Patterns of inheritance Flashcards
1
Q
allele
A
- one or more alternative versions of the same gene
2
Q
genotype
A
- alleles an organism has
3
Q
dominant
A
- characteristics appear in the phenotype even when there is only one copy
- e.g DD or Dd
4
Q
linkage
A
- the genes that are on the same chromosome
5
Q
codominant
A
allele whose characteristic appear together with another allele in the population
- blood type
6
Q
recessive
A
- characteristic only appears in the phenotype if there is 2 copies present
7
Q
phenotype
A
- characteristics an organisms alleles produce
8
Q
allopatric speciation
A
- geographical isolation = physical barrier
- experience different conditions and develop into different characteristics (change in allele frequency)
- eventually individuals would have changed so much that they cant produce fertile offspring (form separate species)
9
Q
sympatric speciation
A
- random mutation occurs within a population resulting in reproductive isolation
- more common in plants than animals
- forms a sterile species ( cant undergo mitosis
10
Q
founder effect
A
- when just a few organisms from a population start a new population
- there are only a small number of different alleles in initial pool
- smaller populations are more likely to become extinct due to new disease as little genetic variability
11
Q
stabilising selection
A
-when the environment stays the same
- the same alleles are likely to be selected
- little change in the characteristic of the population
- allele frequency remains the same
12
Q
natural selection
A
- always genetic variation from mutation
- selection pressure
- members of a population have the selective advantage
- therefore survive, reproduce and pass on advantageous alleles
- increasing allele frequency
- leading to evolution
13
Q
genetic drift
A
- change in allele frequency due to chance
- has large effect on a smaller population
14
Q
genetic bottle neck
A
- reduction in population size
- many alleles are lost
- reduction in gene pool
15
Q
reproductive isolation
A
- seasonal = different mating season
- behavioral = develop different courtship rituals (not attractive to main population)
- mechanical changes = changes in genitalia (reduces successful mating)
