Question 1

Interpret the meaning of an H² (broad-sense heritability)value that approaches 0.0.

Accepted Answer

Almost all the phenotypic variation is determined by the environment.

Question 2

Individuals with the same genetic background and a high degree of homozygosity are said to be isogenic.Of what value are isogenic strains in genetic studies?

Accepted Answer

Because the genetic background is the same (or at least very similar),phenotypic variation must be due to nongenetic factors.

Question 3

Typically,one thinks of identical (MZ)twins being genetically identical.However,genomic differences do exist between MZ twins by epigenetic processes.What are epigenetic processes?

Accepted Answer

Epigenetic processes involve the chemical modification of DNA and associated histones.

Question 4

Quantitative inheritance involves the interaction of a number of gene loci.The pattern of genetic transmission typical of quantitative inheritance is ________.

Accepted Answer

A) discontinuous distributions such as 3:1 
B) typical of Mendelian inheritance 
C) continuous variation of phenotypic expression 
D) a 9:3:3:1 ratio 
E) usually a pattern that clearly reflects dominance and recessiveness 
A) discontinuous distributions such as 3:1 
B) typical of Mendelian inheritance 
C) continuous variation of phenotypic expression 
D) a 9:3:3:1 ratio 
E) usually a pattern that clearly reflects dominance and recessiveness

Question 5

Describe the value of using twins in the study of questions relating to the relative impact of heredity versus environment.

Accepted Answer

Monozygotic twins are derived from the s

Question 6

In the early part of the twentieth century,Nilsson-Ehle and others described experiments showing that multiple loci may be involved in the inheritance of certain traits.Such patterns are often called ________.

Accepted Answer

polygenic

Question 7

Given the following numbers,calculate the mean: 10,12,14,16,18.

Accepted Answer

The answer of Given the following numbers,calculate the mean: 10,12,14,16,18....

Question 8

Assume that four polygenic gene pairs are involved in determining phenotypes of F2.How many phenotypic classes are expected?

Accepted Answer

Question 9

Environmental factors typically influence inheritance of ________.

Accepted Answer

A) multiple alleles 
B) codominance 
C) trihybrid crosses 
D) polygenic traits 
E) dominantly inherited traits 
A) multiple alleles 
B) codominance 
C) trihybrid crosses 
D) polygenic traits 
E) dominantly inherited traits

Question 10

What are the name and formula for describing sample variability?

Accepted Answer

The answer of What are the name and formula for...

Question 11

Assume that you are studying a trait determined by a number of polygenes.If there are seven phenotypic categories,how many genes are probably involved?

Accepted Answer

The answer of Assume that you are studying a trait...

Question 12

What are QTLs and RFLPs?

Accepted Answer

QTLs are quantitative trait lo

Question 13

Which formula can be used to determine the number of categories (phenotypes)possible in the F2 results of a polygenic system?

Accepted Answer

2n + 1 (wh

Question 14

What is the relationship between the narrow-sense heritability (h²)index and the impact of selection?

Accepted Answer

A relatively high h² value is

Question 15

Heritability is a measure of the degree to which the phenotypic variation of a given trait is due to genetic factors.

Accepted Answer

A) True 
 B)False

Question 16

Traits such as height,general body structure,skin color,and some behavioral traits are probably caused primarily by genes that behave codominantly or epistatically.

Accepted Answer

A) True 
 B)False

Question 17

As used in twin studies in mammals,distinguish between the terms concordant and discordant.

Accepted Answer

Concordant refers to a given t

Question 18

When a trait is polygenic but distinguished from continuous and meristic traits by having a small number of discrete classes,it is said to be a(n)________ trait.

Accepted Answer

The answer of When a trait is polygenic but distinguished...

Question 19

How many gene pairs are involved in generating a typical 1:4:6:4:1 ratio?

Accepted Answer

The answer of How many gene pairs are involved in...

Question 20

Name the three components of phenotypic variance.

Accepted Answer

environmental variance (VE),ge

Exam 21: Quantitative Genetics and Multifactorial Traits

Interpret the meaning of an H² (broad-sense heritability)value that approaches 0.0.

Individuals with the same genetic background and a high degree of homozygosity are said to be isogenic.Of what value are isogenic strains in genetic studies?

Typically,one thinks of identical (MZ)twins being genetically identical.However,genomic differences do exist between MZ twins by epigenetic processes.What are epigenetic processes?

Quantitative inheritance involves the interaction of a number of gene loci.The pattern of genetic transmission typical of quantitative inheritance is ________.

Describe the value of using twins in the study of questions relating to the relative impact of heredity versus environment.

In the early part of the twentieth century,Nilsson-Ehle and others described experiments showing that multiple loci may be involved in the inheritance of certain traits.Such patterns are often called ________.

Given the following numbers,calculate the mean: 10,12,14,16,18.

Assume that four polygenic gene pairs are involved in determining phenotypes of F2.How many phenotypic classes are expected?

Environmental factors typically influence inheritance of ________.

What are the name and formula for describing sample variability?

Assume that you are studying a trait determined by a number of polygenes.If there are seven phenotypic categories,how many genes are probably involved?

What are QTLs and RFLPs?

Which formula can be used to determine the number of categories (phenotypes)possible in the F2 results of a polygenic system?

What is the relationship between the narrow-sense heritability (h²)index and the impact of selection?

Heritability is a measure of the degree to which the phenotypic variation of a given trait is due to genetic factors.

Traits such as height,general body structure,skin color,and some behavioral traits are probably caused primarily by genes that behave codominantly or epistatically.

As used in twin studies in mammals,distinguish between the terms concordant and discordant.

When a trait is polygenic but distinguished from continuous and meristic traits by having a small number of discrete classes,it is said to be a(n)________ trait.

How many gene pairs are involved in generating a typical 1:4:6:4:1 ratio?

Name the three components of phenotypic variance.

Introduction to Genetics

Mitosis and Meiosis

Mendelian Genetics

Modification of Mendelian Ratios

Sex Determination and Sex Chromosomes

Chromosome Mutations: Variation in Number and Arrangement

Linkage and Chromosome Mapping in Eukaryotes

Genetic Analysis and Mapping in Bacteria and Bacteriophages

DNA structure and Analysis

DNA Replication and Recombination

Chromosome Structure and DNA Sequence Organization

The Genetic Code and Transcription

Translation and Proteins

Gene Mutation,DNA Repair,and Transposition

Regulation of Gene Expression

The Genetics of Cancer

Recombinant DNA Technology

Genomics,Bioinformatics,and Proteomics

Applications and Ethics of Genetic Engineering and Biotechnology

Developmental Genetics

Population and Evolutionary Genetics

Conservation Genetics

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Assume that four polygenic gene pairs are involved in determining phenotypes of F₂.How many phenotypic classes are expected?

Which formula can be used to determine the number of categories (phenotypes)possible in the F₂ results of a polygenic system?