Taylor and colleagues performed an experiment on which of the following organisms to provide proof for semi-conservative replication of DNA in chromosomes ?
Taylor and colleagues performed an experiment on which of the following organisms to provide proof for semi-conservative replication of DNA in chromosomes ?
Show Hint
- Garden pea
- Escherichia coli
- Vicia faba
- Drosophila
The Correct Option is C
Solution and Explanation
Meselson and Stahl proved semi-conservative replication in E. coli using heavy nitrogen (\(^{15}\mathrm{N}\)).
Taylor and colleagues showed the same thing in eukaryotic chromosomes.
Step 2: Taylor's experiment:
They grew root tips of the plant Vicia faba (broad bean) with radioactive thymidine and then moved them to a normal medium.
Chromatids were checked after each division. Only one chromatid of each chromosome stayed labelled after the first division, which shows semi-conservative replication.
Step 3: Why the others are wrong:
Garden pea was used by Mendel for inheritance studies, not for this experiment.
E. coli was used by Meselson and Stahl.
Drosophila was used by T. H. Morgan for linkage and sex-linked inheritance.
Final Answer:
Taylor used Vicia faba. This is option (C).
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