J.H. Taylor's experiment which proved that DNA replication is semi-conservative, was done on

Options

A. salivary gland cells of Drosophila melanogaster
B. root tip cells of Vicia faba
C. oocyte of Periplaneta americana
D. cells of Neurospora crassa.

Answer

**Step-by-Step Solution:**

1. **Understanding the Experiment**: J.H. Taylor conducted an experiment in 1958 to demonstrate that DNA replication is semi-conservative. This means that during DNA replication, each of the two resulting DNA molecules contains one original (parental) strand and one newly synthesized strand.

2. **Identifying the Organism**: The experiment was performed using the root tip cells of the plant species *Vicia faba*, commonly known as the broad bean. This plant was chosen because its root tip cells undergo rapid cell division, making it easier to observe the process of DNA replication.

3. **Process of DNA Replication**: In the experiment, the DNA was denatured, which means the double helix structure was unwound to separate the two strands. Each parental strand then served as a template for the synthesis of a new complementary strand.

4. **Observing Results**: After the replication process, the results showed that the new DNA molecules consisted of one parental strand and one new strand, confirming the semi-conservative nature of DNA replication.

5. **Conclusion**: The correct answer to the question is that J.H. Taylor's experiment was conducted on the root tip cells of *Vicia faba*.

**Final Answer**: J.H. Taylor's experiment which proved that DNA replication is semi-conservative was done on the root tip cells of *Vicia faba*.

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