1. 100% Pink-flowered pea plants:

Pink-flowered pea plant White-flowered pea plant

P1 RR X rr

G 1

♂ ♀	R	R
r	Rr	Rr
r	Rr	Rr

F1 Rr

Pink-flowered pea plants

100%

2. 50% Pink-flowered pea plants and 50% white-flowered pea plants (in the ratio 1:1):

Pink-flowered pea plant White-flowered pea plant

P1 Rr X rr

G1

F1 Rr rr

Pink-flowered pea plants white- flowered pea plants

50% 50%

♂ ♀	R	r
r	Rr	rr
r	Rr	rr

1 : 1

By analyzing these results, Mendel arrived to the possibility of identifying the pair of factors of any allelomorphic characteristic found in an individual.

• If the recessive characteristic appeared in an individual, so it is homozygous (pure) for this recessive characteristic.

• If the dominant characteristic appears in an individual, it may be homozygous (pure), or heterozygous (hybrid).

Thus, if it is crossed with an individual that carries the recessive characteristic, and produced:

- F1 individuals with 100% dominant characteristic, so it is pure dominant.

- F1 individuals with 50% dominant characteristic, and 50% with recessive

characteristic, so it is hybrid dominant.

This type of experiments is known as test cross.

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