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1 | |
True or False
- Genes opposite deletions undergo a high frequency of recombination.
- Robertsonian translocations result from the fusion of two small chromosomes end-to-end such that a double centromere occurs.
- Translocation homozygotes usually do not show a problem during meiosis.
- Neither translocations nor inversions alter the amount of DNA in the genome.
- Inversions may be hard to detect because they do not usually cause an abnormal phenotype.
- When a crossover occurs within the inversion loop of a pericentric inversion each recombinant chromatid will have a single centromere.
- In Drosophila, a gynandromorph, which is composed of equal parts male and female tissue, results from a normal egg fertilized by both an X-carrying sperm and a Y-carrying sperm.
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| | A) | F,F,T,T,T,T,F |
| | B) | F,T,T,F,T,F,F |
| | C) | T,F,F,F,T,T,F |
| | D) | T,T,F,F,F,T,T |
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2 | |
A rearrangement that may involve an RNA intermediate is a:
|
| | A) | inversion |
| | B) | duplication |
| | C) | deletion |
| | D) | translocation |
| | E) | transposition |
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3 | |
A change resulting in net loss of DNA is:
|
| | A) | inversion |
| | B) | duplication |
| | C) | deletion |
| | D) | translocation |
| | E) | transposition |
|
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4 | |
A rearrangement which may lead to semisterility is:
|
| | A) | inversion |
| | B) | duplication |
| | C) | deletion |
| | D) | translocation |
| | E) | transposition |
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5 | |
An organism with complete sets of chromosomes is said to be:
|
| | A) | euploid |
| | B) | tetrasomic |
| | C) | aneuploid |
| | D) | allopolyploid |
| | E) | amphidiploid |
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6 | |
Organisms with surpluses or deficits of individual chromosomes are termed:
|
| | A) | euploid |
| | B) | tetrasomic |
| | C) | aneuploid |
| | D) | allopolyploid |
| | E) | amphidiploid |
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7 | |
Organisms with four copies of a particular chromosome are said to be:
|
| | A) | euploid |
| | B) | tetrasomic |
| | C) | aneuploid |
| | D) | allopolyploid |
| | E) | amphidiploid |
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8 | |
Aneuploidy exerts deleterious effects largely through:
|
| | A) | gene dosage |
| | B) | semisterility |
| | C) | mitotic nondisjunction |
| | D) | gynandromorph |
| | E) | mosaic |
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9 | |
Trisomic tissue can arise from:
|
| | A) | gene dosage |
| | B) | semisterility |
| | C) | mitotic nondisjunction |
| | D) | gynandromorph |
| | E) | mosaic |
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10 | |
A heterozygous translocation can result in:
|
| | A) | gene dosage |
| | B) | semisterility |
| | C) | mitotic nondisjunction |
| | D) | gynandromorph |
| | E) | mosaic |
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11 | |
Human L1 and Alu are examples of:
|
| | A) | P elements |
| | B) | transposons |
| | C) | crossover suppressors |
| | D) | LINES & SINES |
| | E) | autonomous elements |
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12 | |
A recent Drosophila transposable element is represented by:
|
| | A) | P elements |
| | B) | transposons |
| | C) | crossover suppressors |
| | D) | LINES & SINES |
| | E) | autonomous elements |
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13 | |
Transposable elements that move their DNA directly are examples of:
|
| | A) | P elements |
| | B) | transposons |
| | C) | crossover suppressors |
| | D) | LINES & SINES |
| | E) | autonomous elements |
|
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14 | |
Transposable elements that contain genes for their own mobilization are called:
|
| | A) | P elements |
| | B) | transposons |
| | C) | crossover suppressors |
| | D) | LINES & SINES |
| | E) | autonomous elements |
|
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15 | |
Chromosomes with rearrangements of particular genes can function as:
|
| | A) | P elements |
| | B) | transposons |
| | C) | crossover suppressors |
| | D) | LINES & SINES |
| | E) | autonomous elements |
|
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16 | |
Transposable element insertion into a gene may result in:
|
| | A) | a splicing defect |
| | B) | frameshift mutations |
| | C) | nonsense mutations |
| | D) | a & b |
| | E) | all of the above |
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17 | |
Chromosomal rearrangements:
|
| | A) | can lead to disease |
| | B) | can improve fitness of an individual of a species |
| | C) | can drive speciation |
| | D) | all of the above |
| | E) | none of the above |
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18 | |
Deletion mutants may be useful for:
|
| | A) | mapping genes |
| | B) | preventing recombination |
| | C) | promoting transposition |
| | D) | a & b |
| | E) | all of the above |
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19 | |
Which of the following are observable cytologically?
|
| | A) | deletion loop |
| | B) | inversion loop |
| | C) | duplication loop |
| | D) | aneuploidy |
| | E) | all of the above |
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20 | |
Which is not true of transposable elements?
|
| | A) | They may leave a copy behind after transposition. |
| | B) | They may be present in a genome from one to thousands of times. |
| | C) | They are always found in all members of a species. |
| | D) | They may not improve fitness of the host organism. |
| | E) | They may revert a gene to wild type after transposition. |
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21 | |
Why are triploid species rare?
|
| | A) | triploidy is always lethal |
| | B) | chromosomes in a triploid cannot segregate equally during meiosis |
| | C) | they usually mate to form hexaploids |
| | D) | chromosomes in a triploid cannot segregate equally during mitosis |
| | E) | none of the above |
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22 | |
Which of the following is an example of a euploid condition?
|
| | A) | polysomy |
| | B) | Turner's syndrome |
| | C) | Down syndrome |
| | D) | tetraploidy |
| | E) | gynandromorph |
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23 | |
Which of the following can contribute to evolution of a species?
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| | A) | amphidiploidy |
| | B) | transposable elements |
| | C) | translocations |
| | D) | all of the above |
| | E) | none of the above |
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24 | |
A very mild case of Down Syndrome is most likely due to __________, caused by __________.
|
| | A) | duplication; transposition |
| | B) | deletion; transposition |
| | C) | tetraploidy; mitotic nondisjunction |
| | D) | mosaicism; mitotic nondisjunction |
| | E) | mosaicism; meiotic nondisjunction |
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25 | |
The following map shows four deletions (1 to 4).
 <![CDATA[<a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=gif:: ::/sites/dl/free/0072919302/56743/chap13mc_img_25.gif','popWin', 'width=380,height=163,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (2.0K)</a>]]>
Five point mutations (a-e) in the region are tested against these four deletion mutants for their ability (+) or inability (-) to give wild-type recombinants, with the following results:
| a | b | c | d | e |
| | 1 |
+ |
+ |
- |
+ |
+ | | 2 |
+ |
+ |
- |
- |
- | | 3 |
- |
- |
+ |
- |
+ | | 4 |
- |
+ |
+ |
+ |
+ |
|
What is the order of the point mutations?
|
| | A) | cedba |
| | B) | dbaced |
| | C) | dbeca |
| | D) | abdec |
| | E) | can't tell |
|