It is in your text book .
Check in your text book
If it is a red blood cell than the cell will shrivel because the water will dissolve out of the cell ( because more water flows out of the cell than back into the cell the cell Shrinks )
The centre of the nucleus is an atom
Hybrid = having one recessive and one dominant allele
This means that all of the flowers must have the genotype Bb.
Knowing this, let's make a Punnet Square.

As you can see, 3 of these are going to have the dominant trait and 1 is going to have the recessive trait. This corresponds to our 3:1 in our question, meaning that the black seeds must be dominant and the brown ones recessive.
Because they are dominant, the genotype for black seeds could be
BB <em /><em>or</em>
Bb.