(Here's the table used for context)
Family / parent phenotype cross / phenotype ratio in offspring
1 / gray fur x black fur / 3 gray fur: 2 black fur
2 / gray fur x black fur / 0 gray fur: 5 black fur
3 / black fur x black fur / 1 gray fur: 3 black fur
4 / gray fur x gray fur / 4 gray fur: 0 black fur
Using the allele symbols N and n identify the most likely genotype of the parent wolves in family 1 and the most likely genotypes of the parent wolves in family 2. Be sure to identify which genotype is for the parent with gray fur and which genotype is for the parent with black fur in each family.
ok so, I'm having trouble understanding. i believe that the inheritance pattern could be dominant-recessive, but now I'm not too sure. families 1 and 2 have 5 offspring (which doesn't accommodate a dominant-recessive punnett square as that only accounts for 4 offspring). so i tried thinking of it in percentages instead but (in family 1 for example) 2/5 is 40% and 3/5 is 60% so that doesn't work with the dominant-recessive punnett square where each trait is 25%. so either I'm wrong about the inheritance pattern or I'm just full on stupid. someone please help, i don't think I've ever been this confused in bio.
Don't worry! I can help you understand this problem.
To determine the most likely genotypes of the parent wolves, we need to consider the phenotype ratios of their offspring and their inheritance patterns. Let's analyze each family individually:
Family 1:
Cross: Gray fur (unknown genotype) x Black fur (unknown genotype)
Phenotype ratio: 3 gray fur: 2 black fur
To analyze this family, we can assume a simple dominant-recessive inheritance pattern. Let's assign the symbol N for gray fur (dominant) and n for black fur (recessive).
From the phenotype ratio, we can deduce that there is both gray fur and black fur in the offspring. This means that at least one of the parents must be heterozygous, carrying both the dominant (N) and recessive (n) alleles.
Therefore, the most likely genotypes for the parents in Family 1 are:
- Parent with gray fur: Nn (heterozygous)
- Parent with black fur: nn (homozygous recessive)
Family 2:
Cross: Gray fur (unknown genotype) x Black fur (unknown genotype)
Phenotype ratio: 0 gray fur: 5 black fur
From the phenotype ratio, we can see that all the offspring have black fur. This suggests that the gray fur phenotype is not present in the offspring, meaning that both parents in this family must be homozygous recessive for black fur.
Therefore, the most likely genotypes for the parents in Family 2 are:
- Parent with gray fur: nn (homozygous recessive)
- Parent with black fur: nn (homozygous recessive)
In summary:
Family 1: Gray fur parent - Nn, Black fur parent - nn
Family 2: Gray fur parent - nn, Black fur parent - nn
Remember, these are just the most likely genotypes based on the given information. It is important to note that without additional data or confirmation, these genotypes are still speculative.