Question

1. What kind of assortment does the F2 generation exhibit? Which of Mendel’s laws

does it support?

2. What are the genotypes of both of the first parent plants?

3. Why do the F1 generation plants only contain tall plants with red flowers? Why are

there no short plants or white flowers?

4. According to the activity, what is the genotype for the F1 Generation? What is their

phenotype?

5. From the Punnett Square, what is the ratio of short-white flower plants to short-red

flower plants, to tall-white flower plants, to tall-red flower plants?

short-white flower

short-red flower

tall-white flower

tall-red flower

5. From the Excel file, find the ratio of plants from your data of each possible phenotype:

Tall Red

Short Red

Tall White

Short White

6. Does your observed phenotypic results support / refute Mendel’s hypothesis? Why or

why not?

Intermediate Dominance Exercise Questions

1. Why do the heterozygous plants have pink flowers?

2. What is the mean for the number of red, pink, and white flowers that resulted from the

four crosses?

Red

Pink

White

3. What is the phenotype ratio (red : pink : white) in the F2 generation?

Red

Pink

White

4. Why does the F2 generation have the same phenotype and genotype ratios?

5. What phenotype ratio would you expect if the alleles did not show incomplete

dominance?

6. What might be an indication that alleles for a trait exhibited incomplete dominance?

Maize Kernel Color Questions

One Locus

1. What is the ratio of yellow to purple kernels in the one locus maize ear?

Yellow

Purple

2. What is a possible genotype for the yellow kernels on the one locus corn ear?

3. What is a possible genotype for the purple kernels on the one locus corn ear?

4. If all the kernels had the same parents, what is the most probable genotype for the

parents of the one locus corn ear kernels?

YYCCRrPP x YYCCRrPP

Two Loci

1. What is the ratio of white to yellow to purple kernels in the 2 loci ear?

White

Yellow

Purple

2. What is a possible genotype for the white kernels on the two loci corn ear?

3. What is a possible genotype for the yellow kernels on the two loci corn ear?

4. What is a possible genotype for the purple kernels on the two loci corn ear?

5. If all the kernels had the same parents, what is the most probable genotype for the

parents of the two loci corn ear kernels?

Three Loci

1. What is the ratio of yellow to red, to white to purple kernels?

White

Yellow

Red

Purple

2. What is a possible genotype for the white kernels on the three loci corn ear?

3. What is a possible genotype for the yellow kernels on the three loci corn ear?

4. What is a possible genotype for the red kernels on the three loci corn ear?

5. What is a possible genotype for the purple kernels on the three loci corn ear?

6. If all the kernels had the same parents, what is the most probable genotype for the

parents of the two loci corn ear kernels?

Answer 1

1. Independent assortment occurs in the F2 generation and the Law of segregation support this phenomenon, According to this Law, Each gamete receives either a dominant allele or recessive allele.

2. The first plant parent has Homozygous Dominant and Homozygous Recessive
Eg; TT-   Homozygous Dominant

tt - Homozygous Recessive

3. Because F1 generation is always showing the heterozygous genotype TtRr, so T and R alleles are dominant over t & r alleles.

4. The genotype of the F1 generation always shows the mixture of both parents while phenotype is always same as Dominant parent for example

Parent Generation (T - Dominant allele and t - recessive allele )

TT (tall) X tt (short)

gamete T t

F1 generation Tt (Tall)

5. Punnet Square

	TR	Tr	tR	tr
TR	TTRR (tall & red flower)	TTRr (tall & red flower)	TtRR (tall & red flower)	TtRr (tall & red flower)
Tr	TTRr (tall & red flower)	TTrr (tall & white flowe)	TtRr (tall & red flower)	Ttrr (tall & white flowe)
tR	TtRR (tall & red flower)	TtRr (tall & red flower)	ttRR (short & red flower)	ttRr (short & red flower)
tr	TtRr (tall & red flower)	Ttrr (tall & white flowe)	ttRr (short & red flower)	ttrr (short & white flower)

Ratio

short-white flower-1

short-red flower-3

tall-white flower-3

tall-red flower-9

5.1

Tall Red -9

Short Red- 3

Tall White-3

Short White-1

6. Yes, this observation support Mendel hypothesis, For this He proposed law of segregation and independent assortment.

Intermediate Dominance Exercise Questions

1. This phenomenon happened due to Incomplete dominance, in such case dominant allele does not fully suppress the expression of the recessive gene. (Red flower plant RR crossed with white flower plant rr and F1 generation plant shows Pink color due to flower this)

2. Red-4, Pink-7, White-4

3. Red -1, Pink-2,White-1

4. In incomplete dominant, heterozygous genotype is not showing physical appearance as a dominant parent so in this case F2 generation shows the same genotype and phenotype ratio.

Eg- Red flower (RR) x White flower (rr)

R r

Rr (pink)

selfing

Rr x Rr

R r R r

RR (Red), Rr, Rr (Pink), rr (white ) both ratio is 1:2:1

5. Phenotype ratio-

Monohybrid - 3:1, Dihybrid- 9:3:3:1.

dominance?

6. When the dominant allele does not suppress the expression of the recessive allele, this only identifies once F1 generation produced.

Maize Kernel Color Questions

One Locus

1. What is the ratio of yellow to purple kernels in the one locus maize ear?

Yellow - 1

Purple- 3

2. What is a possible genotype for the yellow kernels on the one locus corn ear- pp

3. What is a possible genotype for the purple kernels on the one locus corn ear- PP/Pp

4. If all the kernels had the same parents, what is the most probable genotype for the

parents of the one locus corn ear kernels -

YYCCRrPP x YYCCRrPP - YYCCRrPP

Two Loci

1. What is the ratio of white to yellow to purple kernels in the 2 loci ear?

White- 1

Yellow-1

Purple-3

2. What is a possible genotype for the white kernels on the two loci corn ear- pp

3. What is a possible genotype for the yellow kernels on the two loci corn ear- pp

4. What is a possible genotype for the purple kernels on the two loci corn ear- PP/Pp

5. If all the kernels had the same parents, what is the most probable genotype for the

parents of the two loci corn ear kernels- Pp.

1. What is the ratio of yellow to red, to white to purple kernels?

White

Yellow

Red

Purple

2. What is a possible genotype for the white kernels on the three loci corn ear - PP/ Pp

3. What is a possible genotype for the yellow kernels on the three loci corn ear- pp

4. What is a possible genotype for the red kernels on the three loci corn ear- PP/ Pp

5. What is a possible genotype for the purple kernels on the three loci corn ear - PP/Pp

6. If all the kernels had the same parents, what is the most probable genotype for the

parents of the two loci corn ear kernels- PP/pp