First Experiment

1		Because of the way that Creighton and McClintock set up their crosses, there is some ambiguity with regard to phenotype and recombination. For example, colored/starchy kernels could occur in the presence or absence of crossing over. How could the crosses be modified to prevent such ambiguity?
			A)	Change parent A so that both dominant alleles are on the knobbed/ translocation chromosome.
			B)	Change parent A so that both dominant alleles are on the normal chromosome.
			C)	Change parent B so that it is homozygous for both recessive alleles (ccwxwx).
			D)	Change parent B so that it is heterozygous for both genes (CcWxwx).
2		Compared with traits that affect plant morphology, such as tall versus dwarf, why are kernel phenotypes a technically easier option?
			A)	You don't have to wait for the seed to germinate and the plant to grow.
			B)	There are many kernels on one cob.
			C)	Each kernel is relatively small, yet it represents one offspring.
			D)	All of the above
3		If the cross was changed so that parent A had both dominant traits on the knobbed/ translocated chromosome, and both recessive traits on the normal chromosome, and parent B was kept the same as the original experiment, which phenotypes would have to be due to crossing over?
			A)	Colored, waxy
			B)	Colored, waxy and colorless, waxy
			C)	Colorless, waxy
			D)	Colorless, waxy and colored, starchy
4		If the cross was changed so that parent B was homozygous recessive for both genes (ccwxwx) and parent A was kept the same as the original experiment, which phenotypes would have to be due to crossing over?
			A)	Colored, waxy
			B)	Colored, waxy and colorless, waxy
			C)	Colorless, waxy
			D)	Colorless, waxy and colored, starchy
5		In the cross described in Experiment 5A, on rare occasions it is possible to observe a kernel that is colorless/waxy yet does not contain a knobless/translocation chromosome. If we assume that new mutations do not occur in either gene, how could this occur?
			A)	A double crossover, one between both genes and one between the wx gene and the translocation
			B)	A double crossover, both of which occurred between the two genes
			C)	A double crossover, one between both genes and one between the C gene and the knob
			D)	A or C

Second Experiment

6		In constructing his genetic map, Sturtevant did not use the data for which gene pairs
			A)	y and w/we
			B)	y and v
			C)	w/we and v
			D)	v and r
7		In these dihybrid crosses, which parent was heterozygous for two genes?
			A)	The female
			B)	The male
			C)	Both parents
			D)	It doesn't matter.
8		Of the following gene pairs, which data are the most inaccurate due to double crossovers?
			A)	y and w/we
			B)	y and v
			C)	y and r
			D)	y and m
9		Map distance is computed as
			A)	The percentage of parental offspring.
			B)	The percentage of recombinant offspring.
			C)	The number of recombinant offspring divided by the number of parental offspring times 100.
			D)	The number of parental offspring divided by the number of recombinant offspring times 100.
10		The reason why the data for w and we alleles were combined is because
			A)	The numbers were very low.
			B)	The we allele is not X-linked.
			C)	The w allele is not X-linked.
			D)	The w and we alleles are alleles of the same gene.