digestion of macronuclei with micrococcal nuclease showed that this dna sequence is protected from digestion but is left , following digestion , as a single but broad size class of dna fragments several hundred base pairs long , under conditions in which bulk macronuclear dna and rdna were digested to fragments that were multiples of approximately 200 base pairs in length .
C0012854
dna
C0012933
rdna