Module 11. Population Genetics
In a population of frogs, a gene is found in two forms - D, and d. The numbers of individuals with different genotypes for that gene are 30 (DD), 18 (Dd), and 12 (dd). What is the frequency of the heterozygous genotype?
0.3
You have a population where you know people's MN blood types. (M and N are co-dominant.) 50 people are type MM, 30 are type MN and 10 are type NN. What is the allele frequency of M?
0.72
What are the five conditions of the Hardy Weinberg equilibrium?
1. random 2. no migration 3. no gen drift, population is large 4. no natural selection 5. no mutations
extinction vortex
A downward population spiral in which inbreeding and genetic drift combine to cause a small population to shrink and, unless the spiral is reversed, become extinct.
Consider a population of cheetahs, inhabiting a protected area in Africa. In 2012, there were 112 cheetahs in this population. During that year, 60 of those animals reproduced and 48 new cubs were born. What constitutes the gene pool of the new generation made of those 48 new cubs?
All of the alleles of all the genes that were passed from the 60 parents to the 48 new cubs
What are microsatellites used for?
DNA profiling/fingerprinting
What are microsatellites?
Repeating sequences of noncoding DNA whose integrity is maintained in cell division
For Hardy-Weinberg equilibrium to be maintained, what would be true of mutations?
They must be absent
The frequency of a particular allele in a population
allele frequency
consanguinity
blood relationship
population size is dramatically reduced by some events such as earthquake, floods, or human destruction of habitat (
bottleneck effect
Nonrandom mating occues when
certain individuals contribute more to the next generation than others
The founder effect _____ population size and ______ genetic drift
decreases, accelerates
What are three outcomes of a mutation?
deleterious, neutral or beneficial
a small group of individuals leaves a large population to start a new settlement
founder effect
2pq
frequency of heterozygous genotype
p2
frequency of homozygous dominant
Q2
frequency of homozygous recessive genotype
all the alleles of every gene in a population
gene pool
The frequency of a particular genotype in a population
genotype frequency
A population practicing consanguinity has
highly nonrandom mating
sickle cell allele in areas of high malaria is an example of what?
natural selection
is lactose intolerance a genetic trait?
no
The changes in allele frequency that causes genetic drift
occur at random and are unpredictable
what are two examples of founder's effect?
polydactyl and o type blood
The study of how the genetic makeup of a population changes over time
population genetics
What causes inbreeding depression?
populations have low genetic diversity
Consider a population and a gene that has two alleles in this population, designated as P and p. If you divide the number of all the copies of the p allele in the population by the total number of copies of both alleles (P and p) in the population, you will calculate:
the allele frequency of the p allele.
assortative mating
the type of mating that occurs when an organism selects a mating partner positive = similar traits negative = unsimilar traits