6.2.1 cloning and biotechnology

Question 1

how do plants produce clones of themselves naturally and what is this process called
6.2.1(a)

Answer 1

vegetative reproduction-allows them to reproduce asexually by mitosis

Question 2

what parts of a plant can natural cloning occur from
6.2.1(a)

Answer 2

tubers, rhizomes, bulbs and runners

Question 3

how do you naturally clone plants by taking a cutting
6.2.1(a)

Answer 3

1. steralise a pair of scissors and cut stem at a 45 degree angle to maximise SA for root growth
   2.remove most of the leaf
   3.dip end in rooting powder
   4.place in water then cover with a transparent bag to reduce transpiration
2. Give time for the cuttings to develop roots and plant it leaving you with a genetically identical plant

Question 4

3 advantages of vegatative propagation
6.2.1(a)

Answer 4

-easier to harvest
-used to grow plants that are difficult to grow from seeds
-can be done at any time of the year

Question 5

what are 2 disadvantages of taking cuttings
6.2.1(a)

Answer 5

-clones can be killed by 1 disease
-limited number of clones produced by one plant

Question 6

what is the process of artificial cloning in plants called
6.2.1(b)

Answer 6

micropropagation

Question 7

describe the process of micropropagation
6.2.1(b)

Answer 7

1. cut meristem tissue which contains totipotent cells-called explant
   2.steralise sample with alcohol
   3.explants are placed in a steralise liquid containing growth hormone which allows them to undergo mitosis creating a callus
2. callus is divided and each is moved into a different tube containing growth hormones and nutrients which allows plantlets to form
   5.plantlets are placed in compost in a greenhouse

Question 8

what are some advantages of artificial cloning of plants
6.2.1(b)

Answer 8

-easier to harvest
-used to grow plants that are difficult to grow from seeds
-can be grown at any time of the year

Question 9

what are some disadvantages of artificial cloning of plants
6.2.1(b)

Answer 9

-clones can be killed by a single disease
-expensive
-requires skill
-can fail due to contamination with pathogens

Question 10

how do you get monozygotic twins
6.2.1(c)

Answer 10

sperm fertilises egg and Zygote plits into 2 daughter cells

Question 11

how can animals reproduces asexually
6.2.1(c)

Answer 11

mitosis

Question 12

what is the main advantage of asexual reproduction
6.2.1(c)

Answer 12

if conditions are good then all offspring should be equally adapted to the good condition and therefore have high fitness

Question 13

what are 2 ways artificial cloning occurs
6.2.1(d)

Answer 13

embryo twinning
somatic cell nuclear transfer

Question 14

describe the process of embryo twinning
6.2.1(d)

Answer 14

Artificially fuse an egg and sperm together forming a zygote
The zygote undergoes mitosis to form an embryo
Split the embryo into separate cell masses
Allow the cell mass to undergo mitosis to form an embryo and place into the uterus of the mother

Question 15

describe somatic cell nuclear transfer
6.2.1(d)

Answer 15

1.extract somatic body cell from the adult you want be cloned ad extract nucleus from body cell
2.take unfertalised egg from another animal and extract nucleus (enucleation) you then have a enucleated egg
3.electrofusion takes place which shock the nucleus into the enucleated cell
4.egg divides by mitosis and forms an embryo
5.put embryo in surrogate who then gives birth

Question 16

what are 3 arguments for artificial cloning in animals
6.2.1(d)

Answer 16

-clone animals with desired characteristics
-clone genetically modified animals for medicine
-harvest stem cells to grow organs and tissues

Question 17

what are 3 arguments against artificial cloning in animals
6.2.1(d)

Answer 17

-many cloned embryos fail to develop
-clones often die early + have genetic abnormalities
-ethical issues associated with harvesting stem cells as it couldve developed into an embryo

Question 18

what is biotechnology
6.2.1(e)

Answer 18

use of biological molecules to produce useful products for human use

Question 19

how can you use bacteria to make food
6.2.1(e)

Answer 19

make cheese and yogurt

Question 20

how can you use yeast
6.2.1(e)

Answer 20

to make ethanol and make bread and
ethanol-alcoholic drinks

Question 21

what kind of metabolite is penicillin
6.2.1(e)

Answer 21

secondary metabolite-produced when the population has stopped growing
produced by fungi and bacteria

Question 22

how is insulin made
6.2.1(e)

Answer 22

genetically modified bacteria can be used to produce human insulin

Question 23

what are 4 advantages of using microorganisms for food production
6.2.1(f)

Answer 23

-reproduce quickly so high yields
-healthier high protein low cholesterol alternative
-grown using waste material which reduces cost
-grown in low temperature which reduces cost
no animal welfare issues so suitable for vegies

Question 24

what are 3 disadvantages of using microorganisms for food production
6.2.1(f)

Answer 24

-contamination causes food to spoil and causes health risks
-people don’t want to eat food made form waste materials
-food has little flavor so may not appeal to picky eaters

Question 25

what are the 4 substances you need for culturing microorganisms
6.2.1(g)

Answer 25

-nutrients
-oxygen
-optimum temperature
-optimum pH

Question 26

what are the 2 growth mediums you can use to culture microorganisms
6.2.1(g)

Answer 26

-broth-which is kept in jars
-agar-poured on a petri dish

Question 27

what are aseptic techniques
6.2.1(g)

Answer 27

techniques used to reduce the likely hood of contaminating the medium with unwanted bacteria or fungi

Question 28

name some aseptic techniques
6.2.1(g)

Answer 28

-washing hands/wearing gloves
-work near bunsen burner which creates a convection current to move microorganisms up in the air and away from working area
-keep lid on petri dish
-flame neck of bottles

Question 29

what is sterilisation
6.2.1(g)

Answer 29

the nutrient medium and equipment is heated in an autoclave

Question 30

what is inoculation
6.2.1(g)

Answer 30

the microorganisms are introduced onto a sterile medium by spreading

Question 31

what is incubation
6.2.1(g)

Answer 31

petri dishes are sealed with a small amount of tape

Question 32

what are two ways microorganisms can be grown at a large scale
6.2.1(g)

Answer 32

batch
continuous

Question 33

what is batch culture
6.2.1(g)

Answer 33

where microorganisms and a fixed volume of broth is added at the beginning to the vat. Time passes the microorganisms die and the products are collected

Question 34

what is continuous culture
6.2.1(g)

Answer 34

microorganisms and broth are both added at the beginning to the vat. The vat is continuously topped with respiratory substrate and products are continuously removed

Question 35

which metabolites are found in batch and continuous culture
6.2.1(g)

Answer 35

batch-secondary metabolites as they reach the death phase
continuous-primary metabolites as microorganisms are kept in the exponential phase

Question 36

what is a primary metabolite
6.2.1(g)

Answer 36

directly involved in growth and reproduction

Question 37

what is a secondary metabolite
6.2.1(g)

Answer 37

not directly involved in growth and reproduction

Question 38

describe the lag phase
6.2.1(h)

Answer 38

-popualtion doesnt grow quickly
-population is small and microorganisms are carrying out other activities
eg-transcription and translation, increasing cell size, taking up water

Question 39

describe the log (exponential) phase
6.2.1(h)

Answer 39

population doubles with each generation

Question 41

describe stationary phase
6.2.1(h)

Answer 41

-only reached in batch culture
-conc of respiratory substrates decrease
-conc of toxic metabolites increase
-birth rate=death rate and pop stops increasing

Question 42

describe death phase
6.2.1(h)

Answer 42

all organisms die because of accumulation of toxic metabolites and lack of respiratory substrates

Question 43

how can you immobalise an enzyme
6.2.1(i)

Answer 43

adding the enzyme to an insoluble material making it easier to collect

Question 44

what are 3 advantages of immobalising enzyme
6.2.1(I)

Answer 44

-enzymes are reusable which reduces cost
-easier to separate enzymes from products at the end of the reaction reducing costs
-increases temperature tolerance which allows a faster rate of reaction increasing yield

Question 45

what are 3 disadvantages of immobalising enzymes
6.2.1(i)

Answer 45

-immobalisation reduces the efficiency of enzymes by changig the tertiary structure of the active site or by adding a diffusion distance between enzymes and products
-higher short term costs as enzymes have to be produced before they can be used
-higher trained staff are required to carry out reactions with immobalised enzymes-these people cost money

Question 46

what are the 2 types of surface immobilisation
6.2.1(i)

Answer 46

enzymes are immobalised by adding they to clay
-adsorption
-covalent bonding

Question 47

describe adsorption
6.2.1(i)

Answer 47

enzymes are attached to surface by hydrophobic or ionic interactions

Question 48

2 disadvantages of adsorption
6.2.1(i)

Answer 48

-intercations with the surface are weak so enzymes may fall of and mix with the products
-interactions with the surface may affect the tertiary structure of the enzymes active site making it less efficient at binding to the substrate

Question 49

describe covalent enzymes
6.2.1(i)

Answer 49

covalent enzymes are covalently bonded to the surface

Question 50

1 advantage and 1 disadvantage of covalent enzymes
6.2.1(i)

Answer 50

(pos) enzymes are more strongly bonded to the surface so are less likely to become dislodged
-covalent bonds impacts on the enzymes tertiary structure of its active site

Question 51

what is entrapment and the 2 types
6.2.1(I)

Answer 51

enzymes are immobilised by trapping them in a jelly like structure
in a matrix
encapsulation

Question 52

in a matrix
6.2.1(i)

Answer 52

enzymes are embedded in a gelatin matrix

Question 53

advantage and disadvantage of a matrix
6.2.1(i)

Answer 53

-(pos) less impact on active site tertiary structure
-diffusion distance between reactants and enzymes so reaction rate decreases

Question 54

what is encapsulation
6.2.1(i)

Answer 54

enzymes are captured inside tiny capsules

Question 55

advantage and disadvantage of encapsulation
6.2.1(i)

Answer 55

-(pos) less impact on tertiary structure of active site
-diffusion distance between reactants and enzymes so diffusion distance decreases