Deck 8: Variation in Chromosome Structure and Number

Question 1

Which of following algebraic expressions would be used to denote a trisomic organism?

A) 3n
B) 2n - 1
C) 2n + 1
D) 2n + 2

Answer 1

C

Question 2

The majority of autosomal aneuploid conditions are lethal, but sex chromosome aneuploids are
usually not lethal.

Answer 2

True

Question 3

A translocation cross may occur in an individual which has which of the following?

A) Reciprocal translocation
B) Unbalanced translocation
C) Simple translocations
D) All of the answers are correct

Answer 3

A

Question 4

Human genetic diseases such a Cri-du-chat, Angelman syndrome and Prader-Willi syndrome are the result of which of the following?

A) Translocations
B) Duplications
C) Deletions
D) Inversions

Question 5

Variations in chromosome structure are important for which of the following reason(s)?

A) Evolution of new species
B) May result in the production of abnormal offspring
C) May alter the phenotype of an organism
D) All of the answers are correct

Question 6

Chromosomes may be identified based on which of the following characteristics?

A) Location of the centromere
B) Banding patterns
C) Size of the chromosome
D) All of the answers are correct

Question 7

Inversions are contained within what percent of the human population?

A) Less than 1%
B) Approximately 2%
C) Approximately 5%
D) Greater than 10%

Question 8

A loss of an internal piece of a chromosome is called a .

A) Reciprocal translocation
B) Terminal deficiency
C) Interstitial deletion
D) Gene duplication

Question 9

Which of the following would have the shortest p arm of the chromosome?

A) Acrocentic
B) Metacentric
C) Telocentric
D) Submetacentric
E) All of the answers would be equal

Question 10

The production of gene families, such as the globin genes is the result of .

A) Inversions
B) Deficiencies
C) Gene duplications
D) Simple translocations
E) None of the answers are correct

Question 11

Edwards and Patau syndrome are examples of .

A) Aneuploidy
B) Allopolyploidy
C) Autopolyploidy
D) Translocations

Question 12

Gene duplications may be caused by which of the following?

A) The crossing over of misaligned chromosomes
B) Deletion of important genetic information
C) Reciprocal translocations
D) Position effect
E) None of the answers are correct

Question 13

The effects of a deficiency on an organism is dependent on the size of the deletion and the importance
of the missing genetic material to the organism.

Question 14

Familial Down syndrome is a result of which of the following?

A) Inversion
B) Deficiency
C) Gene duplication
D) Translocation

Question 15

Inversion loops can occur in which of the following?

A) Paracentric inversions
B) Pericentric inversions
C) Gene duplications
D) Reciprocal translocations
E) Both paracentric inversions and pericentric inversions

Question 16

Klinefelter and Turner syndromes are examples of which of the following?

A) Sex chromosome aneuploidy
B) Autosomal aneuploidy
C) Reciprocal translocations
D) Paracentric inversions

Question 17

Which of the following is not an example of euploidy?

A) Tetraploid
B) Polyploid
C) Triploid
D) Diploid
E) Aneuploid

Question 18

Which of the following rarely has an effect on the phenotype of the individual who carries it?

A) Robertsonian translocation
B) Unbalanced translocation
C) Balanced translocation
D) All of the answers are equally detrimental to the phenotype

Question 19

Given the following sequence of genes on a chromosome, determine what change in chromosome structure occurred. (the * indicates the centromere)
Before A B C D * E F G H after A B C D * E F E F G H

A) Terminal deficiency
B) Interstitial deficiency
C) Inversion
D) Gene duplication

Question 20

An inversion heterozygote contains which of the following?

A) Two homologous chromosomes with inversions
B) Two normal chromosomes
C) One normal chromosome and one chromosome with an inversion
D) None of the answers are correct

Question 21

The term refers to genetic differences between members of the same species.

A) chromosomal variation
B) genetic variation
C) chromosomal deletions
D) polyploidy

Question 22

Homologous genes within a species are called paralogs.

Question 23

Since no genetic material is lost or gained by an inversion, it will only influence the phenotype of the
individual if the breaks that occur are in important regulatory regions for the genes within the inverted sequence.

Question 24

Polyploid plants tend to produce less fruits and flowers, be smaller in size, and cannot adapt as well to
extreme environmental conditions as normal varieties.

Question 25

The polytene chromosomes of Drosophila are an example of .

A) Aneuploidy
B) Polyploidy
C) Translocations
D) Inversion loops
E) None of the answers are correct

Question 26

The aneuploid condition frequently effects the phenotype of an organism.

Question 27

The ends of chromosomes have areas of repeated DNA called centromeres.

Question 28

The short arm of a chromosome is denoted by the letter and the long arm by the letter .

A) p, q
B) s, l
C) q, p
D) c, d

Question 29

Translocations and inversions represent a change in the total genetic material of a chromosome.

Question 30

A translocation represents when a piece of one chromosome is attached to another chromosome.

A) simple
B) complex
C) reciprocal
D) balanced

Question 31

Which of the following types of plants would usually be a seedless variety?

A) Aneuploid
B) Diploid
C) Triploid
D) Tetraploid

Question 32

Which of the following describes an organism with two complete sets of chromosomes from two different species?

A) Tetraploid
B) Aneuploid
C) Allodiploid
D) Allotetraploid

Question 33

Variations in a gene are called allelic variations.

Question 34

Genetic abnormalities that occur before fertilization may result in some tissues of the body differing in their genetic composition. This is called mosaicism.

Question 35

is a drug that is used to experimentally produce polyploidy in organisms.

A) Penicillin
B) Colchicine
C) Polymosca
D) Karyocine

Question 36

Which of the following is/are correct concerning mitotic nondisjunction?

A) It is a relatively rare event
B) It may result in the loss of some chromosomes in some cells
C) An example is a bilateral gyandromorph
D) It usually does not effect all of the cells of the organism
E) All of the answers are correct

Question 37

A photographic representation of the chromosomes of an organism is called a .

A) allele variation
B) chromosomal spreading
C) chromosome picture
D) karyotype

Question 38

The failure of chromosomes to separate during anaphase is called .

A) Synapsis
B) Maternal effect
C) Epistasis
D) Nondisjunction

Question 39

Which human cells exhibit endopolyploidy?

A) Sex cells
B) Nerve cells
C) All somatic cells
D) Liver cells
E) Red blood cells

Question 40

Due to the formation of an inversion loop, sections of DNA may either be duplicated or deleted
depending on the size of the inversion.