Question 1

A wholphin is a rare hybrid animal born from mating a female bottlenose dolphin with a male false killer whale. Wholphins are diploid. Interestingly, wholphins are fertile. What can you conclude from the fact that wholphins are fertile?

Accepted Answer

A)   Wholphins are allotetraploid.
B)   Dolphins and false killer whales likely have the same number of chromosomes.
C)   Dolphins and false killer whales are actually the same species.
D)   One of the parents must have been aneuploid.E) None of the above
F) C) and D)

Question 2

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

Accepted Answer

A)   p, q
B)   s, l
C)   q, p
D)   c, dE) B) and C)
F) C) and D)

Question 3

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

Accepted Answer

A) True 
 B)False

Question 4

SMAD4 is a tumor suppressor gene located on chromosome 18 that is known to be homozygously deleted in human lung cancer. If you were to perform comparative genomic hybridization using tissue from a lung cancer patient with a homozygous negative SMAD4 tumor, what ratio of green to red fluorescence would you expect?

Accepted Answer

A)   A ratio of 1 on all of chromosome 18.
B)   A ratio of 2 on the part of chromosome 18 containing the SMAD4 gene, with a value of 1 on the remainder of the chromosome.
C)   A ratio of 0 on all of chromosome 18.
D)   A ratio of 0 on the part of chromosome 18 containing the SMAD4 gene, with a value of 1 on the remainder of the chromosome.
E)   A ratio of 1 on the part of chromosome 18 containing the SMAD4 gene, with a value of 0 on the remainder of the chromosome.F) D) and E)
G) A) and B)

Question 5

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

Accepted Answer

A) True 
 B)False

Question 6

The African clawed frog (Xenopus laevis)  is allotetraploid, likely as a result of an interspecies mating long ago, followed by a duplication of the entire genome. Xenopus laevis is fertile and has a normal life cycle. In contrast, mules, the allodiploid offspring of a male donkey and a female horse, are generally sterile. Why can Xenopus reproduce and mules cannot?

Accepted Answer

A)   Frogs are less sensitive to multiple copies of the genome than mammals.
B)   In allotetraploid organisms each chromosome has a chromosome to pair up with in meiosis, whereas in allodiploid organisms they do not.
C)   The two frogs that interbred to form the Xenopus laevis must have been more closely genetically related than the donkey and horse are.
D)   The mule must have a genetic mutation that prevents it from reproducing.E) B) and C)
F) C) and D)

Question 7

Homologous genes within a species are called paralogs.

Accepted Answer

A) True 
 B)False

Question 8

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

Accepted Answer

A) True 
 B)False

Question 9

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 C D * E F G H

Accepted Answer

A)   Terminal deletion
B)   Interstitial deletion
C)   Inversion
D)   Gene duplicationE) B) and D)
F) A) and B)

Question 10

A photographic representation of the chromosomes of an organism is called a(n)  ________.

Accepted Answer

A)   allele variation
B)   chromosomal spreading
C)   chromosome picture
D)   karyotypeE) None of the above
F) A) and D)

Question 11

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

Accepted Answer

A)   Terminal deficiency
B)   Interstitial deficiency
C)   Inversion
D)   Gene duplicationE) B) and C)
F) A) and D)

Exam 8: Variation in Chromosome Structure and Number

Homologous genes within a species are called paralogs.

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified

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

Correct Answer
verified

A photographic representation of the chromosomes of an organism is called a(n) ________.

Correct Answer
verified

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 C D * E F G H

Correct Answer
verified

Correct Answer
verified

A wholphin is a rare hybrid animal born from mating a female bottlenose dolphin with a male false killer whale. Wholphins are diploid. Interestingly, wholphins are fertile. What can you conclude from the fact that wholphins are fertile?

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

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

Correct Answer
verified

Exam 8: Variation in Chromosome Structure and Number

Homologous genes within a species are called paralogs.

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

A photographic representation of the chromosomes of an organism is called a(n) ________.

Correct AnswerverifiedShow Answer

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 C D * E F G H

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

A wholphin is a rare hybrid animal born from mating a female bottlenose dolphin with a male false killer whale. Wholphins are diploid. Interestingly, wholphins are fertile. What can you conclude from the fact that wholphins are fertile?

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

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

Correct AnswerverifiedShow Answer

Correct Answer
verified

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

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
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