The cell theory consists of:
1. all living organisms are made up of cells
2. cells are the basic structural/organizational unit of all organisms
3. all cells come from pre-existing cells
Answer:
1/4
Explanation:
Given that the F2 cross produces offspring according to the expected 9:3:3:1 ratio.
YyRr X YyRr:
Let us break the dihybrid cross into individual monohybrid crosses.
Yy X Yy :
Y y
Y YY Yy
y Yy yy
2/4 or 1/2 of the offspring are heterozygous for the trait.
Similarly, in Rr X Rr cross, 1/2 of the offspring are heterozygous for the trait.
Together, 1/2 * 1/2 = 1/4 of F2 plants are expected to be heterozygous for both traits.
The answer is endocytosis