Question 1

Which of the following kinds of information can be revealed through a family pedigree analysis?

Accepted Answer

A) the chromosomal location of disease-related allele 
B) sex linkage 
C) the DNA sequence of disease-related allele 
D) the source of the original mutation in the disease-related allele 
A) the chromosomal location of disease-related allele 
B) sex linkage 
C) the DNA sequence of disease-related allele 
D) the source of the original mutation in the disease-related allele B

Question 2

Match each of the following genetic conditions with its mode of inheritance. A mode of inheritance may be used once, more than once, or not at all.
-phenylketonuria

Accepted Answer

A) autosomal recessive 
B) autosomal dominant 
C) X-linked recessive 
D) aneuploidy 
E) genomic imprinting 
A) autosomal recessive 
B) autosomal dominant 
C) X-linked recessive 
D) aneuploidy 
E) genomic imprinting A

Question 3

Consider the following genetic study involving two autosomal genes. One of these, eye colour, has the dominant allele (R) for red eye colour and the recessive allele (r) for yellow eye colour. The other has the dominant allele (T) leading to paws with thumbs, while the recessive allele (t) codes for paws without thumbs. Presuming no linkage between the genes, what should be the phenotype ratio of the offspring produced by a testcross (RrTt - rrtt)?

Accepted Answer

A) 1 red-eyed with thumbs: 1 yellow-eyed without thumbs 
B) 3 red-eyed with thumbs: 1 yellow-eyed without thumbs 
C) 1 red-eyed with thumbs: 1 yellow-eyed with thumbs: 1 red-eyed without thumbs: 1 yellow-eyed without thumbs 
D) 9 red-eyed with thumbs: 3 yellow-eyed with thumbs: 3 red-eyed without thumbs: 1 yellow-eyed without thumbs 
A) 1 red-eyed with thumbs: 1 yellow-eyed without thumbs 
B) 3 red-eyed with thumbs: 1 yellow-eyed without thumbs 
C) 1 red-eyed with thumbs: 1 yellow-eyed with thumbs: 1 red-eyed without thumbs: 1 yellow-eyed without thumbs 
D) 9 red-eyed with thumbs: 3 yellow-eyed with thumbs: 3 red-eyed without thumbs: 1 yellow-eyed without thumbs C

Question 4

Suppose two genes a and b are 7.4 map units from each other, and that genes b and c are 5.7 map units from each other. You do a cross to determine the map distance between a and C Which result would indicate that c lies between a and b?

Accepted Answer

A) 2.0 map units 
B) 11.1 map units 
C) 14.8 map units 
D) 15.0 map units 
A) 2.0 map units 
B) 11.1 map units 
C) 14.8 map units 
D) 15.0 map units

Question 5

Who developed the concept of mapping genes on chromosomes when he was an undergraduate student?

Accepted Answer

A) Thomas Morgan 
B) Francis Crick 
C) James Watson 
D) Alfred Sturtevant 
A) Thomas Morgan 
B) Francis Crick 
C) James Watson 
D) Alfred Sturtevant

Question 6

-In the figure, what type of change in the chromosomes is depicted?

Accepted Answer

A) a deletion 
B) a reciprocal translocation 
C) an inversion 
D) a duplication 
A) a deletion 
B) a reciprocal translocation 
C) an inversion 
D) a duplication

Question 7

About half of all flowering plant species, including many important crop plants, belong to which category of chromosomes?

Accepted Answer

A) euploids 
B) haploids 
C) aneuploids 
D) polyploids 
A) euploids 
B) haploids 
C) aneuploids 
D) polyploids

Question 8

Suppose that a man and woman have a son with a rare genetic disorder known to be X-linked. There is no occurrence of the disorder on the woman's side of the family, but the man's brother has it, as does her father. What is the probability that the son's defective allele came from the man?

Accepted Answer

A) 0% 
B) 25% 
C) 50% 
D) 100% 
A) 0% 
B) 25% 
C) 50% 
D) 100%

Question 9

Consider the following genetic study involving two autosomal genes. One of these, eye colour, has the dominant allele (R) for red eye colour and the recessive allele (r) for yellow eye colour. The other has the dominant allele (T) leading to paws with thumbs, while the recessive allele (t) codes for paws without thumbs. If these genes are not linked, what should be the phenotype ratio of the offspring produced by a testcross (RrTt -rrtt)?

Accepted Answer

A) 1 red-eyed with thumbs: 1 yellow-eyed without thumbs 
B) 9 red-eyed with thumbs: 3 yellow-eyed with thumbs: 3 red-eyed without thumbs: 1 yellow-eyed without thumbs 
C) 3 red-eyed with thumbs: 1 yellow-eyed without thumbs 
D) 1 red-eyed with thumbs: 1 yellow-eyed with thumbs: 1 red-eyed without thumbs: 1 yellow-eyed without thumbs 
A) 1 red-eyed with thumbs: 1 yellow-eyed without thumbs 
B) 9 red-eyed with thumbs: 3 yellow-eyed with thumbs: 3 red-eyed without thumbs: 1 yellow-eyed without thumbs 
C) 3 red-eyed with thumbs: 1 yellow-eyed without thumbs 
D) 1 red-eyed with thumbs: 1 yellow-eyed with thumbs: 1 red-eyed without thumbs: 1 yellow-eyed without thumbs

Question 10

Match each of the following genetic conditions with its mode of inheritance. A mode of inheritance may be used once, more than once, or not at all.
-achondroplasia

Accepted Answer

A) autosomal recessive 
B) autosomal dominant 
C) X-linked recessive 
D) aneuploidy 
E) genomic imprinting 
A) autosomal recessive 
B) autosomal dominant 
C) X-linked recessive 
D) aneuploidy 
E) genomic imprinting

Question 11

Prenatal diagnosis techniques such as amniocentesis and chorionic villus sampling involve the removal of cells that were produced by an embryo. What are these cells then used for?

Accepted Answer

A) to test for the presence of mutant alleles or chromosomal alterations 
B) to treat diseases 
C) for implantation to produce pregnancy 
D) to develop embryonic stem cells 
A) to test for the presence of mutant alleles or chromosomal alterations 
B) to treat diseases 
C) for implantation to produce pregnancy 
D) to develop embryonic stem cells

Question 12

If two genes on the same chromosome are located 10 map units from each other, what percentage of the offspring should have a recombinant phenotype?

Accepted Answer

A) about 10% 
B) about 25% 
C) about 50% 
D) about 75% 
A) about 10% 
B) about 25% 
C) about 50% 
D) about 75%

Question 13

Suppose that you are a genetic counsellor, and a couple comes to you with concerns that if they have a child together, it could have hemophilia. Suppose also that neither one of them has hemophilia, but the woman's biological father did have an X-linked recessive form of hemophilia. Which of the following is the best advice you could give them?

Accepted Answer

A) Each of their male offspring will have hemophilia, and each of their female offspring will have a 50% chance of having hemophilia. 
B) None of their offspring should have hemophilia, but each of their female offspring will be carriers for hemophilia. 
C) Each child that they produce will have a 50% chance of having hemophilia. 
D) Each of their male offspring will have a 50% chance of having hemophilia, and while their female offspring should not have hemophilia, they will each have a 50% chance of being carriers. 
A) Each of their male offspring will have hemophilia, and each of their female offspring will have a 50% chance of having hemophilia. 
B) None of their offspring should have hemophilia, but each of their female offspring will be carriers for hemophilia. 
C) Each child that they produce will have a 50% chance of having hemophilia. 
D) Each of their male offspring will have a 50% chance of having hemophilia, and while their female offspring should not have hemophilia, they will each have a 50% chance of being carriers.

Question 14

Suppose that you have discovered a new mutant in Drosophila melanogaster. What kinds of genetic crosses should you do to determine if the allele causing the mutation is inherited as an autosomal dominant trait, an autosomal recessive trait, or a sex-linked trait?

Accepted Answer

You should do at least the following cro

Question 15

In Drosophila melanogaster the allele for long wings is dominant over the allele for vestigial wings, and the allele for a grey body is dominant over the allele for a black body. A testcross was done to check for genetic linkage between the genes for these traits, with the following results for the offspring: 410 flies with long wings and a black body
105 flies with long wings and a grey body
390 flies with vestigial wings and a grey body
95 flies with vestigial wings and a black body
Which of the following best represents the map distance between the genes for these two traits?

Accepted Answer

A) 10.0 map units 
B) 20.0 map units 
C) 40.0 map units 
D) 100.0 map units 
A) 10.0 map units 
B) 20.0 map units 
C) 40.0 map units 
D) 100.0 map units

Question 16

Match each of the following genetic conditions with its mode of inheritance. A mode of inheritance may be used once, more than once, or not at all.
-Angelman syndrome

Accepted Answer

A) autosomal recessive 
B) autosomal dominant 
C) X-linked recessive 
D) aneuploidy 
E) genomic imprinting 
A) autosomal recessive 
B) autosomal dominant 
C) X-linked recessive 
D) aneuploidy 
E) genomic imprinting

Question 17

How does the age of the mother seem to correlate with the incidence of genetic birth defects?

Accepted Answer

A) Defect incidence sometimes increases and sometimes decreases with increasing age. 
B) Defect incidence decreases with increasing age. 
C) Defect incidence increases with increasing age. 
D) Defect incidence has no correlation to age. 
A) Defect incidence sometimes increases and sometimes decreases with increasing age. 
B) Defect incidence decreases with increasing age. 
C) Defect incidence increases with increasing age. 
D) Defect incidence has no correlation to age.

Question 18

Suppose you are a genetic counsellor, and a man and woman come to you with concerns that if they have a child together, it could have cystic fibrosis. Also suppose that genetic tests reveal that the woman is a carrier for cystic fibrosis but the man is NOT. Which of the following is the best advice you could give them?

Accepted Answer

A) Each child that they produce will have a 50% chance of having cystic fibrosis, and the other 50% will be carriers. 
B) They should not have any concerns, because no child that they produce should have cystic fibrosis. 
C) No child that they produce should have cystic fibrosis, but each of their children will have a 50% chance of being a carrier. 
D) Each of their offspring will have cystic fibrosis. 
A) Each child that they produce will have a 50% chance of having cystic fibrosis, and the other 50% will be carriers. 
B) They should not have any concerns, because no child that they produce should have cystic fibrosis. 
C) No child that they produce should have cystic fibrosis, but each of their children will have a 50% chance of being a carrier. 
D) Each of their offspring will have cystic fibrosis.

Question 19

Under which condition would you expect the SRY gene to be switched on?

Accepted Answer

A) if no X chromosome is present 
B) if an X chromosome is present 
C) if a Y chromosome is present 
D) if two X chromosomes are present 
A) if no X chromosome is present 
B) if an X chromosome is present 
C) if a Y chromosome is present 
D) if two X chromosomes are present

Question 20

Suppose that you are working in a research lab on the organism Drosophila melanogaster and you have been given the job of determining the relative positions of three linked genes for your undergraduate research project. A graduate student in the lab tells you that gene a is 5.0 centimorgans from gene b, and that gene c is 2.7 centimorgans from gene
b. What should you do to finish mapping these three genes? What results are likely to occur, and how would you interpret such results?

Accepted Answer

To complete this task, one should perfor

Exam 11: Genes, Chromosomes, and Human Genetics

Which of the following kinds of information can be revealed through a family pedigree analysis?

Match each of the following genetic conditions with its mode of inheritance. A mode of inheritance may be used once, more than once, or not at all. -phenylketonuria

Suppose two genes a and b are 7.4 map units from each other, and that genes b and c are 5.7 map units from each other. You do a cross to determine the map distance between a and C Which result would indicate that c lies between a and b?

Who developed the concept of mapping genes on chromosomes when he was an undergraduate student?

-In the figure, what type of change in the chromosomes is depicted?

About half of all flowering plant species, including many important crop plants, belong to which category of chromosomes?

Suppose that a man and woman have a son with a rare genetic disorder known to be X-linked. There is no occurrence of the disorder on the woman's side of the family, but the man's brother has it, as does her father. What is the probability that the son's defective allele came from the man?

Match each of the following genetic conditions with its mode of inheritance. A mode of inheritance may be used once, more than once, or not at all. -achondroplasia

Prenatal diagnosis techniques such as amniocentesis and chorionic villus sampling involve the removal of cells that were produced by an embryo. What are these cells then used for?

If two genes on the same chromosome are located 10 map units from each other, what percentage of the offspring should have a recombinant phenotype?

Suppose that you have discovered a new mutant in Drosophila melanogaster. What kinds of genetic crosses should you do to determine if the allele causing the mutation is inherited as an autosomal dominant trait, an autosomal recessive trait, or a sex-linked trait?

Match each of the following genetic conditions with its mode of inheritance. A mode of inheritance may be used once, more than once, or not at all. -Angelman syndrome

How does the age of the mother seem to correlate with the incidence of genetic birth defects?

Under which condition would you expect the SRY gene to be switched on?

Light and Life

The Cell: an Overview

Defining Life and Its Origins

Energy and Enzymes

Cell Membranes and Signalling

Cellular Respiration

Photosynthesis

Cell Cycles

Genetic Recombination

Mendel, Genes, and Inheritance

Dna Structure, Replication, and Organization

Gene Structure and Expression

Control of Gene Expression

Dna Technologies

Genomes and Proteomes

Evolution: the Development of the Theory

Microevolution: Changes Within Populations

Species and Macroevolution

Understanding the History of Life on Earth

Humans and Evolution

Bacteria and Archaea

Viruses, Viroids, and Prions: Infectious Biological Particles

Protists

Fungi

Plants

Diversity of Animals 1: Sponges, Radiata, Platyhelminthes, and Protostomes

Diversity of Animals 2: Deuterostomes: Vertebrates and Their Closest Relatives

Population Ecology

Population Interactions and Community Ecology

Ecosystems

Conservation of Biodiversity

Putting Selection to Work

Organization of the Plant Body

Transport in Plants

Reproduction and Development in Flowering Plants

Plant Nutrition

Plant Signals and Responses to the Environment

Introduction to Animal Organization and Physiology

Transport in Animals: the Circulatory System

Reproduction in Animals

Animal Development

Control of Animal Processes: Neural Control

Control of Animal Processes: Neural Control

Control of Animal Processes: Neural Integration

Muscles, Skeletons, and Body Movements

Animal Behaviour

Animal Nutrition

Gas Exchange: the Respiratory System

Regulating the Internal Environment

Defences Against Disease

Conservation and Evolutionary Physiology

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