In Dachshunds Black is dominate, Chocolate recessive.

If you cross a pure Black dachshund with a Chocolate dachshund, what would be the genotypes and phenotypes?

1. The first thing that we need to do is set up a interpretation key.

   BB or Bb = Black, bb = Chocolate

   
   
   
2. Then we determine the genetic cross in the problem.
   
   BB X bb, Homozygous dominant Black cross with a recessive Chocolate
   
   
3. Next we draw the square, and place the genes. One gene in each column, and one for each row.
   
   

   	B	B
   b
   b

   
   
   
4. We take the letter at the top of each column and place it in each square below
   
   

   	B	B
   b	B	B
   b	B	B

   
   
   
5. We take the letter at the front of each row and place it in each square next to it.
   
   

   	B	B
   b	Bb	Bb
   b	Bb	Bb

   
   
   
6. Now we determine the genotypes and the phenotypes.
   
   

   Ratio	Genotype	Ratio	Phenotype
   4/4	Bb	4/4	100% Black