Understanding the Basics
* Dominant Trait: Black coat color (let's represent this with the letter "B")
* Recessive Trait: Red coat color (let's represent this with the letter "b")
* Genotype: The actual genetic makeup of an individual (e.g., BB, Bb, bb)
* Phenotype: The physical expression of the genes (e.g., black coat, red coat)
Possible Genotypes:
* Black Cocker: Can be either BB (homozygous dominant) or Bb (heterozygous)
* Red Cocker: Must be bb (homozygous recessive)
Solving the Problem
1. The Red Puppies: Since three puppies are red, we know both parents must carry at least one recessive "b" allele.
2. The Black Puppies: Since five puppies are black, at least one parent must carry the dominant "B" allele.
3. Putting It Together: The most likely scenario is that one parent is Bb (black, heterozygous) and the other parent is bb (red, homozygous recessive).
Why this works:
* A Bb parent has a 50% chance of passing on a "B" allele and a 50% chance of passing on a "b" allele.
* A bb parent will always pass on a "b" allele.
When these parents mate, the possible offspring genotypes are:
* Bb: Black (from Bb parent)
* bb: Red (from bb parent)
This 1:1 ratio of black to red puppies matches the observed outcome of 5 black and 3 red.
Therefore, the most likely genotypes of the parents are Bb (black) and bb (red).