Choose the best answer.

1		Which of the following descriptions of chromosomes is not correctly matched?
			A)	Metacentric — chromosome arms are almost equal in size.
			B)	Submetacentric — chromosome arms are slightly different in size.
			C)	Acrocentric — chromosome arms are identical in size.
			D)	Telocentric — there is only one chromosome arm.
2		Which of the following is not a type of chromosomal mutation?
			A)	Duplication
			B)	Inversion
			C)	Translocation
			D)	All of these are chromosomal mutations.
			E)	None of these are chromosomal mutations.
3		A duplication is:
			A)	The presence of an extra copy of an existing chromosome.
			B)	The presence of an entirely new piece of chromosomal material.
			C)	The presence of an extra copy of a piece of chromosomal material.
			D)	The result of chromosomal material exchanged between two chromosomes.
			E)	A piece of genetic material which has been moved to a new chromosome.
4		Which explanation for the loss of a terminal piece of a chromosome makes the most sense?
			A)	Only pieces of DNA with centromeres are correctly sorted into daughter nuclei during mitosis.
			B)	Only pieces of DNA with telomeres are correctly sorted into daughter nuclei during mitosis.
			C)	This piece of DNA is recognized as foreign by the cell.
			D)	A and B.
			E)	None of these.
5		Which technique can be used to quickly identify large deficiencies?
			A)	Karyotype analysis.
			B)	Genetic studies.
			C)	Pedigree analysis.
			D)	All of these.
			E)	None of these.
6		Why might gene duplication allow for generation of more genetic variability?
			A)	The second copy of the gene could be expressed under different regulation.
			B)	The second copy of the gene could accumulate mutations which would be lethal if only one copy were present.
			C)	The second copy of the gene could be deleted without effect on the organism.
			D)	A and B.
			E)	None of the above.
7		Which statement regarding the human globin genes is likely to be correct?
			A)	Myoglobin is probably more similar to α-globin than is β-globin.
			B)	α-globin and β-globin are probably more similar to each other than they are to myoglobin.
			C)	The globin genes in mice are probably more similar to those of humans than are globin genes of chimpanzees.
			D)	All of these.
			E)	None of these.
8		Which of the following chromosomal rearrangements would you expect to have the least phenotypic effect on the organism?
			A)	A paracentric inversion.
			B)	A paracentric duplication.
			C)	A deficiency.
			D)	A duplication.
9		Why are unaffected carriers of inversions likely to produce genetically abnormal progeny?
			A)	The inversion chromosome is more likely to be placed in a gamete than the normal chromosome.
			B)	The inversion chromosome is unable to accomplish synapsis with the normal chromosome during meiosis.
			C)	Crossovers cannot occur between inversion and normal chromosomes.
			D)	Crossovers between the inversion and normal chromosomes lead to chromosomes with deletions, deficiencies, or abnormal structure.
10		What do deficiencies, inversions, and translocations have in common?
			A)	They all involve loss of genetic material.
			B)	They all contain normal amounts of genetic material in unusual arrangements.
			C)	They all can be caused by DNA breakage and inaccurate repair.
			D)	They all involve extra genetic material in a karyotype.
11		What do inversions and balanced translocations have in common?
			A)	They both contain a normal amount of DNA.
			B)	They both tend to have mild or no phenotypic consequences.
			C)	They both tend to cause abnormal gamete production.
			D)	All of these.
			E)	None of these.
12		Which of the following is an example of a euploid individual?
			A)	A D. melanogaster embryo with 7 chromosomes.
			B)	A human with 47 chromosomes.
			C)	A plant of a new wheat species with twice the usual number of chromosomes.
			D)	None of these.
13		Which of the following terms could be used to describe the individual whose karyotype is shown in Fig 8.1c?
			A)	Aneuploid.
			B)	Tetraploid.
			C)	Diploid.
			D)	Monosomic.
14		If X inactivation in humans shuts down extra X chromosomes, why do XXY and XXX individuals show any phenotypic effects?
			A)	X inactivation can only shut down one X per cell.
			B)	The extra Barr body takes up physical space in the cell.
			C)	Some X linked genes escape inactivation.
			D)	All of these.
			E)	None of these.
15		Which of the following might cause nondisjunction?
			A)	Failure of synapsis in meiosis I.
			B)	Chromosome breakage.
			C)	Lack of synapsis in mitosis.
			D)	Centromere duplication.
16		An allotetraploid species:
			A)	contains a full diploid set from each of two related species.
			B)	is likely to be able to produce viable gametes.
			C)	may be agriculturally important.
			D)	All of these.
			E)	None of these.
17		Deletions tend to be less harmful than duplications.
			A)	True
			B)	False
18		Members of a gene family may be created by abnormal crossing over.
			A)	True
			B)	False
19		Inversions tend to have more serious phenotypic effects than other chromosomal rearrangements.
			A)	True
			B)	False
20		Alternate and adjacent-1 segregation are equally likely to produce nonviable gametes.
			A)	True
			B)	False
21		Aneuploidy is usually a lethal condition in humans.
			A)	True
			B)	False
22		While plants can often exist as polyploid species, animals cannot.
			A)	True
			B)	False
23		All of the cells within an individual are genetically identical.
			A)	True
			B)	False
24		An allodiploid can be created by fusion of diploid gametes.
			A)	True
			B)	False