Question

A scientist pollinates a true-breeding pea plant with violet, terminal flowers with pollen from a true-breeding pea plant with white, axial flowers. Which of the following observations would most accurately describe the F2 generation?

a. 75% violet flowers; 75% terminal flowers

b. 75% white flowers in terminal position

c. 75% violet flowers; 75% axial flowers

d. 75% violet flowers in an axial position

Short answer

The correct answer is (c). 75% violet flowers; 75% axial flowers

Step-by-step solution

Introduction

Hybridization in plants was performed by Gregor Mendel for the first time. He mated two individual plants, which were true-breeding and had different traits. Traits are the variations seen in the phenotype, or appearance of heritable characteristics.

Traits can either be dominant or recessive. The traits which are inherited in an unchanged manner in hybridization are dominant. Dominant traits are 100 percent expressed in F₁ generation and 75 percent in F₂ generation.

Explanation for the correct answer

We know, violet and axial are the dominant traits and white and terminal are recessive traits and that dominant traits are 100 percent expressed in F₁ generation and 75 percent in F₂ generation. So in the F₂generation the observation seen will be 75% violet; 75% axial. Hence, option (c) is the correct answer.

Explanation for the incorrect options

a. 75% violet flowers; 75% terminal flowers

Since, terminal flowers are a recessive trait, the observation would show 25% terminal flowers in the F₂generation. Hence, option (a) is the incorrect answer.

b. 75% white flowers in terminal position

Both white color and terminal position are recessive traits. Hence, option (b) is the incorrect answer.

d. 75% violet flowers in an axial position

In F₂generation 75% dominant traits are expressed so the axial position won't be 100% expressed in the F₂generation. Hence, option (d) is the incorrect answer.