9: Genetic Diversity and Adaptation Flashcards
Mutation
Any change to the quantity or the base sequence of the DNA of an organism
Gene mutation
Any change to one or more nucleotide bases, or change in the sequence of bases in DNA
Chromosome mutation
Changes in the structure or number of whole chromosomes
Non-disjunction
When individual homologous pairs fail to separate during meiosis
Meiosis
The division of a cell that produces four daughter cells, each with half the number of chromosomes as the parent cell
Independent segregation
The random lining up of the pairs of chromosomes, the combination of chromosomes in a random order, a matter of chance
Crossing over
When the chromatids cross over one another many times
Recombination
When broken-off portions of chromatid recombine with another chromatid
Species
A group of similar organisms that can breed together to produce fertile offspring
Genetic diversity
The total number of different alleles in a population
Allele frequency
The relative frequency of an allele at a particular locus in a population
Gene pool
The total number of alleles in a particular population at a specific time
Directional selection
Selection may favour individuals that vary from the mean of the population
Stabilising selection
Selection may favour average individuals, preserving characteristics of the population
Anatomical
Characteristics relating to bodily structure
