Mendelian Genetics

Backcross confirmation of Mendel's 2nd law

Let's use the example of the yellow, round seeded F₁.

Backcross	GgWw x ggww
Gametes	GW Gw gW gw

Punnett Square for the backcross

		Female Gametes
		GW	Gw	gW	gw
Male Gametes	gw	GgWw (Yellow, round)	Ggww (Yellow, wrinkled)	ggWw (Green, round)	ggww (Green, wrinkled)

The phenotypic ratio of the test cross is:

• 1 Yellow, Round Seed
• 1 Yellow, Wrinkled Seed
• 1 Green, Round Seed
• 1 Green, Wrinkled Seed