Polygenic Inheritance – Post Lesson Practice

1. Discontinuous variation is where a characteristic shows a

____________ difference unlike ____________ variation where a range

of differences can be seen. (2)

2. ____________ inheritance occurs when characteristics are

controlled by only one gene and show _______________

variation. Characteristics which show continuous variation are

controlled by more than one gene and show _______________

inheritance. The more genes there are for a particular characteristic

the more ___________ there will be. (4)

3. Height in humans is an example of _____________ inheritance

and tongue rolling is an example of ____________ inheritance. (2)

4. The punnett square shows the genotypes of offspring from parents

which are homozygous for genes controlling grain colour in maize.

R₁R₁R₂R₂ x r₁r₁r₂r₂

	r1r2	r1r2
R1R2	________	R1r1R2r2
R1R2	R1r1R2r2	_________

(2)

Total = 10