Question

When crossing an organism that is homozygous recessive for a single trait with a heterozygote, what is the chance of producing an offspring with the homozygous recessive phenotype?A) 0% B) 25% C) 50% D) 75% E) 100%

Answer 1

Answer:

C)   50%

Explanation:

Let the homozygous recessive organism be rr

Let the heterozygote be Rr

If both organism crosses together: Rr × rr

= we have ( Rr, Rr, rr, rr) as their offspring.

The question says; what is the chance of producing an offspring with the homozygous recessive phenotype?

From above, the chance of producing an homozygous recessive is 50%.

i.e (2/4) × 100%

=(1/2)  × 100%

= 50%