Question

if the revcesive allele fir cystic fibrosis is represented as c, classify the following genotypes as homozygous dominant, homozygous recessive,or carriers:CC, Cc, cc. distinguish ehifh which genotype is of an individual who has cystic fibrosis

Answer 1

C = dominant
c = recessive (cystic fibrosis)
CC, cc = homozygous (homo = same)
Cc = heterozygous (hetero = different)

Recessive traits are expressed only when two recessive alleles are present

If you get CC, you will not have cystic fibrosis. (c is the cystic fibrosis allele)
This person would be homozygous dominant and would not pass on the disease because they do not have any cystic fibrosis alleles.

If you get Cc you will not have cystic fibrosis b/c the C is dominant and overrides the cystic fibrosis allele c.
This person would be heterozygous and, though they do not have the disease, they would still have a chance of passing on the disease because they carry the cystic fibrosis allele.

If you get cc you will have cystic fibrosis b/c c is the cystic fibrosis allele and it is not being overridden by a dominant allele.
This person would be homozygous recessive.