In rats, the following genotypes of two independently assorting autosomal genes determine coat color as follows: A-B- (gray), A-bb (yellow), aaB- (black), aabb (cream). A third gene pair on a separate autosome determines whether or not any color will be produced. DD and Dd genotypes allow color according to the expression of the A and B alleles. However, the dd genotype results in albino rats regardless of alleles of the A and B alleles present. Determine the phenotypic ratios of the offspring from the following crosses: (3 points)
AAbbDD x aaBBdd
AaBBDD x AABbdd
AaBbDd x AaBbDd
Using the information on coat color in rats from the previous problem, determine the genotypes and phenotypes of the parents who produced the following offspring: (2 points)
3/8 black
3/8 cream
2/8 albino
In a family of five children, what is the probability (expressed as a reduced fraction) that: (4 points)
All are males?
Three are males and two are females?
One is male and four are females
The next child will be female?
In rats, the following genotypes of two independently assorting autosomal genes determine coat color as follows: A-B- (gray), A-bb (yellow), aaB- (black), aabb (cream). A third gene pair on a separate autosome determines whether or not any color will be produced. DD and Dd genotypes allow color according to the expression of the A and B alleles. However, the dd genotype results in albino rats regardless of alleles of the A and B alleles present. Determine the phenotypic ratios of the offspring from the following crosses: (3 points)
AAbbDD x aaBBdd
AaBBDD x AABbdd
AaBbDd x AaBbDd
Using the information on coat color in rats from the previous problem, determine the genotypes and phenotypes of the parents who produced the following offspring: (2 points)
3/8 black
3/8 cream
2/8 albino
In a family of five children, what is the probability (expressed as a reduced fraction) that: (4 points)
All are males?
Three are males and two are females?
One is male and four are females
The next child will be female?
Related textbook solutions
Related questions
In rats, several independently assorting autosomal genes affectcoat color. Gene A controls the distribution of yellow pigment inhair, and gene B causes black pigmentation. The two genes interactas follows: AâBâ (gray), Aâbb (yellow), aaBâ (black), and aabb(cream). These genotypes are only expressed in the presence of thedominant allele of a third gene, C; rats with genotype cc arealbino.
a. Deduce the genotype of each albino mice, to the extent thatis possible, in the following table. Explain your answers.
True-breeding parents | F1 | F2 offspring |
Gray x albino-1 | All gray | 3/4 gray : 1/4 albino |
Gray x albino-2 | All gray | 9/16 gray : 3/16 yellow : 4/16 albino |
b. Deduce the genotype and phenotype of each parent in thefollowing table. Explain your answers.
Parents | Numbers of offspring |
Cross 1 | 135 gray, 83 albino, 47 yellow, 44 black, 16 cream |
Cross 2 | 103 albino, 74 black, 25 cream |
c. A gray-colored rat is mated with one that is yellow. Theoffspring include an albino rat and a cream-colored rat. Diagramthis cross. Be sure to include the Punnett square and thephenotypic ratio in the offspring.
In rats, several independently assorting autosomal genes affectcoat color. Gene A controls the distribution of yellowpigment in hair, and gene B causes black pigmentation. Thetwo genes interact as follows: AâBâ (gray), Aâbb(yellow), aaBâ (black), and aabb (cream). Thesegenotypes are only expressed in the presence of the dominant alleleof a third gene, C; rats with genotype cc arealbino.
a. Deduce the genotype of each albino mice, to the extent that ispossible, in the following table. Explain your answers.
True-breeding parents | F1 | F2 offspring |
Gray x albino-1 | All gray | 3/4 gray : 1/4 albino |
Gray x albino-2 | All gray | 9/16 gray : 3/16 yellow : 4/16 albino |
Part a. |
| Genotype of albino-1 parent is ⦠Explanation: |
| Genotype of albino-2 parent is ⦠Explanation: |
b. Deduce the genotype and phenotype of each parent in the followingtable. Explain your answers.
Parents | Numbers of offspring |
Cross 1 | 135 gray, 83 albino, 47 yellow, 44 black, 16 cream |
Cross 2 | 103 albino, 74 black, 25 cream |
Part b. | Parental phenotypes | Parental genotypes |
Cross 1 | x | x |
Explanation: | ||
Part b. | Parental phenotypes | Parental genotypes |
Cross 2 | x | x |
Explanation: | ||
c. A gray-colored rat ismated with one that is yellow. The offspring include an albino ratand a cream-colored rat. Diagram this cross. Be sure to include thePunnett square and the phenotypic ratio in the offspring.
Part c. |
| Cross is ⦠x Explanation: |
Punnett Square
Fill the punnet sq | ||||
Thank you
