Yes, dominant (B) and recessive (b) alleles on genes, one from each parent.
You can't give what you don't have, so a double-dominant parent (BB) can only give B or, well, B. Same with a double-recessive parent (bb) who can only give b, or b.
A mixed parent (Bb) will present with the physical traits of B (since the dominant allele is expressed and suppresses the recessive allele) but will still be able to pass on either B or b.
Which means that if two parents, the one being BB and the other also BB breeds (BB × BB), their offspring can only have BB alleles (one from each parent) and will only be able to pass on BB. The same goes for bb × bb - the child will only pass on bb alleles. However, if a Bb parent and a Bb parent breeds (Bb × Bb) their kids can either be BB, Bb, Bb, or bb. So there's a 25% chance of their child being BB and a 25% chance of their child being bb. Their kid stands a 50% chance of being Bb (two 25% chances of Bb).
Only bb kids will be able to express their recessive allele as physical trait, e.g. light fur. The moment B steps into the equation, the dominant trait is expressed (e.g. black fur). So while there's a 25% chance of a bb, it's also the only chance for the recessive gene to show, all the other 75% is expressed as if only the dominant genes were present. So you have a 25% chance of having a kid with white fur, and a 75% chance of having a kid with black fur.
You can't give what you don't have, so a double-dominant parent (BB) can only give B or, well, B. Same with a double-recessive parent (bb) who can only give b, or b.
A mixed parent (Bb) will present with the physical traits of B (since the dominant allele is expressed and suppresses the recessive allele) but will still be able to pass on either B or b.
Only bb kids will be able to express their recessive allele as physical trait, e.g. light fur. The moment B steps into the equation, the dominant trait is expressed (e.g. black fur). So while there's a 25% chance of a bb, it's also the only chance for the recessive gene to show, all the other 75% is expressed as if only the dominant genes were present. So you have a 25% chance of having a kid with white fur, and a 75% chance of having a kid with black fur.