8. Changes in genetic makeup Flashcards
An allele is ?
a variation of a gene at a particular gene locus
A species is defined as …
A group of organisms that interbreed to produce viable and fertile offspring
Phenotype is the ?
physical, behavioural or physiological characteristic of an organism which are a result of the combination of genotype and the environment
Allele frequency is ..
The proportion of one allele in a population
A point mutation is when ?
one single nucleotide is changed
A silent mutation is where the ?
DNA base has changed but this will still code for the same of amino acid because the code is degenerate.
A missense mutation is where ?
DNA base has changed and this changes the amino acid coded for. The sequence of amino acids is different and therefore changes the tertiary structure of the protein and it will no longer function correctly.
STOP that nonsense
A nonsense mutation is where ?
DNA base has changed and this changes the amino acid coded for as it codes for a stop codon instead. The sequence of amino acids is then shorter and therefore changes the tertiary structure of the protein and it will no longer function correctly.
A population is defined as ?
a group of individuals of the same species in the same defined geographical area
Evolution is the ?
change in allele frequency over time
Define gene flow
The movement of individuals into or out of of a population changing allele frequency
Genetic drift is the ?
change in allele frequencies in a population by chance
Founder effect is when ?
A group of individuals, whose allele frequency unrepresentative of the normal population, breakawayand found a new population
Bottleneck effect is ?
A severe reduction in genetic diversity due to a catastrophe that may change allele frequency
Extinction is defined as ?
When no member of a particular species exists