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Question: When HFR conjugates with an \(F^-\) bacterium. the A \(F^-\) cell will convert to \(F^+\) but alw...

When HFR conjugates with an FF^- bacterium. the
A FF^- cell will convert to F+F^+ but always a recombinant
B FF^- cell will convert to F+F^+ but always a not recombinant
C FF^- Hill remain F+F^+ and may or may not be a recombinant
D FF^- will convert to Hfr without recombination

Explanation

Solution

High frequency recombination (Hfr) bacteria are those that have their FF^- plasmid (sex factor) integrated with their chromosomal DNA. The frequency of recombination is quite high in the cross (conjugation) between Hfr cells and FF^- cells, but the frequency of transfer of the entire FF^- factor is relatively low.

Complete answer:
High-frequency recombination cells are abbreviated as HFR. HFR cells are those in which the plasmid has been incorporated into the chromosomal DNA. As a result, when bacteria conjugate with FF^- cells using FF^- plasmid genes, the genes that are closer to the F cells are also transferred to the FF^- cells.
This would result in the F cells forming a partly diploid state, as they may have two sets of some genes. As a result, recombination between homologous genes may be possible in these cells. As a result, the right response is 'FF^- cell will convert to F+F^+, but it will always be a recombinant'.

So option A is the correct answer.

Note:
Bacterial conjugation is the transfer of genetic material between bacterial cells by direct cell-to-cell contact or a bridge-like link. This is accomplished through the use of a pilus. In bacteria, it is a parasexual way of reproduction. It, like transformation and transduction, is a horizontal gene transfer method, however these two do not involve cell-to-cell contact.