Guinea pigs can have either short or long hair. The gene for short hair in guinea pigs is dominant over the gene for long hair. Two short-haired guinea pigs have a litter of eight offspring. Two of the offspring have long hair, and six of the offspring have short hair. What is true about the parent guinea pigs?
A.
The male parent contributed two long hair genes to the offspring.
B.
Only one of the parents carries the gene for long hair.
C.
Both of the parents carry the gene for long hair.
D.
The female parent contributed two long hair genes to the offspring.
B. Only one of the parents carries the gene for long hair.
B. Only one of the parents carries the gene for long hair.
To solve this question, we need to understand the inheritance pattern of hair length in guinea pigs. The gene for short hair is dominant over the gene for long hair, which means that if an individual has at least one copy of the short hair gene, it will have short hair.
Given that two short-haired guinea pigs (which we can assume are homozygous for the short hair gene) have a litter of eight offspring, we can analyze the hair length of the offspring to determine the possible genotypes of the parents.
Out of the eight offspring, two have long hair, and six have short hair. This indicates that both parents must carry the gene for long hair because they passed it down to the two long-haired offspring.
Based on this analysis, the answer to the question is:
C. Both of the parents carry the gene for long hair.