One technique for the purification of RNA-protein complexes makes use of these organisms in MS2 tagging. Another technique (10[3])using these organisms (10[1])uses pIII (10[1])and takes advantage of an M13 (10[1])vector. (10[2]-5[1])One form of these organisms, (10[1])in which the Cro and (10[1])cl (10[1])repressors are found, (10[2]-5[2])was first isolated (10[1])by (10[1])Esther Lederberg. (10[1]-5[1])These (10[2]-5[1])organisms (10[4])were (10[1])used to prove that (10[1])DNA (10[1])is genetic (10[5])material (10[3])by (10[2])radiolabeling (10[11]-5[2])with (10[2]-5[1])phosphorus-32 (10[10]-5[1])and sulfur-35 (10[2])in (10[1])the Hershey–Chase (10[2]-5[1])experiment. (10[3]-5[2])One (10[1])variety (-5[1])of these organisms that can undergo a lytic life cycle (10[2])but not (10[2]-5[1])a (10[1])lysogenic (-5[2])life cycle (10[1]-5[3])has a hollow tail (10[2])and an (10[1])icosahedral (10[3])head. (10[5]-5[1])Examples (-5[1])of (10[1])these organisms (10[1]-5[1])include T4 and lambda. (10[1]0[1]-5[1])For 10 points, (10[1])name these viruses that infect bacteria. (10[1])■END■ (10[25]0[2])