Use of Biological Resources Flashcards
give the 4 advantages of glasshouses
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
why plants sometimes need fertilisers
plants need certain elements… nitrogen, potassium and phosphorus
sometimes these are missing from soil so fertilisers provide them and increase crop yield
what is the problem with pesticides ?
also poisonous to humans so must be kept at a safe level
they also harm other wildlife
Explain what Biological control is
using other organisms to reduce numbers of pests by encouraging or adding organisms
examples : predators, parasites or disease-causing
Explain the advantages/disadvantages of Biological control
longer-lasting effect than pesticide
less harmful to wildlife/humans
introducing new organisms is a risk
Describe the process of yogurt (6 steps)
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
what is pasteurisation ?
process of killing microbes in food and drink
what is an industry fermenter ?
where microorganisms are grown
full of liquid ‘culture medium’ in which microorganism grow and reproduce
how are nutrients provided in fermenters?
provided in the liquid culture medium
describe the pH in fermenters
monitored and kept at optimum level for the microorganism’s enzymes to work efficiently
describe the temp in fermenters
monitored and kept at optimum level (for enzymes)
water-cooler jacket makes sure doesn’t get too hot so enzymes don’t denature
what are the paddles for in fermenters?
stir the medium so it can circulate and kept fresh, which means microorganisms can always access nutrients for growth
what if microorganisms need oxygen in fermenters?
sterile air is pumped in, allowing microorganisms to respire
what happens to the vessels in fermenters?
sterilised between uses with super heated steam that kills unwanted microbes
why is it important to keep fermenters aseptic ?
so microorganisms aren’t competing with other organisms
and so product doesn’t get contaminated
describe the process of making beer (6 steps)
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)
give the process of selective breeding
Farmer/Human selects ORGANISM with DESIRED CHARACTERISTIC and breed with OTHER SEX. This can be repeated over several generations.
how the water quality is maintained (fish farming)?
stir water
monitor and add O²
remove dead algae/food/waste
what is inter specific predatation ?
compete with other species
what is intraspecific predatation?
compete with own species
how is inter/intraspecific predatation controlled (fish farming) ?
make sure well fed
segregate species/size/gender
ensure strong and over top netting
don’t overcrowd
how to control disease (fish farming)?
remove dead/ill fish
give antibiotics/fungicides
don’t overcrowd
how to ensure fish well fed (fish farming) ?
feed few times a day
high protein food
what is recombinant DNA
when 2 different bits of DNA stuck together
what is a vector (genetic engineering)
plasmid or virus used to transport a gene from organisms
explain the process of genetic engineering (7 steps)
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
problems with growing genetically modified crops
transplanted genes may get into environment, for example weeds could become herbicide resistant
they may also affect food chains or human health
describe the process of micro propagation
cells taken from parent plant
cells grow in nutrient agar
planted when big enough
creates 1000s plants (clones)
what is transgenic
organism that has genes transferred from another species
explain the process of animal cloning (5 steps)
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
pros of cloning
faster than selective breeding
guarantees desired characteristic
infertile animals can be cloned
cons of cloning
expensive, time-consuming and difficult
unethical
no genetic variation so if all catch/develop disease they all die
