In the Meselson-Stahl experiment, 15N-labeled cells were shifted to 14N medium a
ID: 166473 • Letter: I
Question
In the Meselson-Stahl experiment, 15N-labeled cells were shifted to 14N medium at what is designated as generation 0. For the semiconservative model of replication, what proportion of 15N-15N, 15N- 14N, and 14N-14N would you expect to find after three replication cycles?
15N-15N
15N-14N
14N-14N
12.5
25%
50%
0%
100%
75%
87.5%
- A. B. C. D. E. F. G.15N-15N
- A. B. C. D. E. F. G.15N-14N
- A. B. C. D. E. F. G.14N-14N
A.12.5
B.25%
C.50%
D.0%
E.100%
F.75%
G.87.5%
Explanation / Answer
After 3 replications, 8 strands were produced out of which two had 15N- 14N and the rest six had 14N - 14N. None of them had 15N - 15N.
So 25 % were 15N - 14N and 75% were 14N - 14N