Heredity and Evolution — Mendel's Laws

Grade 10 Science — Heredity and Evolution — Mendel's Laws: 25 practice questions with instant scoring and explanations.

1. In a monohybrid cross between a homozygous dominant (TT) and homozygous recessive (tt) plant, what is the genotypic ratio in F1?
2. What is the phenotypic ratio in F2 generation of a monohybrid cross (Tt × Tt)?
3. A dihybrid cross involves how many genes?
4. In a dihybrid cross between AaBb × AaBb, what is the phenotypic ratio of the F2 generation?
5. In Mendel's experiments with pea plants, which trait was dominant?
6. What does the term 'genotype' refer to?
7. The physical manifestation of alleles is called:
8. In a Punnett square for Aa × Aa, what percentage of offspring will be homozygous?
9. Which of Mendel's laws states that traits are inherited independently?
10. In the F1 generation of Tt × Tt cross, the heterozygous offspring percentage is:
11. What is incomplete dominance?
12. In snapdragons, red flowers (RR) and white flowers (WW) produce pink flowers (RW). What is the F1 phenotype?
13. According to Mendel's Law of Dominance, in a monohybrid cross of Tt × Tt, how many phenotypes appear in F1?
14. What is the probability of getting Aa genotype in Aa × aa cross?
15. A test cross is performed between Aa and:
16. In a dihybrid cross, the phenotypic ratio is 9:3:3:1. What does this ratio represent?
17. What is the F1 ratio when crossing TtYy × TtYy for two traits (dihybrid)?
18. Which combination produces the maximum genotypic ratio in F2?
19. In a monohybrid cross Tt × Tt, the homozygous dominant percentage is:
20. What is the chance of producing a homozygous recessive in Tt × Tt cross?
21. Mendel's experiments were based on how many pea plant varieties?
22. The allele responsible for dominant trait is written as:
23. In AaBb × AaBb cross, the probability of getting AaBb is:
24. What does Punnett square help us determine?
25. In an AaBbCc trihybrid cross, how many phenotypic combinations are possible in F2?