Crossing an individual who is homozygous dominant?

Question

Crossing an individual who is homozygous dominant for a trait with an individual whose genotype is unknown will most likely produce which set of offspring?


100% dominant phenotype.


75% dominant phenotype, 25% recessive phenotype.


50% dominant phenotype, 50% recessive phenotype.


100% dominant genotype.

Answer 1

Homozygous dominant crossed with an unknown will result in 100% of the dominant PHENOTYPE -- = answer A.

Answer 2

The first gene from each parent can combine to form an AA offspring. The first from one and the second from the other can combine to form an Aa offspring. The second from one and the first from the other can combine to form an AA offspring. And the second from both parents can combine to form an Aa offspring. So the possibilities are AA, AA, Aa, or Aa: 50% chance of all dominant genes, 50% chance of a combination dominant and recessive. And a 100% chance that the dominant trait will be the visible one. You're welcome. Does this help you to understand it better? There's a little useful chart you could draw but I don't know how to draw it here on yahoo. I'm not in the habit of doing people's homework for them.

Answer 3

100% dominant phenotype.
When the homozygous (BB) is mixed with:

BB: possible genotypes of offspring: BB BB BB BB
Bb: possible genotypes of offspring: BB BB Bb Bb
bb: possible genotypes of offspring: Bb Bb Bb Bb

For all of these, the phenotype will be dominant.

Answer 4

100 % dominant phenotype

XX + XX => 100 % XX

XX + Xx => 50 % XX + 50% Xx

XX + xx => 100% Xx