EXAM 3 - Mastering Bio Assignment #9

Consider a population of wildflowers in which the frequency of the red allele CR is p = 0.7. What is the frequency of the white allele (CW ) in this population?

0.3

What is the frequency of the A1A2 genotype in a population composed of 20 A1A1 individuals, 80 A1A2 individuals, and 100 A2A2 individuals?

0.4

What are the 5 conditions that must be met for The Hardy-Weinberg Equilibrium?

1. Random mating 2. No mutations 3. Large population size 4. No migration 5. No natural selection

Suppose a BB female mouse mates with a Bb male mouse. Which of the following represents the probabilities of each genotype occurring among their offspring?

1/2 BB, 1/2 Bb

One of the following is NOT a source of genetic variation. See Concept 23.1 (Page 485) - sexual reproduction - alteration of gene number or position - rapid reproduction - mutation - genetic drift

genetic drift

Crossing over, resulting in an increase in genetic variation, occurs between _____.

nonsister chromatids of homologous chromosomes

the frequency of genotype aa

q^2

Which of the following evolutionary forces consistently results in adaptive changes in allele frequencies?

selection

the frequency of genotype Aa

2pq

All the genes in a population are that population's _____.

gene pool

Modern travel along with migration reduces the probability of _____ having an effect on the evolution of humans.

genetic drift

Homologous pairs of chromosomes are lined up independently of other such pairs during _____.

metaphase I

The ease with which humans travel across the globe is likely to increase _____.

gene flow

Which of the following evolutionary forces could create new genetic information in a population? Nonrandom mating Genetic drift Selection Mutation

mutation

The original source of all genetic variation is _____. See Concept 23.1 (Page 485)

mutuation

q is the _________ allele

recessive (a)

the exchanging of chromosome segments is called _____________ and occurs during _________ of meisosis

recombination; prophase I

Genetic drift is a process based on _____.

the role of chance

A mutation occurs when _____.

there is a change in the DNA sequence of a gene

True or false? The Hardy-Weinberg model makes the following assumptions: no selection at the gene in question; no genetic drift; no gene flow; no mutation; random mating.

true

Every few years a giant axe chops off the head of every person who is over 6 feet tall. How will this affect the human population?

Alleles that promote "tallness" will decrease in frequency.

Consider the following mutations to the nucleotide sequence of a gene. Which of these mutations would not alter the reading frame of the gene's genetic message?

a single nucleotide-pair substitution

the frequency of allele a

q

p is the ________ allele

dominant (A)

In human gamete production there is an average of _____ crossover events per chromosome pair.

2 - 3

what is the equation to find the predicted number of offspring for the genotype Aa, if the given population is in Hardy-Weinberg Equilibrium?

2pq

Which of these individuals is a homozygous genotype? aG Aa AG Gg AA

AA

Suppose that a gene for coat color in mice has two alleles, B and b, where B is completely dominant and encodes a black coat color, and b is recessive and encodes a brown coat color. A mouse that is heterozygous has genotype _____, and its phenotype is _____.

Bb; black

Different finch species have beaks of different shapes and sizes. What do these beak differences tell us?

Different finch beak shapes are evidence that finch species adapted to different environments over many generations.

Which of the following are basic components of the Hardy-Weinberg model? - Frequencies of two alleles in a gene pool before and after many random matings - Allele frequencies, number of individuals in the population - Allele frequencies, phenotype frequencies - Allele frequencies in a subset of the population

Frequencies of two alleles in a gene pool before and after many random matings

What genotype frequencies are expected under Hardy-Weinberg equilibrium for a population with allele frequencies of p = 0.8 and q = 0.2 for a particular gene?

The expected genotype frequencies are 0.64, 0.32, and 0.04 for A1A1, A1A2 , and A2A2 , respectively.

What is the frequency of the A1 allele in a population composed of 20 A1A1 individuals, 80 A1A2 individuals, and 100 A2A2 individuals?

The frequency of the A1 allele is 0.3.

Which of the following statements is not a part of the Hardy-Weinberg principle? - Even if allele A1 is dominant to allele A2 , it does not increase in frequency. - If allele frequencies in a population are given by p and q, then genotype frequencies will be given by p 2, 2pq, and q 2 for generation after generation. - When alleles are transmitted according to the rules of Mendelian inheritance, their frequencies do not change over time. - The genotype frequencies in the offspring generation must add up to two.

The genotype frequencies in the offspring generation must add up to two.

the frequency of allele A

p

allele frequency equation

p + q = 1

the frequency of genotype AA

p^2

genotype frequency equation

p^2 + 2pq + q^2 = 1