In pea plants, tall (T) is dominant over dwarf (t). What proportion of the offspring of the cross Tt x Tt will be tall?
Correct answer: A. 3/4
- A. 3/4
- B. 1/4
- C. 1/2
- D. All of them
Explanation
The cross gives TT, Tt, Tt and tt, so three of four genotypes contain a dominant allele and appear tall. Only the tt quarter is dwarf, which is the origin of the famous 3:1 phenotypic ratio.
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About Mendel's Laws of Inheritance
Mendelian inheritance explains how alleles separate into gametes and assort during reproduction, producing predictable genotype and phenotype ratios. Questions cover dominance, recessiveness, homozygous and heterozygous conditions, the laws of segregation and independent assortment, monohybrid and dihybrid crosses, test crosses and the limits caused by linked genes.
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