Ch 11 Section 2 Biology

A man with type AB blood and a woman with type B blood could have a children of which of the following phenotypes? (punnett square)

• A, B, or AB
• AB only
• AB, A or O
• A, B, AB or O

In some cattle the genes for brown hair (B) and for white hair (W) are co-dominant. Cattle with alleles for both brown and white hair, have both brown and white hairs. This condition gives the cattle a reddish color, and is referred to as Roan (BW).  Construct a punnett square and give phenotypic and genotype ratios of the offspring from a cross between a roan cow and a white bull.

 

• genotype BW 100%; phenotype 100% roan
• genotype BW 50% WW 50%;  phenotype roan 50% white 50%
• genotype BB 50% WW 50%;  phenotype  brown 50% white 50%
• geno BW 50% BB 25% WW 25%;  pheno 50% roan 25% white 25% brown

Two newborn babies were accidentally mixed up at the hospital. Determine the parents of the babies by blood type. (punnett square needed)

• Baby 1 Brown and Baby 2 Smith
• Baby 1 Smith and Baby 2 Brown

A cross between two true breeding lines one with dark blue flowers and one with bright white flowers produces F1 offspring that are light blue. When the F1 progeny are crossed a 1:2:1 ratio of dark blue to light blue to white flowers is observed. What genetic phenomenon is consistent with these results?

• epistasis
• incomplete dominance
• codominance
• sex-linked

A female is heterozygous for the recessive X-linked gene for Lesch-Nyhan syndrome, a recessive gene that leads to mental retardation, self-mutilation, and early death. What proportion of her daughters will be "carriers" for the trait? (punnett square)

• 0%
• 25%
• 50%
• 75%

The genotypes of a husband and wife are ii x I^Ai. Among the blood types of their children, how many different genotypes and phenotypes are possible? (punnett square)

• 2 genotypes 3 phenotypes
• 2 genotypes 2 phenotypes
• 2 genotypes 4 phenotypes
• 1 genotype 2 phenotypes

If a mother is heterozygous for a recessive sex-linked trait and her husband has the dominant allele, which one of the following is true about the probabilities for their children? (punnett square)

• All of their sons will have the recessive trait
• Half of their sons will have the recessive trait
• None of their sons will have the recessive trait
• All of their daughters will be heterozygous

Breeding a yellow dog with a brown dog produced puppies with both yellow and brown hairs intermixed. This is an example of:

• codominance
• incomplete dominance
• epistasis
• sex-linked

Which pair of chromosome produces a female offspring?

• a female Y chromosome and a female Y chromosomes
• a female X chromosome and a female X chromosome
• a female X chromosome and a female Y chromosome
• a female Y chromosome and a female X chromosome

Which of these describe the allele that causes hemophilia?   

• carried on the Y chromosome
• present only in males
• carried on the X chromosome
• dominant