Question

cystic fibrosis is a condition that affects mucus. mucus is a jelly - like substance that certain cells produce to protect the body from infection. humans with cystic fibrosis produce mucus that is thicker and stickier than usual. this sticky mucus builds up in the lungs and interferes with breathing.
in a group of humans, some individuals have cystic fibrosis and others do not. in this group, the gene for the cystic fibrosis trait has two alleles. the allele for having cystic fibrosis (f) is recessive to the allele for not having cystic fibrosis (f).
this punnett square shows a cross between two humans.
what is the probability that a human produced by this cross will not have cystic fibrosis?
%

Explanation:

Step1: Determine the genotypes that do not have cystic fibrosis

Since the allele for having cystic fibrosis (\(f\)) is recessive to the allele for not having cystic fibrosis (\(F\)), individuals with genotypes \(FF\) and \(Ff\) do not have cystic fibrosis.

Step2: Count the number of non - cystic fibrosis genotypes in the Punnett square

In the Punnett square, there are 3 genotypes (\(FF\), \(Ff\), \(Ff\)) that do not have cystic fibrosis out of a total of 4 genotypes.

Step3: Calculate the probability

The probability is calculated as \(\frac{\text{Number of non - cystic fibrosis genotypes}}{\text{Total number of genotypes}}\times100\%\). So, \(\frac{3}{4}\times100\% = 75\%\)

Answer:

75