Deck 7: Chromosome Variation

Question 1

If a diploid species 2nhas 52 chromosomes,how many chromosomes would a triploid have?

A)26
B)52
C)78
D)104
E)156

Answer 1

C
78

Question 2

One species has 2n = 32 chromosomes and another species has 24 chromosomes.In an allotriploid of these two species,how many chromosomes would there be?

A)46 or 40
B)56
C)84
D)48 or 36

Answer 2

A
46 or 40

Question 3

In which way can deletions cause abnormal phenotypes?

A)If the centromere is deleted,then the whole chromosome could be lost during meiosis.
B)In a heterozygous deletion,the gene dosage can be affected.
C)A recessive mutation could be expressed if the wild-type allele is deleted.
D)all of the above

Answer 3

D
a ll of the above

Question 4

A diploid species has 2n = 52 chromosomes.If you found a monosomy in a member of this species,how many chromosomes would it have?

A)104
B)54
C)53
D)51
E)52

Question 5

Aneuploids of which chromosomes are less likely to result in a live birth?

A)larger autosomes
B)small autosomes
C)sex chromosomes
D)all of the above
E)none of the above

Question 6

Which is NOT a type of chromosomal mutation?

A)chromosome rearrangement
B)aneuploidy
C)polyploidy
D)point mutation

Question 7

Which is NOT a way that translocations affect a phenotype?

A)Translocated genes may become under the control of different regulatory sequences.
B)Translocations can cause regions of the chromosome to be duplicated.
C)Translocation breaks can disrupt existing gene function.
D)Translocations can influence karyotype evolution.
E)all of the above

Question 8

The expression of some genes is dependent upon their chromosomal position.Which kind of chromosome rearrangement might cause a position-effect phenotype?

A)deletion
B)duplication
C)inversion
D)all of the above

Question 9

Can chromosome duplications cause problems for an organism? Why?

A)Yes.Duplicated regions require DNA to be replicated,which delays the cell cycle and wastes energy.
B)Yes.Duplicated regions increase gene dosage,which affects processes like development that require specific amounts of protein for completion.
C)No.Duplicated regions of chromosomes are looped out and lost during meiosis.
D)No.Duplicated regions of chromosomes do NOT affect gene dosage,because the cell can compensate for extra copies of genes.