Question 1

What is the variance for the mother's and daughter's heights?

Accepted Answer

A) Mothers: 42.21 Daughters: 24.26 
B) Mothers: 41.32 Daughters: 23.71 
C) Mothers: 43.78 Daughters: 24.26 
D) Mothers: 42.21 Daughters 23.78 
A) Mothers: 42.21 Daughters: 24.26 
B) Mothers: 41.32 Daughters: 23.71 
C) Mothers: 43.78 Daughters: 24.26 
D) Mothers: 42.21 Daughters 23.78

Question 2

To use a backcross mating strategy for QTL mapping

Accepted Answer

A) two inbred parental strains that differ in a quantitative trait are crossed are mated. 
B) the F1 offspring are crossed with each other. 
C) the F2 offspring must contain chromosomes that are recombinant betweeen the markers and the genes involved in the trait 
D) each parent should contain the same alleles at each QTL. 
A) two inbred parental strains that differ in a quantitative trait are crossed are mated. 
B) the F1 offspring are crossed with each other. 
C) the F2 offspring must contain chromosomes that are recombinant betweeen the markers and the genes involved in the trait 
D) each parent should contain the same alleles at each QTL.

Question 3

The best definition for genotype-environment interactions is

Accepted Answer

A) Environmental effects on the phenotype differ with genotype. 
B) Environment does not affect phenotype. 
C) Phenotypes will always be affected by the environment no matter what the genotype 
D) Genotypes and phenotypes do not change with environmental conditions 
A) Environmental effects on the phenotype differ with genotype. 
B) Environment does not affect phenotype. 
C) Phenotypes will always be affected by the environment no matter what the genotype 
D) Genotypes and phenotypes do not change with environmental conditions

Question 4

The fact that quantitative traits may be based on a polygenic basis was first discovered in studies of DDT resistance in Drosophila.

Accepted Answer

A) True 
 B)False

Question 5

In QTL mapping, the parental strains are crossed and the F1 generation backcrossed to which of the following?

Accepted Answer

A) The F2 generation 
B) The parental generation 
C) A strain that is homozygous recessive for all markers 
D) A wild-type organism 
A) The F2 generation 
B) The parental generation 
C) A strain that is homozygous recessive for all markers 
D) A wild-type organism

Question 6

In calculations of the degrees of freedom for a correlation coefficient, what value does the degrees of freedom take?

Accepted Answer

A) (n - 1) 
B) (n - 2) 
C) (n - 1)/2 
D) 2(n - 1) 
A) (n - 1) 
B) (n - 2) 
C) (n - 1)/2 
D) 2(n - 1)

Question 7

QTL mapping can rely on the relationship between genes for quantitative traits and which of the following?

Accepted Answer

A) The centromere 
B) Transposon sites 
C) Structural genes 
D) Molecular markers such as RFLPs 
A) The centromere 
B) Transposon sites 
C) Structural genes 
D) Molecular markers such as RFLPs

Question 8

For a quantitative trait, the total variance of the population is due to which of the following?

Accepted Answer

A) The amount of variance due to genetic factors only 
B) The amount of variance due to environmental factors only 
C) The difference between the variance attributed to genetic and environmental factors 
D) The sum of the genetic and environmental variances 
A) The amount of variance due to genetic factors only 
B) The amount of variance due to environmental factors only 
C) The difference between the variance attributed to genetic and environmental factors 
D) The sum of the genetic and environmental variances

Question 9

A selective breeding program is trying to develop an agircultural plant with decreased stem length to aid in mechanical harvesting. The mean stem height of the popluation is 36 cm while the mean stem height of the parents is 30 cm and the mean stem height of the offspring is 33 cm. What is the realized heritability for stem height in this crop?

Accepted Answer

A)  1 
B)  3 
C)  -3 
D)  0.1 
A)  1 
B)  3 
C)  -3 
D)  0.1

Question 10

In an experiment two inbred strains are mated to each other and the offspring demonstrate heterosis. The offspring (F1's) are crossed to each other and a ratio is obtained where there are 9 individuals that demonstrate heterosis and 7 that are similar to the original parental generation. What is this most likely a demonstration of?

Accepted Answer

A) Dominance hypothesis 
B) Overdominance hypothesis 
C) Cannot tell from the information given. 
D) That there is a significant environmental interaction in phenotypic development 
A) Dominance hypothesis 
B) Overdominance hypothesis 
C) Cannot tell from the information given. 
D) That there is a significant environmental interaction in phenotypic development

Question 11

The process of mating between genetically unrelated individuals is called inbreeding.

Accepted Answer

A) True 
 B)False

Question 12

What is the correlation coefficient between mother and daughter height and would it be considered significant?

Accepted Answer

A) Correlation coefficcient: 0.49 Not significant 
B) Correlation coefficcient: 0.31 Not significant 
C) Correlation coefficcient: 0.49 Significant 
D) Correlation coefficcient: 0.31 Significant 
A) Correlation coefficcient: 0.49 Not significant 
B) Correlation coefficcient: 0.31 Not significant 
C) Correlation coefficcient: 0.49 Significant 
D) Correlation coefficcient: 0.31 Significant

Question 13

A population that is homozygous for a given allele is called polymorphic.

Accepted Answer

A) True 
 B)False

Question 14

Heritability is the amount of genetic variation in a particular population and a particular environment.

Accepted Answer

A) True 
 B)False

Question 15

Heritability values can be compared between populations if there is variation in the environmental conditions.

Accepted Answer

A) True 
 B)False

Question 16

Heterosis is _______.

Accepted Answer

A) the combination of lethal alleles due to inbreeding 
B) an increased vigor of hybrids resulting from the crossing of inbred strains 
C) a measurement of the variance due to environmental factors 
D) the result of homozygosity of multiple, dominant, detrimental alleles. 
A) the combination of lethal alleles due to inbreeding 
B) an increased vigor of hybrids resulting from the crossing of inbred strains 
C) a measurement of the variance due to environmental factors 
D) the result of homozygosity of multiple, dominant, detrimental alleles.

Question 17

After calculating a correlation coefficient you discover that the value is not significant at the 5% level. What can be done to produce a significant difference?

Accepted Answer

A) Increase the sample size 
B) Decrease the sample size 
C) Nothing, the value will remain the same regardless of sample size 
A) Increase the sample size 
B) Decrease the sample size 
C) Nothing, the value will remain the same regardless of sample size

Question 18

Inbreeding reduces which of the following variances to near zero?

Accepted Answer

A) Genetic variance 
B) Environmental variance 
C) Both variances 
D) Neither variance 
A) Genetic variance 
B) Environmental variance 
C) Both variances 
D) Neither variance

Question 19

A heritability value of 0.997 indicates which of the following?

Accepted Answer

A) The majority of the phenotypic variation has a genetic basis 
B) The majority of the phenotypic variation has an environmental basis 
C) The trait is polygenic 
D) There is a significant difference between the two strains 
A) The majority of the phenotypic variation has a genetic basis 
B) The majority of the phenotypic variation has an environmental basis 
C) The trait is polygenic 
D) There is a significant difference between the two strains

Question 20

Since quantitative traits are frequently associated with a number of genes and the environment, it is difficult to assign accurate phenotypic classes for a Punnett square diagram.

Accepted Answer

A) True 
 B)False

Exam 27: Quantitative Genetics

What is the variance for the mother's and daughter's heights?

To use a backcross mating strategy for QTL mapping

The best definition for genotype-environment interactions is

The fact that quantitative traits may be based on a polygenic basis was first discovered in studies of DDT resistance in Drosophila.

In QTL mapping, the parental strains are crossed and the F1 generation backcrossed to which of the following?

In calculations of the degrees of freedom for a correlation coefficient, what value does the degrees of freedom take?

QTL mapping can rely on the relationship between genes for quantitative traits and which of the following?

For a quantitative trait, the total variance of the population is due to which of the following?

The process of mating between genetically unrelated individuals is called inbreeding.

What is the correlation coefficient between mother and daughter height and would it be considered significant?

A population that is homozygous for a given allele is called polymorphic.

Heritability is the amount of genetic variation in a particular population and a particular environment.

Heritability values can be compared between populations if there is variation in the environmental conditions.

Heterosis is _______.

After calculating a correlation coefficient you discover that the value is not significant at the 5% level. What can be done to produce a significant difference?

Inbreeding reduces which of the following variances to near zero?

A heritability value of 0.997 indicates which of the following?

Since quantitative traits are frequently associated with a number of genes and the environment, it is difficult to assign accurate phenotypic classes for a Punnett square diagram.

Overview of Genetics

Mendelian Inheritance

Chromosome Transmission During Cell Division and Sexual Reproduction

Extensions of Mendelian Inheritance

Non-Mendelian Inheritance

Genetic Linkage and Mapping in Eukaryotes

Genetic Transfer and Mapping in Bacteria and Bacteriophages

Variation in Chromosome Structure and Number

Molecular Structure of DNA and RNA

Chromosome Organization and Molecular Structure

DNA Replication

Gene Transcription and RNA Modification

Translation of MRNA

Gene Regulation in Bacteria

Gene Regulation in Eukaryotes I: Transcriptional Regulation

Gene Regulation in Eukaryotes II: Epigenetics and Regulation at the RNA Level

Genetics of Viruses

Gene Mutation and Dna Repair

Recombination and Transposition at the Molecular Level

DNA Technologies

Biotechnology

Genomics I: Analysis of DNA

Genomics II: Functional Genomics, Proteomics, and Bioinformatics

Medical Genetics and Cancer

Developmental Genetics

Population Genetics

Evolutionary Genetics

Filters

In QTL mapping, the parental strains are crossed and the F₁ generation backcrossed to which of the following?