Question

a group of six students has taken samples of their own cheek cells, purified the dna, and used a restriction enzyme known to cut at zero, one, or two sites in a particular gene of interest. analysis of the data obtained shows that two students each have two fragments, two students each have three fragments, and two students each have one only. what does this demonstrate? the two students who have two fragments have one restriction site in this region. each pair of students has a different gene for this function. each of these students is heterozygous for this gene. the two students who have two fragments have two restriction sites within this gene.

Explanation:

Restriction enzymes cut DNA at specific sites. One restriction - site in a gene will result in two DNA fragments when the enzyme cuts. Two sites will result in three fragments and no sites will result in one fragment. The two students with two fragments must have one restriction site in the gene region being studied.

Answer:

The two students who have two fragments have one restriction site in this region.