Question

in pea plants purple flowers dominate white. what would be the phenotypic ratio of a cross between 2 heterzygous purple flowers?
○ 3 purple: 1 white
○ 3 white : 1 purple
○ 2 purple: 2 white
○ 2 lavender: 2 white

Explanation:

Step1: Define Alleles

Let \( P \) be dominant (purple), \( p \) recessive (white). Heterozygous: \( Pp \).

Step2: Set Up Punnett Square

Cross \( Pp \times Pp \). Gametes: \( P, p \) from each.

	\( P \)	\( p \)
\( p \)	\( Pp \)	\( pp \)

Step3: Determine Phenotypes

• \( PP, Pp, Pp \): purple (3)
• \( pp \): white (1)

Step4: Phenotypic Ratio

Ratio of purple to white: \( 3:1 \).

Answer:

A. 3 purple: 1 white