A group of people are building a house. They have a large package of building materials that needs to be moved. A block and tackle, a type of pulley, is used to pull the material up so it can be set in the back of a truck.
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.
22. C
23. C
24. A
25. B
26. D
27. C
28. C