If a tall pea plant is crossed with a dwarf pea plant and all first-generation plants are tall, which trait is dominant?
Answer and explanation
Correct answer: Tallness
In a Mendelian cross, a dominant trait is expressed in the heterozygous first-generation offspring, whereas a recessive trait can remain hidden. Let T represent tallness and t represent dwarfness. A pure cross TT × tt produces F1 offspring with genotype Tt; because T is dominant, all F1 plants are tall. Therefore option A, tallness, is correct. Dwarfness is the contrasting recessive trait, and seed shape or colour is unrelated to this cross.
Frequently asked questions
What is the correct answer to this question?
Tallness
Why is this the correct answer?
In a Mendelian cross, a dominant trait is expressed in the heterozygous first-generation offspring, whereas a recessive trait can remain hidden. Let T represent tallness and t represent dwarfness. A pure cross TT × tt produces F1 offspring with genotype Tt; because T is dominant, all F1 plants are tall. Therefore option A, tallness, is correct. Dwarfness is the contrasting recessive trait, and seed shape or colour is unrelated to this cross.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Heredity and Evolution. Topic: Mendel’s laws.
