In guinea pigs, rough coats (with lots of swirly cowlicks) are dominant over smooth coats. If a male homozygous recessive guinea pig is crossed with a female homozygous dominant guinea pig, what are the possible genotypes and phenotypes of the offspring? Complete the Punnett square and the percentages of rough and smooth coated offspring.
To determine the possible genotypes and phenotypes of the offspring, we can use a Punnett square. In this case, we have a male homozygous recessive guinea pig (rr) crossed with a female homozygous dominant guinea pig (RR).
The male's genotype: rr
The female's genotype: RR
The Punnett square for this cross would look like this:
R R
______________
r | Rr Rr |
r | Rr Rr |
From the Punnett square, we can see that all the offspring will have the genotype Rr, which is heterozygous for the rough coat trait.
The possible genotypes of the offspring are: Rr, Rr, Rr, and Rr.
For the phenotypes, since rough coat (with lots of swirly cowlicks) is dominant over smooth coats, all the offspring will have a rough coat phenotype.
Therefore, the possible genotypes of the offspring are Rr, and the possible phenotype is rough coat.
Since all the offspring have the genotype Rr and the same phenotype (rough coat), we can conclude that the percentages of rough and smooth coated offspring are 100% for rough coat and 0% for smooth coat.
Whats the percent for rough and smooth
Apologies for the error in my previous response.
Given that rough coats (R) are dominant over smooth coats (r), the possible genotypes of the offspring are Rr, as shown in the Punnett square.
Since the male parent is homozygous recessive (rr) and the female parent is homozygous dominant (RR), all of the offspring will have the genotype Rr.
To determine the percentage of rough-coated and smooth-coated offspring, we need to calculate the ratio of Rr to rr genotypes.
In this cross, there are no rr genotypes produced, so the percentage of smooth-coated offspring is 0%.
Since all the offspring have the Rr genotype, the percentage of rough-coated offspring is 100%.
Therefore, the percentages are 0% for smooth coat and 100% for rough coat.
To determine the possible genotypes and phenotypes of the offspring in a cross between a male homozygous recessive guinea pig and a female homozygous dominant guinea pig, you can use a Punnett square.
Let's assign the following letters to represent the coat types:
- "R" for the dominant rough coat
- "r" for the recessive smooth coat
Since the male guinea pig is homozygous recessive, its genotype must be "rr". The female guinea pig is homozygous dominant, so its genotype must be "RR".
To create the Punnett square, write the male's genotype on the top of the square and the female's genotype on the left side:
| r | r |
-------------------
R | Rr | Rr |
-------------------
R | Rr | Rr |
From the Punnett square, we can see that all the offspring will have the genotype "Rr" since there is no "rr" combination in the square.
For the phenotypes, the genotype "Rr" corresponds to the rough coat phenotype since the rough coat is dominant over smooth coat. Therefore, all the offspring will have a rough coat phenotype.
In terms of percentages, since all the offspring have the genotype "Rr" (rough coat), the percentage of rough coated offspring will be 100%.