B14- Variation Flashcards
What is variation?
Differences in the characteristics of individuals in a population
What can cause variation?
Genetic and environmental causes (or both)
How do new phenotype variants occur?
Mutations
What are the effects of mutations?
Most have no effect on the phenotype, some influence phenotype and very few lead to a new phenotype
What is selective breeding?
Breeding plants and animals for a particular characteristic
What is the process of selective breeding?
1- Choose parents with desired characteristics
2- breed them together
3- choose offspring with the desired characteristics and breed them
4- continue over many generations
What are the consequences of selective breeding
Inherited defects and diseases - (inbreeding)
Reduced variation- susceptible to disease
What is genetic engineering?
Modifying the genome of an organism by introducing the gene of another organism for a desired characteristic
Why have plant crops been genetically engineered?
Resistance to disease and pesticides, produce bigger fruits and higher yields
What are concerns about genetically engineered crops
Effects on wildflowers and ecosystems and impacts on human health not fully understood
How have bacteria been genetically engineered
To produce useful substances like human insulin
What are enzymes used for in genetic engineering
To cut out the required gene
What is used to transfer the required gene into the new cell for genetic engineering
A vector such as a bacterial plasmid or virus
What are the benefits of genetic engineering?
Treatment of inherited human diseases, lead to higher value of crops due to bigger yields, crops better adapted to their environment
Risks of genetic engineering
Genes may spread which will destroy ecosystems, negative impacts on wildflowers and insects, ethical concerns about future uses, long term effects not fully evaluated
