BIOL 105: Evolution Midterm
2 with 100% correct answers
(graded A+)
Microevolution - answer - evolutionary change within a species
- genetic change over successive generations
- driven by population level processes
Phenotype - answer - measurable traits
- variation may or may not be heritable
Three main types of variation - answer - Discrete (Mendelian) variation
- Continuous variation
- Phenotypic plasticity
**Only the first two are heritable
Discrete (Mendelian) variation - answer - qualitative traits
- one or a few genes underlying variation
- ex. cyanogenesis of white clover
- 2 genes Ac and Li
- Ac/ac: presence/absence of cyanogenic glucosides
Li/li: presence/absence of hydrolyzing enzyme
Continuous variation - answer - quantitative traits
- polygenic (many genes underlying variation)
- ex. human height, disease risk
, - typically polygenic; potentially complex genotype by environment
interactions
Phenotypic plasticity - answer - variation caused by the environments
- no generic basis for variation
3 ways to determine if a trait has a genetic basiss - answer 1. segregation of
trait variation in crosses
2. Parent-offspring correlations
3. Common garden experiments
Maternal effect - answer non-genetic effect of a mother on offspring's
phenotype; reflects environment offspring were exposed to during
gestation/rearing
Mendelian inheritance - answer - Mendel's work was revolutionary
- satisfies one prerequisite for evolution via selection: heritability of variation
Mendel's laws - answer - Law of segregation
- Law of independent assortment
Law of segregation - answer - each individual has two gene copies at a locus,
which segregate randomly during gamete production
law of independent assortment - answer - which allele is passed down to the
next generation at one locus is independent of which allele is passed down at
another locus
Transmission genetics - answer - the mechanism by which genes are passed
from parents to offspring
2 with 100% correct answers
(graded A+)
Microevolution - answer - evolutionary change within a species
- genetic change over successive generations
- driven by population level processes
Phenotype - answer - measurable traits
- variation may or may not be heritable
Three main types of variation - answer - Discrete (Mendelian) variation
- Continuous variation
- Phenotypic plasticity
**Only the first two are heritable
Discrete (Mendelian) variation - answer - qualitative traits
- one or a few genes underlying variation
- ex. cyanogenesis of white clover
- 2 genes Ac and Li
- Ac/ac: presence/absence of cyanogenic glucosides
Li/li: presence/absence of hydrolyzing enzyme
Continuous variation - answer - quantitative traits
- polygenic (many genes underlying variation)
- ex. human height, disease risk
, - typically polygenic; potentially complex genotype by environment
interactions
Phenotypic plasticity - answer - variation caused by the environments
- no generic basis for variation
3 ways to determine if a trait has a genetic basiss - answer 1. segregation of
trait variation in crosses
2. Parent-offspring correlations
3. Common garden experiments
Maternal effect - answer non-genetic effect of a mother on offspring's
phenotype; reflects environment offspring were exposed to during
gestation/rearing
Mendelian inheritance - answer - Mendel's work was revolutionary
- satisfies one prerequisite for evolution via selection: heritability of variation
Mendel's laws - answer - Law of segregation
- Law of independent assortment
Law of segregation - answer - each individual has two gene copies at a locus,
which segregate randomly during gamete production
law of independent assortment - answer - which allele is passed down to the
next generation at one locus is independent of which allele is passed down at
another locus
Transmission genetics - answer - the mechanism by which genes are passed
from parents to offspring
