You treat a sample of DNA with DNase and run the digested fragments out on an electrophoretic gel.You found mostly long fragments.What can you conclude about this sample of DNA?
A)The sample contains mostly euchromatin.
B)The sample contains relatively few histone proteins.
C)The sample contains mostly heterochromatin.
D)The DNA is from yeast cells.
E)The sample likely represents actively transcribed genes.

Question

Quizplus · Accepted Answer

The presence of mostly long fragments after DNase treatment suggests that the DNA is tightly packed and protected from enzymatic digestion, a characteristic of heterochromatin. Heterochromatin is a densely packed form of DNA, which makes it less accessible to DNase, resulting in longer fragments after digestion.

You Treat a Sample of DNA with DNase and Run