Use of Biological Resources

Question 1

give the 4 advantages of glasshouses

Answer 1

keeping enclosed makes it easier to keep them pest/disease free
supply artificial light when sun goes down
traps sun heat or can use heater in the winter
can increase CO² levels by burning paraffin

Question 2

why plants sometimes need fertilisers

Answer 2

plants need certain elements… nitrogen, potassium and phosphorus
sometimes these are missing from soil so fertilisers provide them and increase crop yield

Question 3

what is the problem with pesticides ?

Answer 3

also poisonous to humans so must be kept at a safe level

they also harm other wildlife

Question 4

Explain what Biological control is

Answer 4

using other organisms to reduce numbers of pests by encouraging or adding organisms
examples : predators, parasites or disease-causing

Question 5

Explain the advantages/disadvantages of Biological control

Answer 5

longer-lasting effect than pesticide
less harmful to wildlife/humans
introducing new organisms is a risk

Question 6

Describe the process of yogurt (6 steps)

Answer 6

1) sterilise equipment
2) pasteurise milk, then cool
3) add lactobacillus bacteria and leave to be incubated in a fermenter
4) bacteria ferment lactose sugar in milk to form lactic acid
5) lactic acid causes milk to clot and solidify
6) flavours/colours added and yogurt packaged

Question 7

what is pasteurisation ?

Answer 7

process of killing microbes in food and drink

Question 8

what is an industry fermenter ?

Answer 8

where microorganisms are grown

full of liquid ‘culture medium’ in which microorganism grow and reproduce

Question 9

how are nutrients provided in fermenters?

Answer 9

provided in the liquid culture medium

Question 10

describe the pH in fermenters

Answer 10

monitored and kept at optimum level for the microorganism’s enzymes to work efficiently

Question 11

describe the temp in fermenters

Answer 11

monitored and kept at optimum level (for enzymes)

water-cooler jacket makes sure doesn’t get too hot so enzymes don’t denature

Question 12

what are the paddles for in fermenters?

Answer 12

stir the medium so it can circulate and kept fresh, which means microorganisms can always access nutrients for growth

Question 13

what if microorganisms need oxygen in fermenters?

Answer 13

sterile air is pumped in, allowing microorganisms to respire

Question 14

what happens to the vessels in fermenters?

Answer 14

sterilised between uses with super heated steam that kills unwanted microbes

Question 15

why is it important to keep fermenters aseptic ?

Answer 15

so microorganisms aren’t competing with other organisms

and so product doesn’t get contaminated

Question 16

describe the process of making beer (6 steps)

Answer 16

1)barley seeds germinated, during which amylase breaks down starch into sugars
2)seeds dried to make malt
3)malt mashed up and water added
4)hops added for flavour
5)yeast added and mixture incubated
6)yeast ferments sugar into alcohol
(alcohol eventually kills off yeast)

Question 17

give the process of selective breeding

Answer 17

Farmer/Human selects ORGANISM with DESIRED CHARACTERISTIC and breed with OTHER SEX. This can be repeated over several generations.

Question 18

how the water quality is maintained (fish farming)?

Answer 18

stir water
monitor and add O²
remove dead algae/food/waste

Question 19

what is inter specific predatation ?

Answer 19

compete with other species

Question 20

what is intraspecific predatation?

Answer 20

compete with own species

Question 21

how is inter/intraspecific predatation controlled (fish farming) ?

Answer 21

make sure well fed
segregate species/size/gender
ensure strong and over top netting
don’t overcrowd

Question 22

how to control disease (fish farming)?

Answer 22

remove dead/ill fish
give antibiotics/fungicides
don’t overcrowd

Question 23

how to ensure fish well fed (fish farming) ?

Answer 23

feed few times a day

high protein food

Question 24

what is recombinant DNA

Answer 24

when 2 different bits of DNA stuck together

Question 25

what is a vector (genetic engineering)

Answer 25

plasmid or virus used to transport a gene from organisms

Question 26

explain the process of genetic engineering (7 steps)

Answer 26

1) select desired human gene
2) remove plasmid from bacteria cell
3) cut out human gene using restriction enzyme
4) cut open plasmid using same restriction enzyme
5) gene stuck into plasmid using ligase
6) recombinant plasmid inserted into bacteria
7) bacteria goes into fermenter where it reproduces and produces desired gene

Question 27

problems with growing genetically modified crops

Answer 27

transplanted genes may get into environment, for example weeds could become herbicide resistant
they may also affect food chains or human health

Question 28

describe the process of micro propagation

Answer 28

cells taken from parent plant
cells grow in nutrient agar
planted when big enough
creates 1000s plants (clones)

Question 29

what is transgenic

Answer 29

organism that has genes transferred from another species

Question 30

explain the process of animal cloning (5 steps)

Answer 30

1) cell taken from animal with desired characteristic
2) egg cell removed from another animal and nucleus removed
3) body cell nucleus put into enucleated egg cell and fuses
4) division stimulated with electric impulse
5) dividing embryo implanted into surrogate

Question 31

pros of cloning

Answer 31

faster than selective breeding
guarantees desired characteristic
infertile animals can be cloned

Question 32

cons of cloning

Answer 32

expensive, time-consuming and difficult
unethical
no genetic variation so if all catch/develop disease they all die