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Question
List two differences in tabular form between dominant trait and recessive traits. What percentage/proportion of the plants in the F2 generation/progeny were round, in Mendel's cross between round and wrinkled pea plants?
Solution
Difference between dominant trait and recessive gene/trait
| Dominant Trait | Recessive Trait |
| It is a trait or characteristic, which is able to express itself over another contrasting trait. | It is a trait which is unable to express its effect in the presence of the dominant trait. |
| It can express in both heterozygous and homozygous conditions. | It can express only in homozygous condition. |
Cross between round (RR) and wrinkled (rr) pea plants
Parents RR ⨉ rr
Gametes R r
F1 progeny Rr (round seed)
Selfing in F2 generation
| R | r | |
| R | RR | Rr |
| r | Rr | rr |
Result: In F2 generation, the progeny will be
75% round (RR, Rr)
25% wrinkled (rr)
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