Extending Mendelian Genetics - Practice Problems

For the following questions draw all Punnett squares and identify the genotypes and phenotypes in ratio, fraction and percentage.

Example:
Complete Dominance, where R = Red and r = white

A heterozygous (Rr) mother is crossed with a heterozygous (Rr) father:
Rr * Rr

Answer:

Complete Dominance
1. RR * rr, where R=Red r=white
2. Tt * Tt, where T=Tall t=short
3. Tt * tt, where T=Tall t=short

Incomplete Dominance
4. Rr * RR, where R=Red r=white
5. rr * Rr, where R=Red r=white
6. Tt * Tt, where T=Tall t=short

Codominance
7. RR * rr, where R=Red r=blue
8. Rr * RR, where R=Red r=blue
9. Tt * Tt, where T=Tall t=short

Sex-linked Traits
KEY: C=Normal, c=Colorblind, Y=Male
10. CC* cY
11. Cc * CY
12. cc * CY
13. Cc * cY

Multiple Alleles
14. AA * BB
15. AB * ii
16. ii * AA
17. AB * AB

Polygenics
Identify the phenotype where A, B & C = +1 and a, b & c = 0
18. Aa,Bb,Cc
19. aa,bb,Cc
20. AA,Bb,Cc