Genetics worksheet with answers

Two Aa parents are crossed. A gives tall plants and is dominant over a, which gives short plants. Click the cell of the Punnett square for an offspring with short plants.

1. 1A × A
2. 2A × a
3. 3a × A
4. 4a × a

In pea plants, purple flowers (A) are dominant over white (a). A plant with genotype AA is crossed with a plant with genotype Aa. What is the probability P that an offspring has purple flowers?

Duchenne muscular dystrophy is X-linked recessive (allele d). A carrier mother, X^DX^d, has children with an unaffected father, X^DY. The mother's gametes run down the side. Click the cell for a carrier daughter.

1. 1X^D × Y
2. 2X^D × X^D
3. 3X^d × Y
4. 4X^d × X^D

Tall (A) is dominant over short (a), and round seeds (B) over wrinkled (b). The genes are on different chromosomes. For the cross AaBb × AaBb, what is the probability P that an offspring is tall, wrinkled seeds?

A recessive condition affects 1 in 2500 of a population in Hardy–Weinberg equilibrium. What fraction f of the population are carriers (heterozygous)?

A recessive condition affects 1% of a population in Hardy–Weinberg equilibrium. What fraction f of the population are carriers (heterozygous)?