cloning and biotechnology

Question 1

explain why plants are more able to form natural reproductive clones than animals.

Answer 1

1 (most) plant cells retain ability to differentiate /
totipotent ;
2 plants have , meristems / meristematic tissue ;
3 idea that plant cells can de-differentiate and then
differentiate into a different cell type;
4 (most) animal cells are , differentiated /
not totipotent / not pluripotent /
only able to differentiate into the
same type(s) of cell /
are multipotent;

Question 2

State one advantage and one disadvantage of using clones to test a treatment for a disease.

Answer 2

advantage
(genetically identical so) all react the same
or
genetic variable controlled ;
disadvantage
expensive (to produce)
or
don’t see varied response to drug like in real populations
(of mice)
or
idea that clones (of mice) may have unknown health issue
(which would affect responses) ;

Question 3

Outline two potential applications of adult cell cloning.

Answer 3

1 idea to produce , elite / best , animals ;
2 idea to save / preserve , endangered animals ;
3 grow / produce (spare) , stem cells / tissues / organs ;

Question 4

explain why ethanol is considered to be a primary metabolite of yeast.

Answer 4

ethanol is
produced in , all yeast growth phases / all of the time
or
production of ethanol increases as yeast population increases
or
idea that ethanol is a normal (metabolic waste) product
(of yeast) ;

Question 5

Ethanol is an important chemical that is manufactured on a large scale.One large-scale process to produce ethanol uses biotechnology, with yeast acting on sugar in a fermenter.Another large-scale process uses a chemical method instead of microorganisms. This method needs:
• ethene (obtained from oil)
• a high temperature of 300 °C
• high pressure steam.
Discuss the advantages and disadvantages of using yeast to make ethanol rather than using the chemical method.

Answer 5

advantages of using yeast
A1 less energy required ;
A2 does not need ,
high temperature / 300o
C / high pressure ;
A3 can use waste material (as a substrate) ;
A4 substrate is , sustainable / grown each year ;
A5 process does not use up , oil reserves / fossil fuels ;
A6 product is carbon neutral / no carbon footprint ;
A7 AVP ;
disadvantages of using yeast
D1 time consuming / takes several days ;
D2 needs , downstream processing / purification of product ;
D3 is killed by product ;
D4 can (only) use batch method ;
D5 aseptic / sterile , conditions required ;

Question 6

Suggest and explain how you might use the method of immobilised enzymes to obtain milk that was lactose-free.

Answer 6

reduce / slow, flow rate ;
repeat process / run milk through again ;
test for (named) sugars in milk ;

Question 7

Outline two methods of immobilising enzymes.

Answer 7

hydrophobic / ionic bond, to (named), solid / support ;
covalent bond / cross-link to, (named) substance;
membrane separation ;
(en)trap / encapsulate / suspend, in (named), matrix ;

Question 8

Enzyme immobilisation is used in the biotechnology industry for the large-scale production of materials.
Discuss the benefits of using immobilised enzymes for large-scale production.

Answer 8

(enzyme) can be re-used so reduces cost ;
product, pure(r) / uncontaminated ;
reduced downstream processing costs ;
(immobilised enzyme) works at high(er) temperature ;
(immobilised enzyme) works in changed pH ;
reaction, can be faster / have higher yield ,
because can be done at higher temperature ;

Question 9

State the biotechnological term for this type of vegetative propagation.

Answer 9

reproductive ;

cloning ;

Question 10

Name the modern technique which allows commercial growers to produce large numbers of genetically identical plants that are also virus-free.

Answer 10

(callus / plant) tissue culture / micropropagation ;

Question 11

Explain what is meant by a primary metabolite.

Answer 11

(molecule made in or needed for cell’s normal)
survival / function / growth / development / reproduction ;
named example ;

Question 12

Suggest two ways in which named factors inside the fermenter could be adjusted in order to maximise the yield of HGH.

Answer 12

factor (F) change needed (C)
oxygen ; increase it / more / high or
stir / sparging ;
(named)
nutrient ;
increase it / more / high
or
stir ;
temperature ;
maintain at / control at /
 change to , optimum
or
cool
or
ref. to using water jacket ;
pH ;
maintain at / control at /
 change to, optimum
or
add, buffer / acid / alkali ;
(waste)
product / gas /
CO2 ;
harvest / remove /
 waste gas vent ;
other /
unwanted /
harmful /
competing ,
 microbes ;
prevent entry / asepsis ;

Question 13

State two methods of immobilising an enzyme.

Answer 13

entrapment / alginate beads / cellulose network ;
adsorption / carrier bound
or
stuck to , porous carbon / clay / resin / glass ;
covalent bonding
or
cross-linking enzymes to each other and to clay (using
glutaraldehyde) ;
membrane separation
or
enzyme and substrate either side of partially permeable
membrane ;

Question 14

Outline the process by which an animal, such as the first transgenic goat, may be cloned to produce a population.

Answer 14

somatic / adult, cell / nucleus ;
fused with / injected into ;
empty / enucleate , egg cell ;
from another goat ;
idea of electric shock / electrostimulation ;
this cell or embryo, grown on , in vitro / in tied oviduct ;
(early) embryo / blastocyst , split ;
idea that embryos replaced in , surrogate mothers /
other females ;

Question 15

Discuss the advantages and disadvantages of cloning the transgenic goat compared with breeding the transgenic goat with normal goats.

Answer 15

advantages
all offspring will inherit the, (silk) gene / foreign DNA ;
all offspring female ;
certain / all make , silk / milk / product ;
faster / many obtained in a short time ;
avoid mating risks ;
max 3 advantages
disadvantages
no genetic variability (in population) / AW ;
(so makes goats) more susceptible to, environmental
factors / (infectious) disease ;
cloned animals may, have shorter life spans / be less
healthy ;
idea that cloning success rate is very poor ;
(more) expensive / needs (more) technology / (more)
labour intensive ;

Question 16

Describe one distinctive feature of the cell structure of each of these microorganisms.
fungal cell
bacterial cell

Answer 16

fungal
long cells / hyphae
 OR
multinucleate
 OR
chitin cell wall ;
bacterial
free DNA / DNA not in a nucleus
 OR
circular DNA (molecule)
 OR
naked DNA / no histones
 OR
peptidoglycan / murein, cell wall
 OR
smaller / 70S / 18nm, ribosomes ;

Question 17

State what is meant by biotechnology using suitable examples from different areas of biotechnology and explain why microorganisms are used in biotechnological processes.
In your answer you should give examples of products and the microorganisms used to make them, as well as the advantages of using microorganisms.

Answer 17

What is biotechnology?
large-scale / industrial / commercial use (of living
organisms / enzymes) ;
to produce , food / named example ;
detail of , microbe / enzyme , involved ;
to produce , drugs / named example ;
detail of , microbe / enzyme , involved ;
to make , (useful) enzymes / biogas / calcium citrate /
for bioremediation / for water treatment / for microbial
mining ;
Advantages of microorganisms
fast, growth / reproduction / products ;
microbes can be genetically engineered ;
processes occur at low , temperatures / pressures ;
low , temp / pressure , cheaper / safer , to maintain ;
products , pure / easy to separate ;
grow on unwanted, food / nutrients ;
AVP ;

Question 18

State the name given to the process in which plants reproduce asexually by means such as suckers.

Answer 18

vegetative propagation ;

Question 19

Many ornamental plants for gardens can be cloned by tissue culture.
Describe the process of cloning plants by tissue culture.
In your answer you should make clear the order in which the steps of the process occur.

Answer 19

cut plant material into , explants / small pieces ;
example of part of plant used e.g. leaf / stem / root /
bud / meristem / dividing region at tip of plant ;
sterilise explant ;
(with) bleach / sodium hypochlorite / alcohol ;
place on , agar / growth medium ;
containing , glucose / amino acids / nitrates / phosphates ;
callus
or mass of , undifferentiated / totipotent , cells ;
high auxin and cytokinin (for callus formation) ;
subdivide callus / sub-culturing ;
treat to induce , roots / shoots ;
change plant hormone ratio ;
transfer to , greenhouse / soil /
less controlled environment / non-sterile environment ;
ref. aseptic conditions (anywhere within stages 5-11) ;

Question 20

List two advantages and two disadvantages of cloning plants by tissue culture.

Answer 20

advantages
1 quick ;
2 disease-free / virus-free , stock created ;
3 plants have same feature / uniform plants created ;
4 can reproduce infertile plants ;
5 can reproduce plants that are hard to grow from seed ;
6 create whole plants from GM cells ;
7 production , not determined by seasons /
at any time / anywhere in the world ;
8 (plantlets small) can be transported easily /
grown in small space ;
9 can save rare species from extinction ;
disadvantages
10 expensive / labour intensive , process ;
11 process can fail due to microbial contamination ;
12 all offspring susceptible to same ,
pest / disease /
named environmental factor (e.g. drought) ;
13 no / low / little , genetic variation ;

Question 21

Name two modern techniques or procedures that can be used in the selective breeding of dairy cows.

Answer 21

artificial insemination / AI ;
in vitro fertilisation / IVF ;
idea of progeny testing ;
embryo transplantation / use of surrogate mother ;
cloning ;
genetic screening / use of gene probes ;

Question 22

Suggest why yogurt is a suitable food for lactose-intolerant people.

Answer 22

lactose has been ,
removed / digested / respired /
broken down (by bacteria) ;
to , lactic acid / lactate / other sugars ;
yogurt still a good source of , calcium / vitamins ;

Question 23

What evidence is there that penicillin is a secondary metabolite?

Answer 23

idea that most penicillin produced after main growth phase ;
after 24 h / when nutrients declining ;
not needed for growth ;
(however evidence not entirely clear as)
production begins during biomass log phase ;

Question 24

) Explain the importance of maintaining aseptic conditions in manufacturing penicillin by fermentation.

Answer 24

to avoid unwanted microbe , entry / presence ;
so no competition for nutrients ;
so conditions remain unchanged ;
so no decrease in yield ;
so no contamination of , batch / product / penicillin
or
batch is unusable ;
to prevent escape of ,
microbes / fungus / Penicillium / spores ;

Question 25

State three physical or chemical factors within the fermenter, other than nutrient levels, that need to be monitored and controlled.For each factor, explain why it must be controlled.

Answer 25

temperature - as it affects enzymes ;
pH - as it affects enzymes ;
oxygen content – ref. respiration ;

Question 26

one group of research scientists at a hospital wanted to sequence a disease-causing
●mutation to learn more about a human disease; these scientists started their research using white blood cells;another group of scientists at a biotechnology company wanted to clone the insulin gene
●in order to manufacture its protein product to treat diabetes; these scientists started their research using cells from the pancreas.Suggest and explain the biological reasons why the two groups each started with a different cell.

Answer 26

hospital
WBCs , easy to obtain / obtained from blood sample ;
WBCs good source of DNA ;
mutant gene’s location unknown /
 need to look in whole genome ;
biotechnology company
idea that insulin made in pancreas ;
many mRNA copies there / mRNA easier to find ;

Question 27

Compare in vitro(PCR)/vivo gene cloning by explaining the advantages of each.

Answer 27

advantages of PCR
PCR quicker ;
explanation ;
PCR uses less equipment ;
explanation ;
PCR uses less space ;
explanation ;
PCR less labour-intensive / easier /
 (some parts of process) less costly ;
explanation ;
PCR combines selection of gene and amplification but
 in vivo requires separate steps ;
PCR safer ;
explanation ;
PCR can use lower quality DNA ;
explanation ;
advantages of in vivo
in vivo less prone to mutation ;
explanation ;
in vivo less expensive ;
explanation ;
in vivo less technically complex ;
explanation ;
in vivo useful , when gene less well known /
 as longer piece of DNA can be cloned ;

Question 28

Explain why making cheese can be described as a biotechnological process.

Answer 28

microbes /
 (living) organisms /
 cells /
 enzymes ;
(make) product /
 for human benefit /
 (carry out) conversion / reaction / industrial process ;

Question 29

Suggest two benefits of the pasteurisation stage.

Answer 29

microbes / AW , killed / removed / not present ;
enzymes denature
d ;
(so no) competitors /
 unwanted reactions /
 (human) health risk ;

Question 30

Rennin could, in theory, be immobilised for use in cheese-making.List two potential advantages of this.

Answer 30

enzyme can be removed to be) used again ;
(enzyme can) to leave pure(r) product ; ora
(enzyme) more stable / more efficient / works better ;

Question 31

Rennin can now be made by genetically modified microorganisms. Outline the process by which bacteria can be genetically modified to produce rennin.

Answer 31

Section I - Obtaining the gene
use restriction, enzyme / endonuclease ;
to, cut out / get / isolate, (rennin) gene / DNA coding for rennin
or to, fragment / digest, DNA ;
gene probe ;
OR
obtain rennin mRNA ;
(use) reverse transcriptase ;
to make cDNA ;
OR
sequence, rennin (protein) ;
work out base code ;
make this DNA sequence ;
sticky ends ;
Section II - Vector
cut (open), plasmid / phage ;
using same restriction enzyme ;
annealing / base pairing of sticky ends ;
join sugar-phosphate backbones ;
(using DNA) ligase ;
recombinant, vector / plasmid / phage / DNA ;
Section III - Introduction into host cell
mix with bacteria ;
detail of conditions ;
transformation (plasmid) / transduction (phage) ;