GCSE Biology –
Uses of Biologica
Resources
Pearson Edexcel IGCSE
, BIOLOGY GCSE – USE OF BIOLOGICA
Contents
q Selective Breeding –
q Improving Crop Yields –
q Glasshouses & Polytunnels –
q Fertilisers, Pests, Monoculture & Crop Rotation –
q Modified Nitrogen Cycle –
q Controlling a Fish Farm –
q Advantages & Disadvantages of a Fish Farm –
q Yeast –
q Industrial Fermenter –
q Fermenting Bacteria for Milk & Yoghurt –
q Genetic Engineering –
q Genetic Engineering to make Insulin –
q Genetically modifying plants –
q Genetically Modifying Animals –
q Cloning Plants –
q Cloning Animals –
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, BIOLOGY GCSE – USE OF BIOLOGICA
Selective Breeding It's sometim
‘artificial s
Selective Breeding – The selection and breeding of only the individuals with desired human ch
characteristics the enviro
o This process doesn’t stop here but then from the offspring the two with desired
characteristics are bred and this must be repeated for many successful generations to say you
a ‘new breed’ that will reliably show those selected characteristics in all offspring as over each
generation the desired trait gets stronger
Why do we selectively breed? Selective Breeding in Animals:
à Higher yields of meat/milk/grain [A+P] q Farmer use ‘artificial insemination’
à Resistant to pests [A+P] q Bulls with desired features are kept and the seme
à Resistant to diseases [A+P] obtained from them. It’s then diluted, frozen and
à Hardier(to survive in harsh climates) [P] q Quicker, cheaper & safer to only transport semen
à Better balance of nutrients [P] q Farmers buy this semen to inseminate into their ow
à Attractiveness/flowers/smell [P] q Artificial insemination is good because it means 1
à Speed/fertility/good mothering [A] fertilise thousands of cows, even if it was dead
Problems with Selective Breeding: Selective Breeding in Plants:
o Inbreeding (occurs when your two best Selective breeding can also be used to combine t
are related to each other [A+P]) different desirable characteristics such as a tall wh
o Results in reduction of the gene pool which has good grain and is easily damaged and
meaning less alleles in a population and wheat plant which has bad grain but can resists th
so > chance of organisms getting new These are cross-bread and the best results are then
diseases and inheriting genetic defects again resulting in a new variety combining the goo