Question 1

Chorionic villus sampling (CVS)is sometimes preferred to amniocentesis because results can be provided earlier in the pregnancy.

Accepted Answer

A) True 
 B)False

Question 2

Recently,a gene located on chromosome 3 in humans,FHIT,has been shown to be associated with the significant human malady known as ________.

Accepted Answer

A) cancer 
B) Huntington disease 
C) "mad-cow" disease 
D) Klinefelter syndrome 
E) XYY/XY mosaicism 
A) cancer 
B) Huntington disease 
C) "mad-cow" disease 
D) Klinefelter syndrome 
E) XYY/XY mosaicism

Question 3

Assume that an organism has a haploid chromosome number of 7.There would be 14 chromosomes in a monoploid individual of that species.

Accepted Answer

A) True 
 B)False

Question 4

An expected meiotic pairing configuration in a triploid would be a trivalent.

Accepted Answer

A) True 
 B)False

Question 5

Name two methods used in genetic prenatal diagnostic testing in humans.

Accepted Answer

amniocente

Question 6

Translocations may be pericentric or paracentric.

Accepted Answer

A) True 
 B)False

Question 7

The condition known as cri-du-chat syndrome in humans has a genetic constitution designated as ________.

Accepted Answer

A) 45,X 
B) heteroplasmy 
C) 46,5p- 
D) triploidy 
E) trisomy 
A) 45,X 
B) heteroplasmy 
C) 46,5p- 
D) triploidy 
E) trisomy

Question 8

Trisomy 21,or Down syndrome,occurs when there is a normal diploid chromosomal complement but one (extra)chromosome 21.Although fertility is reduced in both sexes,females have higher fertility than males.Van Dyke et al.(1995; Down Syndrome Research and Practice 3[2]:65-69)summarize data involving children born of Down syndrome individuals.Given the fact that conceptuses with 48 chromosomes (four chromosome 21s)are not likely to survive early development,what percentage of surviving offspring would be expected to have Down syndrome if both parents have Down syndrome?

Accepted Answer

A) One-third of the surviving offspring would be expected to have Down syndrome. 
B) All the children would be expected to have Down syndrome. 
C) None of the surviving offspring would be expected to have Down syndrome. 
D) Two-thirds of the surviving offspring would be expected to have Down syndrome. 
E) One-half of the surviving offspring would be expected to have Down syndrome. 
A) One-third of the surviving offspring would be expected to have Down syndrome. 
B) All the children would be expected to have Down syndrome. 
C) None of the surviving offspring would be expected to have Down syndrome. 
D) Two-thirds of the surviving offspring would be expected to have Down syndrome. 
E) One-half of the surviving offspring would be expected to have Down syndrome.

Question 9

Nondisjunction is viewed as a major cause of aneuploidy.

Accepted Answer

A) True 
 B)False

Question 10

Gene duplications provide an explanation for the origin of gene families.

Accepted Answer

A) True 
 B)False

Question 11

Although the most frequent forms of Down syndrome are caused by a random error,nondisjunction of chromosome 21,Down syndrome occasionally runs in families.The cause of this form of familial Down syndrome is ________.

Accepted Answer

A) an inversion involving chromosome 21 
B) a chromosomal aberration involving chromosome 1 
C) too many X chromosomes 
D) a translocation between chromosome 21 and a member of the D chromosome group 
E) a maternal age effect 
A) an inversion involving chromosome 21 
B) a chromosomal aberration involving chromosome 1 
C) too many X chromosomes 
D) a translocation between chromosome 21 and a member of the D chromosome group 
E) a maternal age effect

Question 12

What is meant by the terms acentric and dicentric?

Accepted Answer

A chromosome without

Question 13

Doubling the chromosomes of a sterile species hybrid with colchicine or cold shock is a method used to produce a fertile species hybrid (amphidiploid).

Accepted Answer

A) True 
 B)False

Question 14

Describe Bar mutations in Drosophila melanogaster.

Accepted Answer

Bar mutations are du

Question 15

Given that a human normally contains 46 chromosomes,give the chromosome number for each of the following conditions:

Turner syndrome (female,no Barr bodies)
Klinefelter syndrome (male,one Barr body)
triploid
Down syndrome (trisomic)
trisomy 13

Accepted Answer

Turner syndrome (female,no Bar

Question 16

Assume that a species has a diploid chromosome number of 24.The term applied to an individual with 25 chromosomes would be triploid.

Accepted Answer

A) True 
 B)False

Question 17

In Drosophila melanogaster (2n = 8),a fly with seven chromosomes could be called a haplo-IV.

Accepted Answer

A) True 
 B)False

Question 18

Trisomics are observed in humans; monosomics are not.Why?

Accepted Answer

Monosomics are invia

Question 19

In general,inversion and translocation heterozygotes are as fertile as organisms whose chromosomes are in the standard arrangement.

Accepted Answer

A) True 
 B)False

Question 20

Familial Down syndrome is caused by a translocation involving chromosome 21.

Accepted Answer

A) True 
 B)False

Exam 6: Chromosome Mutations: Variation in Number and Arrangement

Chorionic villus sampling (CVS)is sometimes preferred to amniocentesis because results can be provided earlier in the pregnancy.

Recently,a gene located on chromosome 3 in humans,FHIT,has been shown to be associated with the significant human malady known as ________.

Assume that an organism has a haploid chromosome number of 7.There would be 14 chromosomes in a monoploid individual of that species.

An expected meiotic pairing configuration in a triploid would be a trivalent.

Name two methods used in genetic prenatal diagnostic testing in humans.

Translocations may be pericentric or paracentric.

The condition known as cri-du-chat syndrome in humans has a genetic constitution designated as ________.

Nondisjunction is viewed as a major cause of aneuploidy.

Gene duplications provide an explanation for the origin of gene families.

Although the most frequent forms of Down syndrome are caused by a random error,nondisjunction of chromosome 21,Down syndrome occasionally runs in families.The cause of this form of familial Down syndrome is ________.

What is meant by the terms acentric and dicentric?

Doubling the chromosomes of a sterile species hybrid with colchicine or cold shock is a method used to produce a fertile species hybrid (amphidiploid).

Describe Bar mutations in Drosophila melanogaster.

Given that a human normally contains 46 chromosomes,give the chromosome number for each of the following conditions: Turner syndrome (female,no Barr bodies) Klinefelter syndrome (male,one Barr body) triploid Down syndrome (trisomic) trisomy 13

Assume that a species has a diploid chromosome number of 24.The term applied to an individual with 25 chromosomes would be triploid.

In Drosophila melanogaster (2n = 8),a fly with seven chromosomes could be called a haplo-IV.

Trisomics are observed in humans; monosomics are not.Why?

In general,inversion and translocation heterozygotes are as fertile as organisms whose chromosomes are in the standard arrangement.

Familial Down syndrome is caused by a translocation involving chromosome 21.

Introduction to Genetics

Mitosis and Meiosis

Mendelian Genetics

Modification of Mendelian Ratios

Sex Determination and Sex Chromosomes

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

Quantitative Genetics and Multifactorial Traits

Population and Evolutionary Genetics

Conservation Genetics

Filters