The genetics of bacteria：練習題

Which mechanism of horizontal gene transfer in bacteria involves the transfer of DNA from a donor cell to a recipient cell via a bacteriophage vector?

Which of the following describes the outcome of conjugation between an \(\text{F}^+\) strain and an \(\text{F}^-\) strain of Escherichia coli?

Following the entry of a linear single-stranded or double-stranded exogenous donor DNA fragment into a recipient bacterium via transformation or generalized transduction, what must occur for the acquired traits to be stably inherited by daughter cells over successive generations of binary fission?

During bacterial conjugation involving an \(\text{F}^+\) donor and an \(\text{F}^-\) recipient, which structure mediates the initial physical contact between the two cells?

A suspension of live non-virulent, unencapsulated Streptococcus pneumoniae (rough strain) was incubated with a cell-free extract of heat-killed virulent, encapsulated Streptococcus pneumoniae (smooth strain) in the presence of various enzymes before injection into mice. In which scenario will the mice survive?

Name the specific biological process by which a bacterial cell reproduces asexually to generate two genetically identical daughter cells.

Explain the specific role of the F pilus (sex pilus) during bacterial conjugation between an \(\text{F}^+\) donor and an \(\text{F}^-\) recipient cell.

During conjugation involving an \(\text{F}^+\) donor and an \(\text{F}^-\) recipient, outline how a copy of the F plasmid is transferred and maintained as a double-stranded circular plasmid in both cells.

A culture of Escherichia coli cells was subjected to genetic analysis.
(a) Outline the process of bacterial reproduction via binary fission.
(b) Describe how genetic material is transferred between two bacterial cells during conjugation involving an \(\text{F}^+\) donor and an \(\text{F}^-\) recipient cell.

Horizontal gene transfer in bacteria can occur via generalized or specialized transduction mediated by bacteriophages.
(a) Describe how generalized transduction occurs during the lytic cycle of a virulent phage.
(b) Contrast generalized transduction with specialized transduction in terms of the phage cycle involved and the specific bacterial genes that can be transferred.