Nutrients are added and waste is removed throughout the culturing process

Question 26

how is brewing used with yeast?

Answer 26

Malting – barley germinates, enzymes are produced that break starch into sugars for yeast to respire​ Mashing – malt mixed with hot water(55-65°C); enzymes break down starch producing wort; hops added for flavour Fermentation – yeast added to wort; fermentation occurs; yeast eventually killed as pH lowers, ethanol builds up and oxygen decreases​ Maturation – beer conditioned for 4-29 days (2-6°C)​ Finishing – beer filtered, pasteurised, bottled/canned.

Question 27

how does yeast respire?

Answer 27

Glucose -> ethanol + carbon dioxide (sugar) (alcohol)

Question 28

how is yeast used in baking?

Answer 28

yeast respires aerobically the carbon dioxide produced makes the bread rise. Active yeast mixture is added to flour and other ingredients; left in a warm environment to rise Dough is ‘knocked back’ (excess air removed), kneaded, shaped and allowed to rise again Cooked in a hot oven so CO2 bubbles expand Yeast cells are killed during cooking

Question 29

how is bacteria used in cheese making?

Answer 29

bacteria are fed on lactose a sugar found in milk to produce lactic acid Lactose -> lactic acid

Question 30

what is the process of cheese being made with bacteria/

Answer 30

Milk is pasteurised - heated to 95°C for 20 seconds to kill off natural bacteria Milk is homogenised – fat droplets evenly distributed​ Bacteria and chymosin enzyme are added Milk separates into solid curds and liquid whey

Question 31

what are the curds from the milk used for?

Answer 31

Cottage cheese – curds are packaged and sold​ Harder cheese – curds cooked in the whey and strained through a cheese cloth and may be pressed/ matured

Question 32

what is the whey used for from the milk?

Answer 32

Whey – used in animal feeds

Question 33

how is yoghurt produced?

Answer 33

Bacteria are fed on lactose a sugar found in milk to produce lactic acid Lactose -> lactic acid

Question 34

what is the process of yoghurt production?

Answer 34

Sterilisation of equipment (heat to 71oC for 20s to kill bacteria) Pasteurisation of milk Add bacteria culture and incubate (Lactobacillus) Sampling Addition of flavours, colours and packaging Quality control and take some culture to add to the next batch

Question 35

how is penicillin made?

Answer 35

produced by batch culture as it is only produced once the population has reached a certain size. (it is a secondary metabolite) The fermenter is run for 6- days, it is then filtered to remove the cells Potassium compounds are then added and the penicillin precipitated as crystals The antibiotic is then prepared for administration as tablets, syrup or injection.

Question 36

how is synthetic insulin produced?

Answer 36

produced by genetically modifying bacteria. The human gene for producing insulin is inserted into a bacterium using a plasmid as a vector. The resulting genetically modified bacteria can then produce vast quantities of insulin. Insulin is produced using a continuous process.

Question 37

what is Bioremediation?

Answer 37

use of microorganisms to clean the soil and underground water on polluted sites. Microorganisms convert toxic substances to less harmful substances.

Question 38

what is Single-cell protein (SCP)?

Answer 38

microorganisms can be used to produce proteins for human consumption as food​ Many different fungi can be used to create proteins with similar amino acid profiles to that of plants and animals. They can grow on almost any organic substrate including waste including paper and whey (curdled milk after the curds have been removed)​ ## Footnote an example of this is quorn

Question 39

advantages of using microorganisms to make food for human consumption?

Answer 39

Production of a protein can be much faster than if made by an animal or plant​ Production can be increased/ decreased according to demand​ No animal welfare issues​ Protein contains no animal fat or cholesterol​ Microorganisms can be GM to adjust the amino acid content of the protein​ Not affected by seasonal variations​ Not much land is needed​

Question 40

disadvantages of using microorganisms to make food for human consumption​

Answer 40

Some people may not want to eat fungal protein or food grown on waste​ Need to isolate the protein from the medium it is grown in ​ Protein has to be purified​ Culture can become infected easily due to optimum growing conditions​ Different taste/texture to traditional protein source

Question 41

what is biotechnology?

Answer 41

use of organsism in technology to make a useful prooduct

Question 42

what is aseptic technique?

Answer 42

reduce likelihood of contamination with unwanted bacteria or fungi.​

Question 43

how can we ensure aseptic technique?

Answer 43

Washing hands​ Disinfect working area​ Bunsen burner operating near by ( heats air, causes air to rise and prevents air born microbes from settling)​ Flaming the necks of bottles as they are opened and closed to prevent bacteria entering (also glass/metal equipment)​ Only slightly lift lid on the petri dish​

Question 44

what is innoculation?

Answer 44

The act of introducing microorganism or suspension of microorganisms (e.g. bacteria) into a culture medium​

Question 45

What is incubation?

Answer 45

providing conditions for optimal growth of microbiology cultures

Question 46

what is the lag phase?

Answer 46

where a small number of individuals reproduce

Question 47

what is the log phase?

Answer 47

exponential growth Ever-increasing number of individuals reproduce. The population doubles per unit time

Question 48

what is the stationary phase?

Answer 48

Population growth declines until it remains stable with cyclic fluctuations.

Question 49

what is the death phase?

Answer 49

Nutrients run out, waste builds up Eventually all will die

Question 50

what are some examples of limiting factors that can inhibit bacteria growth?

Answer 50

Food Shelter Light Water Oxygen Accumulation of toxic waste Disease Predators

Question 51

what are immoblised enzymes?

Answer 51

enzymes that cant move anywhere because they are attached and held in place by a susbstrate

Question 52

advanatges of using immobilised enzymes?

Answer 52

can be reused no contamination of enzymes into product cheap to carry out withstand higher ph / temps as the bonds and active site cant break as they are held in place

Question 53

disadvanatges of using immbolised enzymes?

Answer 53

Specialist expensive equipment is required Immobilised enzymes are more costly to buy, so are unlikely to be financially worthwhile for smaller industries The rate of reaction is sometimes lower when using immobilised enzymes as the enzymes cannot freely mix with the substrate

Question 54

what are 3 main methods of immoblising enzymes?

Answer 54

adsorption covalent bonding entrapment

Question 55

what is adsorption?

Answer 55

porous support such as clay or glass beads bind to ewnxymes it has hydrophobic interactions and ionic links. active site is accessible but can be changed due to the bonds.

Question 56

what is covalent bonding?

Answer 56

enzymes bonding onto suporting surface using strong covalent bonds could distortrt the acgtive site, expensive however is less likely to leak

Question 57

what is entrapment?

Answer 57

enzyme trapped in gel like substance. active site not as accessible, longer process however there is no change to an active site as susbstrate has to diffuse in and out

Question 58

Glucose isomerase?

Answer 58

Converts glucose to fructose Produces high fructose corn syrup- much sweeter than sucrose Often used in diet foods Cheaper than sucrose

Question 59

Penicillin acylase?

Answer 59

Formation of semi-synthetic penicillins e.g. amoxicillin and ampicillin Some penicillin resistant microorganisms are not resistant to these

Question 60

Lactase?

Answer 60

Lactose -> glucose and galactose by hydrolysis Used to produce lactose free milk

Question 61

Aminoacylase

Answer 61

Used to produce pure samples of L-amino acids by removing the acyl group from the nitrogen of an N-acyl-amino acid L-amino acids are the building blocks for the synthesis of a number of: Pharmaceutical compounds Agrochemical compounds Additives for food

Question 62

Glucoamylase

Answer 62

Converts dextrins to glucose During the hydrolysis of starch, short polymers of glucose (dextrins) are formed. Can be immobilised on a variety of surfaces and used to digest sources of starch e.g. corn and cassava​ Used also to ferment starch pulp to alcohol to produce gasohol Also to make high fructose corn syrup

Question 63

Nitrile hydratase

Answer 63

Converts nitriles to amides including acrylonitrile to acylamide Acrylamide can be polymerised to form polyacryamide (plastic used as a thickener) can be used to treat water – sticks small contaminants together so they can be precipitated and easily filtered Also used in paper making and gel for electrophoresis