Monohybrid Cross – Post Lesson Practice

Copy and complete the following sentences.

1. The inheritance of one characteristic is studied in a ______________

cross. In such a cross, the symbol P stands for the _____________

generation and the symbol ____ stands for the first

generation. (3)

2. In peas, the allele for tall (T) is dominant to the allele for dwarf (t).

A true – breeding tall plant has the genotype TT while a true –

breeding dwarf plant has the genotype __________. When these

plants are crossed, all of the F₁ plants have the genotype

_________. (2)

3. The punnett square below shows the genotypes resulting from

crossing F₁ plants with each other.

Tt x Tt

	T	t
T	______	______
t	Tt	______

From the square above, the genotype ratio is 1TT : _____ Tt : 1tt.

The resulting phenotype ratio is _____ tall : 1 dwarf. (5)

Total = 10