Question 1

The first eukaryotic transposable elements to be characterized at the molecular level were identified within the genes of which organism?

Accepted Answer

A)  corn
B)  yeast
C)  E.coli
D)  mouse
E)  human B

Question 2

In D.melanogaster,when P cytotype (lab stock)females are crossed to M cytotype (wild)males,the resulting F1 progeny are:

Accepted Answer

A)  normal.
B)  defective.
C)  normal:defective in a 1:1 ratio.
D)  normal:defective in a 1:2:1 ratio.
E)  normal:defective in a 3:1 ratio. A

Question 3

Which of the following scientists discovered the Ac-Ds transposable elements in maize?

Accepted Answer

A)  Marcus Rhoades
B)  Rollins Emerson
C)  Barbara McClintock
D)  George Beadle
E)  All of these scientists made the discovery. C

Question 4

IS-induced mutations are different from missense mutations in that they are:

Accepted Answer

A)  nonrevertible.
B)  less severe.
C)  more severe.
D)  nonpolar.
E)  not reverted by mutagens.

Question 5

Hybridization of single-stranded wild-type DNA with DNA from mutations caused by IS elements characteristically shows (through electron microscopy):

Accepted Answer

A)  chi structures.
B)  unpaired tails.
C)  a single-stranded loop representing IS DNA.
D)  a single-stranded loop representing wild-type DNA.
E)  theta structures.

Question 6

Transposable elements that are comprised of DNA transposons are known as:

Accepted Answer

A)  class 1 elements.
B)  class 2 elements.
C)  class 3 elements.
D)  alpha elements.
E)  D elements.

Question 7

The grasses (such as barley,rice,sorghum,and corn)vary widely in the size of their genomes,yet they are descended from a common ancestor.What accounts for the variation in DNA content (i.e.,the total amount of DNA)?

Accepted Answer

A)  large-scale duplication of genes
B)  large-scale loss of genes
C)  accumulation of LTR retrotransposons
D)  loss of LTR retrotransposons
E)  None of the answer options are correct.

Question 8

A maize plant is homozygous for an allele C^m,caused by the insertion of a Ds element into the coding region of a gene (C)that encodes an enzyme necessary for the synthesis of anthocyanin in maize kernels. a)If this plant also contains an Ac element in its genome,what will be the phenotype of its kernels? Justify your answers. b)If this plant does not contain an Ac element,what will be the kernel phenotype? Justify your answers. c)If the plant does not contain an Ac element,but it does contain an autonomous element for another family of transposon,what will be the kernel phenotype? Justify your answers.

Accepted Answer

The answer of A maize plant is homozygous for an...

Question 9

Transposable elements can cause corn kernels to be spotted if they jump in or out of the color genes during the development of the kernel.However,the size of the spots can vary greatly.In words and diagrams,describe the difference between the two kernels shown below at the molecular and developmental levels.

Accepted Answer

The answer of Transposable elements can cause corn kernels to...

Question 10

In D.melanogaster,when M cytotype (lab stock)females are crossed to P cytotype (wild)males,the resulting F1 progeny are:

Accepted Answer

A)  normal.
B)  defective.
C)  normal:defective in a 1:1 ratio.
D)  normal:defective in a 1:2:1 ratio.
E)  normal:defective in a 3:1 ratio.

Question 11

The movement of transposable elements can cause either forward mutations or reversions.
a)Define "forward mutations" and "reversions," and describe the transposition events that cause these two types of phenotypic changes.
b)Why did Barbara McClintock focus on reversions rather than forward mutations when she first studied the inheritance of transposable elements in maize?

Accepted Answer

The answer of The movement of transposable elements can cause...

Question 12

Transposable elements that transpose via an RNA intermediate is known as:

Accepted Answer

A)  class 1 elements.
B)  class 2 elements.
C)  class 3 elements.
D)  alpha elements.
E)  D elements.

Question 13

Compare and contrast autonomous and nonautonomous transposable elements.

Accepted Answer

The answer of Compare and contrast autonomous and nonautonomous transposable...

Question 14

Bacterial transposon structure can be thought of as:

Accepted Answer

A)  IS sequences flanked by inverted drug-resistance genes.
B)  drug-resistance gene(s) flanked by IS elements.
C)  drug-resistance gene(s) flanked by a pair of mu ( μ\muμ ) phage.
D)  a mu ( μ\muμ ) phage flanked by two IS elements.
E)  resistance gene(s) flanked by inverted resistance transfer factors (RTFs) .

Question 15

a)What is the C-value paradox?
b)What is the explanation for the C-value paradox?

Accepted Answer

The answer of a)What is the C-value paradox?
b)What is the...

Question 16

Match between columns
                        Premises:  humans
 Drosophila
 yeast
 maize

Accepted Answer

The Answer of Dt element and Ty1 element and L1 is...

Question 17

Which of the following statements is/are TRUE about the P elements of Drosophila?

Accepted Answer

A)  P elements are examples of eukaryotic DNA transposons.
B)  P elements are mobilized when females with these elements are crossed to males that lack them.
C)  P elements are silenced in M cytotype.
D)  P elements are examples of eukaryotic DNA transposons that are mobilized when females with these elements are crossed to males that lack them.
E)  P elements are examples of eukaryotic DNA transposons that are silenced in M cytotype.

Question 18

A corn plant is homozygous for a mutant allele that results in no pigment in the seed (i.e.,white).The mutant is caused by Ds insertion that often exits late in seed development,when there is an active Ac element in the genome.The seeds of this plant will be:

Accepted Answer

A)  no pigment (i.e. ,white) .
B)  pigmented all over.
C)  white with small spots of pigment.
D)  white with large spots of pigment.
E)  weakly pigmented.

Question 19

Approximately 45 percent of the human genome is derived from transposable elements,such as LINEs and SINEs.
a)What are LINEs and SINEs?
b)How do LINEs differ from SINEs?
c)How is survival possible with this high a percentage of transposable elements in the human genome?

Accepted Answer

The answer of Approximately 45 percent of the human genome...

Question 20

LINEs differ from retrotransposons in that LINEs do not:

Accepted Answer

A)  encode transposase.
B)  encode reverse transcriptase.
C)  contain LTRs.
D)  transpose in a replicative manner.
E)  contain the transposase gene.

Exam 15: The Dynamic Genome: Transposable Elements

The first eukaryotic transposable elements to be characterized at the molecular level were identified within the genes of which organism?

In D.melanogaster,when P cytotype (lab stock) females are crossed to M cytotype (wild) males,the resulting F₁ progeny are:

Which of the following scientists discovered the Ac-Ds transposable elements in maize?

IS-induced mutations are different from missense mutations in that they are:

Hybridization of single-stranded wild-type DNA with DNA from mutations caused by IS elements characteristically shows (through electron microscopy) :

Transposable elements that are comprised of DNA transposons are known as:

The grasses (such as barley,rice,sorghum,and corn) vary widely in the size of their genomes,yet they are descended from a common ancestor.What accounts for the variation in DNA content (i.e.,the total amount of DNA) ?

In D.melanogaster,when M cytotype (lab stock) females are crossed to P cytotype (wild) males,the resulting F₁ progeny are:

Transposable elements that transpose via an RNA intermediate is known as:

Compare and contrast autonomous and nonautonomous transposable elements.

Bacterial transposon structure can be thought of as:

a)What is the C-value paradox? b)What is the explanation for the C-value paradox?

Match the following transposable elements with the species where it is found.

Which of the following statements is/are TRUE about the P elements of Drosophila?

A corn plant is homozygous for a mutant allele that results in no pigment in the seed (i.e.,white) .The mutant is caused by Ds insertion that often exits late in seed development,when there is an active Ac element in the genome.The seeds of this plant will be:

Approximately 45 percent of the human genome is derived from transposable elements,such as LINEs and SINEs. a)What are LINEs and SINEs? b)How do LINEs differ from SINEs? c)How is survival possible with this high a percentage of transposable elements in the human genome?

LINEs differ from retrotransposons in that LINEs do not:

Exam 15: The Dynamic Genome: Transposable Elements

The first eukaryotic transposable elements to be characterized at the molecular level were identified within the genes of which organism?

In D.melanogaster,when P cytotype (lab stock) females are crossed to M cytotype (wild) males,the resulting F1 progeny are:

Which of the following scientists discovered the Ac-Ds transposable elements in maize?

IS-induced mutations are different from missense mutations in that they are:

Hybridization of single-stranded wild-type DNA with DNA from mutations caused by IS elements characteristically shows (through electron microscopy) :

Transposable elements that are comprised of DNA transposons are known as:

The grasses (such as barley,rice,sorghum,and corn) vary widely in the size of their genomes,yet they are descended from a common ancestor.What accounts for the variation in DNA content (i.e.,the total amount of DNA) ?

In D.melanogaster,when M cytotype (lab stock) females are crossed to P cytotype (wild) males,the resulting F1 progeny are:

Transposable elements that transpose via an RNA intermediate is known as:

Compare and contrast autonomous and nonautonomous transposable elements.

Bacterial transposon structure can be thought of as:

a)What is the C-value paradox? b)What is the explanation for the C-value paradox?

Match the following transposable elements with the species where it is found.

Which of the following statements is/are TRUE about the P elements of Drosophila?

A corn plant is homozygous for a mutant allele that results in no pigment in the seed (i.e.,white) .The mutant is caused by Ds insertion that often exits late in seed development,when there is an active Ac element in the genome.The seeds of this plant will be:

Approximately 45 percent of the human genome is derived from transposable elements,such as LINEs and SINEs. a)What are LINEs and SINEs? b)How do LINEs differ from SINEs? c)How is survival possible with this high a percentage of transposable elements in the human genome?

LINEs differ from retrotransposons in that LINEs do not:

In D.melanogaster,when P cytotype (lab stock) females are crossed to M cytotype (wild) males,the resulting F₁ progeny are:

In D.melanogaster,when M cytotype (lab stock) females are crossed to P cytotype (wild) males,the resulting F₁ progeny are: