CB4D Breeds and varieties Flashcards
What is selective breeding
The process by which humans artificially select organism with desirable characteristics and breed them to produce offspring with similar phenotypes
Outline the main steps involved in selective breeding
1) Identify a characteristics e.g disease resistance
2) Select parent organisms that show the desired traits and breed them together
3) Select offspring with the desired traits and breed them together
4) Process repeated until all offspring have the desired traits
What is the main advantage of selective breeding
Creates organisms with desirable features
Crops produce a higher yield of grain
Cows produce a greater supply of milk
Plants produce larger fruit
Domesticated animals
Other than in agriculture where else is selective breeding useful
In medical search
In sports e.g horse racing
What are the disadvantages of selective breeding (4)
Reduction in the gene pool
Inbreeding results in genetic disorders
Development of other physical problems e.g respiratory problems to bulldogs
Potential to unknowingly select harmful recessive alleles
What is genetic engineering
The modification of the genome of an organism by the insertion of a desired gene from another organism
Enables the formation of an organism with beneficial characteristics
Describe the benefits of genetic engineering (3)
Increased crop yields for growing population
Useful in medicine
Gm crops produce scarce resources
Describe the risks of genetic engineering (4)
Long term effects of consumption of GM crops unknown
Negative environmental impacts e.g reduction in biodiversity
Late-onset health problems in GM animals
GM seeds are expensive
