MBIOS 301 General Genetics (Exam 5: Ch. 22, 26, 27)
Assume that a population at Hardy-Weinberg equilibrium undergoes directional selection. The starting p value is 0.6 and the relative fitness values for the homozygous dominant, heterozygous, and homozygous recessive individuals are 1.0, 0.6, and 0.1. What is the mean fitness of the population (rounded to two significant digits)?
.66
If a population is at Hardy-Weinberg equilibrium, at what frequency (decimal form) of the dominant allele is the frequency of heterozygotes maximized?
0.5
In what year did the Human Genome Project officially begin?
1990
Population
A group of individuals of the same species that occupy the same region and can interbreed with one another.
Molecular Marker
A segment of DNA found at a specific site along a chromosome and has properties that enable it to be uniquely recognized using molecular tools such as polymerase chain reaction (PCR) and gel electrophoresis
Hardy-Weinberg Equation
A simple mathematical expression that predicts stability of allele and genotype frequencies from one generation to the next.
How many different chromosomes contain the human genome? A) 24 B) 46 C) 23 D) 44
A) 24
A gene exists in two alleles and the heterozygote has the highest fitness. This scenario is likely to result in : A) Balancing selection B) Directional selection C) Stabilizing selection D) Disruptive selection
A) Balancing selection
Collection of overlapping clones A) Contig B) YAC C) BAC D) Shotgun
A) Contig
What type of map (one word) is based on microscopy? A) Cytogenetic mapping B) Linkage mapping C) Physical mapping D) Chromosome map
A) Cytogenetic mapping
What type of map (one word) is established on the basis of staining to create chromosome banding patterns (e.g. G banding)? A) Cytogenetic mapping B) Linkage mapping C) Physical mapping D) Chromosome map
A) Cytogenetic mapping
What one-word term refers to the total genetic composition of an organism or species? A) Genome B) Gene C) Chromatid D) Karyotype
A) Genome
Marker that's polymorphic due to the number and/or location of restriction enzyme sites. A) Restriction fragment length polymorphism (RFLP) B) Amplified restriction fragment length polymorphism (AFLP) C) Microsatellite, also called a short tandem repeat (STR) D) Single-nucleotide polymorphism (SNP) E) Sequence-tagged site (STS)
A) Restriction fragment length polymorphism (RFLP)
For each of the following, decide if it could be appropriately described as a genome: A) The E. coli chromosome B) Human chromosome 11 C) A complete set of 10 chromosomes in corn D) A copy of the single-stranded RNA packaged into human immunodeficiency virus (HIV)
A) The E. coli chromosome C) A complete set of 10 chromosomes in corn D) A copy of the single-stranded RNA packaged into human immunodeficiency virus (HIV)
A molecular marker is a segment of DNA that is found at a specific location in a genome. A) True B) False
A) True
An STS is a molecular marker. A) True B) False
A) True
An allele that is "fixed" in a population is regarded as "monomorphic". A) True B) False
A) True
Artificial chromosomes are a type of cloning vector. A) True B) False
A) True
Directional selection results in a normal, bell-shaped curve distribution of phenotypes. A) True B) False
A) True
Evolution results in changes to allele frequencies. A) True B) False
A) True
Molecular markers can be polymorphic. A) True B) False
A) True
Subcloning is associated with the technique of chromosome walking. A) True B) False
A) True
The maximum value of "w" is 1.0. A) True B) False
A) True
The measure of the reproductive success of a genotype is called Darwinian fitness. A) True B) False
A) True
We can follow the transmission of molecular markers using molecular techniques such as gel electrophoresis. A) True B) False
A) True
What type of molecular marker is similar to an RFLP but is amplified via PCR?
AFLP
Between RFLP, AFLP, SNP, and microsatellite (STR). Which type(s) can also be classified as a STS?
AFLP, SNP, and microsatellite (STR)
Gene Pool
All of the alleles of every gene in a population.
Type of RFLP marker that's amplified by PCR. A) Restriction fragment length polymorphism (RFLP) B) Amplified restriction fragment length polymorphism (AFLP) C) Microsatellite, also called a short tandem repeat (STR) D) Single-nucleotide polymorphism (SNP) E) Sequence-tagged site (STS)
B) Amplified restriction fragment length polymorphism (AFLP)
Type of artificial chromosome developed from F factors. A) YAC B) BAC C) Shotgun D) Chromosome walking
B) BAC
At equilibrium the allele and genotype frequencies of a population change over time. A) True B) False
B) False
During gel electrophoresis, a microsatellite with more repeats would be found closer to the bottom of the gel than one with fewer repeats. A) True B) False
B) False
Genetic drift is more likely to affect dominant alleles in a population than recessive alleles. A) True B) False
B) False
Most natural populations are in a state of equilibrium according to Hardy-Weinberg. A) True B) False
B) False
We can follow the transmission of a molecular marker by analyzing the phenotype (i.e., the individual's bodily characteristics) of offspring. A) True B) False
B) False The marker may not carry a gene that affects phenotype.
All molecular markers are segments of DNA that carry specific genes. A) True B) False
B) False They do not have to carry genes.
If a molecular marker is located relatively close to a gene of interest, what term (one word) is used to describe the relationship between the two? A) Locus B) Linkage C) Map Unit D) Polymorphic
B) Linkage
What type of map (one word) is established on the basis of recombination frequency? A) Cytogenetic mapping B) Linkage mapping C) Physical mapping D) Chromosome map
B) Linkage mapping
The accumulation of new mutations in a population is usually a ______ factor against the fitness of the population. A) Positive B) Negative C) Neutral
B) Negative
Which one of the following is a factor that does not promote widespread changes in allele or genotype frequencies? A) Natural selection B) New mutation C) Migration D) Nonrandom mating E) Genetic drift
B) New mutation
Type of artificial chromosome that contains an ARS. A) Contig B) YAC C) BAC D) Shotgun
B) YAC
Which genetic effect (one word) can influence genetic drift via significant changes in the gene pool composition due to the loss of population members by particular natural events (e.g. disease)?
Bottleneck
Technique that involves cloning, subcloning, and library screening. A) BAC B) Shotgun C) Chromosome walking D) Comparative genetics
C) Chromosome walking
Marker that's polymorphic due to differences in the number of repeat units present. A) Restriction fragment length polymorphism (RFLP) B) Amplified restriction fragment length polymorphism (AFLP) C) Microsatellite, also called a short tandem repeat (STR) D) Single-nucleotide polymorphism (SNP) E) Sequence-tagged site (STS)
C) Microsatellite, also called a short tandem repeat (STR)
What causes differences between alleles of a microsatellite marker? A) Relative restriction enzyme cut site locations B) Relative number of restriction enzyme cut sites C) Number of repeat units D) Differences in a single base E) Relative length of the PCR primers
C) Number of repeat units
What type of map (one word) indicates the actual distance (in bp) between markers or regions? A) Cytogenetic mapping B) Linkage mapping C) Physical mapping D) Chromosome map
C) Physical mapping
What one-word term refers to the study of proteins and how they influence the traits of an organism? A) Cytogenetics B) Protology C) Proteomics D) Genetics
C) Proteomics
Which one of the following category types of molecular markers includes the others? A) STR B) AFLP C) STS D) SNP
C) STS
Sequencing approach based on generating random fragments and determining their bases. A) YAC B) BAC C) Shotgun D) Chromosome walking
C) Shotgun
What term (one word) is used to describe the population that consists of immigrants and the original members?
Conglomerate
What term (one word) is used to represent a set of overlapping clones that represents a physical map of a chromosome?
Contig
In situ hybridization is a type of __________ mapping.
Cytogenetic
Which type of mapping attempts to determine the location of a specific gene relative to the banding pattern of a chromosome?
Cytogenetic
Which type of mapping localizes DNA sequences on chromosomes and allows them to be visualized using a microscope?
Cytogenetic
Gene flow is depends on: A) Migration B) The ability of migrant alleles to be passed on to subsequent generations C) Genetic drift D) A and B E) A and C F) A, B, and C
D) A and B
Use of information from genome projects 2 understand genetic variation in populations. A) BAC B) Shotgun C) Chromosome walking D) Comparative genetics
D) Comparative genetics
In FISH analysis, what binds/hybridizes to the denatured chromosomal DNA? One word. A) Membrane B) Sodium hydroxide C) RNA D) Probe
D) Probe
Marker that's polymorphic due to differences in a single base. A) Restriction fragment length polymorphism (RFLP) B) Amplified restriction fragment length polymorphism (AFLP) C) Microsatellite, also called a short tandem repeat (STR) D) Single-nucleotide polymorphism (SNP) E) Sequence-tagged site (STS)
D) Single-nucleotide polymorphism (SNP)
Chromosomal walking is a type of __________ in which a researcher begins at a specific site on one chromosome and analyzes ________ until the gene of interest is reached. A) DNA sequencing; a series of subclones B) DNA sequencing; bands on a gel C) positional cloning; bands on a gel D) positional cloning; a series of subclones
D) positional cloning; a series of subclones
________ (one word) fitness is defined as the relative likelihood that one genotype will contribute to the gene pool of the next generation compared with other genotypes.
Darwinian
Polymorphic
Describe a gene that commonly exists as two or more alleles in a population.
Type of marker that's amplified by PCR and is present only one time in the genome. A) Restriction fragment length polymorphism (RFLP) B) Amplified restriction fragment length polymorphism (AFLP) C) Microsatellite, also called a short tandem repeat (STR) D) Single-nucleotide polymorphism (SNP) E) Sequence-tagged site (STS)
E) Sequence-tagged site (STS)
1-p
Equivalent expression for q.
Monomorphic
Exists predominantly as a single allele in a population
Which one of the following is NOT a condition/assumption of the Hardy-Weinberg equation? A) No natural selection B) No migration C) No new mutations D) Random mating E) Unchanging allele frequencies in successive generations F) All of the above are correct conditions/assumptions
F) All of the above are correct conditions/assumptions
What are the two possible extreme outcomes for allele frequencies with regards to genetic drift (one word each)?
Fixation and Elimination
Which genetic effect (one word) can influence genetic drift via migration of individuals from one population to another?
Founder
What phrase is used to describe changes in a populations allele frequencies due to random fluctuations? (Two words)
Genetic Drift
What are the four mechanisms that can alter existing genetic variation? Which one of these mechanisms doesn't result in changes to allele frequency?
Genetic drift, natural selection, nonrandom mating, and migration.
Chapter 22
Genomics I: Analysis of DNA
The probability of identical by descent alleles is quantified by the _____ (2 words).
Inbreeding coefficient
Which type of mapping estimates relative distances between DNA segments on the basis of recombination values?
Linkage
In which (one) of the following types of mapping studies do/does a marker need to be polymorphic: Linkage, Cytogenetic, and/or Physical. Explain the rationale for your answer
Linkage because you need to be able to detect recombination.
Darwin and Wallace proposed the theory of evolution by ___________ (2 words).
Natural Selection
In which type of mapping are distances between specific DNA segments computed as the number of nucleotide base pairs?
Physical
Are polymorphisms common or rare in natural populations?
Polymorphisms are common in natural populations
Chapter 26
Population Genetics
What term (one word) describes the field of study in which the roles and interactions of proteins are studied?
Proteomics
Polymorphism
Refers to the observation that many traits display variation within a population.
2pq
Represents the frequency of heterozygotes.
q^2
Represents the frequency of homozygous recessives.
p
Represents the frequency of the dominant allele.
What is a synonymous term for a microsatellite marker?
Short tandem repeat (STR)
What is a "SNP"? SNPs represent _____% of all of variations in DNA sequences that occur among humans.
Single-nucleotide polymorphism (SNP) represent 90% of all of variations in DNA sequences that occur among humans.
Local populations, or demes
Smaller groups in a large population.
Which type of selection reduces the variation of the phenotype range of a trait? (One word)
Stabilizing
Hardy-Weinberg Equilibrium
States that the allele and genotype frequencies do not change over the course of many generations.
Population Genetics
The field of population genetics is concerned with changes in genetic variation within a group of individuals over time.
Genomics
The molecular analysis of the entire genome of a species.
Allele Frequency
The number of copies of an allele in a population over the total number of all alleles for that gene in a population.
Genotype Frequency
The number of individuals with a particular genotype in a population over the total number of individuals in a population.
Single-nucleotide polymorphism (SNP)
The smallest type of genetic change that can occur within a given gene and are also the most common.
Genome
The total genetic composition of an organism or species. For example, the nuclear genome of humans is composed of 22 different autosomes and an X chromosome and (in males) a Y chromosome. In addition, humans have a mitochondrial genome composed of a single circular chromosome.
The units of cytogenetic maps: ______ The units of linkage maps: ______ The units of physical maps: ______
The units of cytogenetic maps: #-letter-# The units of linkage maps: mu or cM The units of physical maps: bp
Consider a population of pea plants that consists of 325 homozygous tall, 500 heterozygous tall, and 400 dwarf plants. On the basis of this information, what is: a. The frequency (decimal form) of the heterozygous plants? b. The sum of the frequencies of all three genotype frequencies. c. The frequency (decimal form) of the dominant allele?
a. 0.41 b. 1 c. 0.47
The mean fitness of a population is calculated based on relative fitness and ______ (one word) frequencies.
genotype
Natural selection acts on _______ that are derived from the individuals' _________.
phenotypes; genotypes
The equation to calculate the selection coefficient is:
s = 1 - W