You take E.coli that has grown in a medium containing only heavy nitrogen ( 15 N ) and tranfer a sample to a medium containing light nitrogen ( 14 N ). After allowing time for two generation, you centrifuge the sample in cesium chloride density gradient. Which band location would support the semiconservative DNA replication after two generations?

Question

You take E.coli that has grown in a medium containing only heavy nitrogen ( 15 N ) and tranfer a sample to a medium containing light nitrogen ( 14 N ). After allowing time for two generation, you centrifuge the sample in cesium chloride density gradient. Which band location would support the semiconservative DNA replication after two generations? (A) Only one DNA ( N 15 N 15) form (B) Only one DNA ( N 15 N 14) form (C) Two DNAs ( N 14 N 15, N 14 N 15) form (D) Three DNAs ( N 14 N 14, N 14 N 15, N 15 N 15) form

Tardigrade Admin · Accepted Answer

Correct answer is (c) Two DNAs ( N 14 N 15, N 14 N 15) form

Only one DNA $(N^{15} N^{15})$ form

Only one DNA $(N^{15} N^{14})$ form

Two DNAs $(N^{14} N^{15}, N^{14} N^{15})$ form

Three DNAs $(N^{14} N^{14}, N^{14} N^{15}, N^{15} N^{15})$ form

Correct answer is (c) Two DNAs $(N^{14} N^{15}, N^{14} N^{15})$ form

Only one DNA (N15N15) form

Only one DNA (N15N14) form

Two DNAs (N14N15,N14N15) form

Three DNAs (N14N14,N14N15,N15N15) form

Correct answer is (c) Two DNAs (N14N15,N14N15) form

Only one DNA $(N^{15} N^{15})$ form

Only one DNA $(N^{15} N^{14})$ form

Two DNAs $(N^{14} N^{15}, N^{14} N^{15})$ form

Three DNAs $(N^{14} N^{14}, N^{14} N^{15}, N^{15} N^{15})$ form

Correct answer is (c) Two DNAs $(N^{14} N^{15}, N^{14} N^{15})$ form