Term
|
Definition
| When 1 locus affects 2 or more traits |
|
|
Term
|
Definition
| Alleles at 1 locus affect expression of alleles at a different locus |
|
|
Term
|
Definition
| 2 or more loci on same chromosomes |
|
|
Term
| Alleles Frequencies (P, Q, H, p, q, h) |
|
Definition
P=AA Q=aa H=Aa
p=A q=a p=-q
P+H+Q=1 |
|
|
Term
| Hardy-Weinberg Equilibrium |
|
Definition
p^2 + 2pq + q^2 = 1
- large, randomly mating population
- no mutation, migration, or selection
- only for autosomes |
|
|
Term
|
Definition
Females are ZW or Z
Males are ZZ |
|
|
Term
|
Definition
| Phenotypes only observed in one sex |
|
|
Term
|
Definition
| Heterozygotes have different phenotypes depending on sex |
|
|
Term
|
Definition
| Only expressed if they come from one parent or another |
|
|
Term
| On which factors does the proportion of alleles in a new population depend? |
|
Definition
- immigration rate
- difference in allele frequencies between the two populations |
|
|
Term
| True or false: changes in allele frequency changes genotype |
|
Definition
|
|
Term
| What factors affect changes in allele frequency/genotype? Which one only has observable effects after a long period of time? |
|
Definition
Migration, selection, and mutation
Mutation is long-term |
|
|
Term
|
Definition
| Movement of alleles from one population to another |
|
|
Term
| In the migration equation, what are m, p1, p2, and p1'? |
|
Definition
m = percentage of new population that make up of total population
p1 = frequency of A in 1st population
p2 = frequency of A in 2nd population
p1' = frequency of A in a new combined population |
|
|
Term
|
Definition
| Determines which individuals become the parents of the next generation |
|
|
Term
| What are the types of selection? |
|
Definition
|
|
Term
| In natural selection, what must an individual/population do to survive? |
|
Definition
|
|
Term
| What pressures are associated with evolution, extinction, and bottlenecks? (massive/moderate/subtle) |
|
Definition
Evolution = subtle
Bottlenecks = moderate
Extinction = massive |
|
|
Term
| What is artificial selection? |
|
Definition
| When humans decide the parents of future offspring (chosen for appearance, function, productivity) |
|
|
Term
| True or False: Fitness is an aspect of genotype |
|
Definition
| False, it is an aspect of phenotype |
|
|
Term
| Most mutants are _____ to wild type, but if heterozygote's fitness is _____ or _______ than the wildtype, the mutation can stay. |
|
Definition
recessive
equal to
greater |
|
|
Term
| What are the variables in the allele frequency/selection formulae, and what do they imply? |
|
Definition
po = freq of origingal allele (before selection)
qo = freq of mutated (recessive) allele (before selection) ... 1 - po
S1 = proportion of heterozygotes that can't reproduce (1-fitness 2poqo)
S2 = proportion of homozygous recessive that can't reproduce (1-fitness 2qo^2)
p1 = dominant (original) allele frequency after selection |
|
|
Term
|
Definition
| ... are controlled by 1 or a few loci |
|
|
Term
|
Definition
| ... are controlled by multiple loci (polygenic traits) - continuous phenotypes - range measured as variation |
|
|
Term
| Threshold traits are also called _______ traits, and are q_____itative, and ______ |
|
Definition
meristic
quantitative
polygenic |
|
|
Term
|
Definition
|
|
Term
|
Definition
How much variability there is within a population of a certain trait
- "the average squared difference from the mean" |
|
|
Term
| How can variability (P) be partitioned? |
|
Definition
P = G + E and G = A + D + I, therefore
P = A + D + I + E
Where A is additive (alleles contribute to phenotype)
D is dominance (loci expressing dominance in heterozygotes)
I is the epistatic interactions between loci
E is the environment |
|
|
Term
| True or False: The EFFECTS of Additive, Dominance, and Epistatic variances are all passed on, along with the alleles. |
|
Definition
| False, all the alleles are passed on (obvi) but the effects are only passed on from additive variance |
|
|
Term
|
Definition
|
|
Term
|
Definition
Strong parental genetic influence = high heritability (weak = low)
- ranges from 0-1 but is rarely more than 0.50 |
|
|
Term
| If the heritability is b/w 0.35 and 0.5 it has: |
|
Definition
|
|
Term
| If the heritability is b/w 0.35 and 0.15 it has: |
|
Definition
|
|
Term
| If the heritability is less than 0.15 it has: |
|
Definition
|
|
Term
|
Definition
| Reaction to stimuli, external or internal, that alters an organism's response to it's environment |
|
|
Term
| What two factors influence behaviour patterns? |
|
Definition
Genetic and Environmental
- also, the nervous system plays an important role |
|
|
Term
| What is the behaviour-first method? |
|
Definition
- specific behaviour is identified, genetic crosses are used to produce strains that breed true
- once strains are established, further crosses identify and analyze genetic components of the behaviour
e.g. aggresion and anxiety in mice - identified a locus on chromosome 1 |
|
|
Term
| What is the gene-first method? |
|
Definition
- mutagenesis followed by screening to identify single-gene mutations associated with abnormal behaviour
e.g. geotaxis in Dresophila |
|
|
Term
|
Definition
Movement toward or away from gravity
+ve: up
-ve: down |
|
|
Term
| True or False: Selection is weaker for -ve geotaxis, and is genetically controlled and polygenic |
|
Definition
| Selection is stronger for -ve geotaxis, and is genetically controlled and polygenic |
|
|
Term
|
Definition
| They can use a single experiment to identify changes in 100s-1000s of genes that influence complex traits |
|
|
Term
| Explain sodium-potassium pumps in Dresophila |
|
Definition
The dendrite end of neurons generates electrical impulses which travel to other end (axon) and are transmitted to adjacent neuron
- transport of Na+/K+ ions across plasma membrane to propagate the impulse |
|
|
Term
| What gene encodes the Na+ channel protein? |
|
Definition
|
|
Term
| What gene encodes the K+ channel protein? |
|
Definition
|
|
Term
| What was/were used to study progression and treatment of Huntington's Disease in humans? |
|
Definition
|
|
Term
|
Definition
| - have antagonistic (negative) effects |
|
|
Term
|
Definition
| group of individuals with a common set of genes, in the same geographic area, actively or potentially interbreeds |
|
|
Term
|
Definition
| all alleles present in a population (most populations have a high degree of heterozygosity) |
|
|
Term
| How can genetic variation be detected in a population be detected? (two ways) |
|
Definition
Using artificial selection
Compare nucleotide sequences of genes carried by individuals in a population |
|
|
Term
| If variation exists in a population, what will happen to the phenotype? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| True or False: Variation in genome sequence always has an effect on phenotype |
|
Definition
| False, some differences between genome sequences have no effect on phenotype (like a change in nucleotides that codes for the same amino acid) |
|
|
Term
| What is the neutral theory? |
|
Definition
- neutral mutations (with significant effect) and positive mutations will survive; -ve mutations will die out
- mutations that cause AA substitutions are often -ve or neutral, very few favourable |
|
|
Term
| What happens to random mutations that don't die out? |
|
Definition
| They will eventually affect the population as a whole |
|
|
Term
| When there is strong natural selection against an allele, what happens to the frequency of that allele? |
|
Definition
|
|
Term
| What are the three different traits selected for? |
|
Definition
| Directional, stabilizing, discriptive |
|
|
Term
| What is directional selection? |
|
Definition
- phenotypes at 1 end of spectrum are selected for/against
- eventual shift towards that end |
|
|
Term
| What is Stabilizing selection? |
|
Definition
- intermediate phenotypes are favoured, extremes are selected against
- population variance will decrease over time, mean stays the same |
|
|
Term
| What is disruptive selection? |
|
Definition
| - both extremes are selected for, intermediates selected against - distribution will become increasingly bimodal |
|
|
Term
|
Definition
| - only process that change in allele frequencies in gene pool |
|
|
Term
|
Definition
| - number of new mutant alleles per number of gametes |
|
|
Term
|
Definition
- when individuals move between populations
- causes a gradient in allele frequencies across geographic regions as populations find resources and stop migrating |
|
|
