Question

question 9
1 pts
assuming complete dominance where each parent is heterozygous for a particular trait, what is the probability that an offspring will express the homozygous recessive condition?
6.25%
25%
50%
75%

Explanation:

Step1: Define genotypes

Let the dominant allele be $A$ and the recessive allele be $a$. Each heterozygous parent has genotype $Aa$.

Step2: Set up Punnett - square

The possible gametes from each parent are $A$ and $a$. The Punnett - square has 4 possible combinations: $AA$, $Aa$, $aA$, $aa$.

Step3: Calculate probability

Out of 4 possible genotypes in the offspring ($AA:Aa:aA:aa = 1:2:1$), the homozygous recessive genotype is $aa$. So the probability of $aa$ is $\frac{1}{4}= 0.25$ or $25\%$.

Answer:

25%