Dihybrid problems, herbarium and gene interaction
Answers are for parents and teachers.
1
How many phenotypes form in AaBbCc × aabbcc and in what ratio?
8 phenotypes, ratio 1:1:1:1:1:1:1:1.
2
AaBb × AaBb gave 1280 plants. About how many are A_B_?
720
3
Homozygous red round (AABB) tomato × yellow pear (aabb): write the F1 and the F2 ratio.
F1 all AaBb; F2 9:3:3:1.
4
Compare complementary action and epistasis (one example each).
Complementary: sweet pea 9:7; epistasis: chicken plumage colour 13:3.
5
What precautions are followed when working with a herbarium?
Handle specimens carefully, do not put them in the mouth, follow the teacher, wash hands.