Question

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 f is for not having cystic fibrosis, and the allele f is for having cystic fibrosis.

troy, a human from this group, has cystic fibrosis. troy has two alleles for having cystic fibrosis.

based on this information, click the blue words to correct any errors in the text.

troys phenotype for the cystic fibrosis gene is ff.

troy has cystic fibrosis. this is troys genotype for the cystic fibrosis trait.

troy is homozygous for the cystic fibrosis gene.

Explanation:

1. For the first sentence: Phenotype refers to observable traits, while genotype is the genetic makeup. Troy has cystic fibrosis, so his genotype is ff, not FF. We need to swap "phenotype" with "genotype" and correct FF to ff.
2. For the second sentence: Having cystic fibrosis is the observable trait (phenotype), not genotype. We need to swap "has" with "phenotype" and "genotype" with "phenotype" is incorrect; instead, correct "genotype" to "phenotype" since the statement describes his observable trait.
3. For the third sentence: Troy has two identical alleles (ff) for the trait, so he is homozygous. This statement is correct and needs no change.

Answer:

1. Troy's genotype for the cystic fibrosis gene is ff.
2. Troy has cystic fibrosis. This is Troy's phenotype for the cystic fibrosis trait.
3. Troy is homozygous for the cystic fibrosis gene.