Name – Joshua Fan
Bio-18
Chapter 8 Worksheet
Genetic Analysis and Mapping in Bacteria and Bacteriophages
1. What is a bacteriophage? 1 pts
Viruses that use bacteria as hosts
2. What processes result in transfer of genetic information from one bacterium to another? 1
pts
Conjugation, transduction, and transformation
3. Distinguish between F+ and F- bacteria. 1 pts
F+ bacteria is the donor of parts of their chromosomes bacterial cell while F- is the
recipient cell and recombine with parts of their own chromosomes with the ones they
received.
4. What is a plasmid? 1 pts
A plasmid is composed of double stranded closed circle of DNA.
5. What is transformation? 1 pts
Transformation is a process of horizontal gene transfer by which some bacteria take up
foreign genetic material from the environment.
6. Compare and contrast bacteriophage lysis and lysogeny. 1 pts
Bacteriophage lysis and lysogeny are two different ways for bacteriophages to replicate
and interact with their host bacteria. Lysis leads to the destruction of the host cell and
causes immediate phage release whereas, lysogeny is a more symbiotic relationship
between the phage and host.
7. Bacteriophages that cannot undergo lysogeny but can infect bacteria are called
virulent phages. 0.5 pts
8. True or False. Co-transduction of genes is an indication that the genes are linked.
True 0.5pts
9. Temperate phages are those that can enter either the lysogenic or lytic cycle.
1 pts
10. What are steps of transfer of F factor during conjugation? 2 pts
Attachment, the F+ bacterial cell forms physical contact with the F-
Pilus Formation, F+ cell forms a pilus to bring the F- cell into close proximity.
Formation of Conjugation Bridge, the pilus pulls the F+ and F- cells closer together and
forms a conjugation bridge.
Transfer of F Factor, F factor DNA begins to replicate and one strand is transferred
through the conjugation bridge to the F- cell.
Completion of Transfer: after the entire DNA strand has been transferred to the F- cell,
synthesis of the strand occurs in both cells to restore the double stranded DNA making
both F+ and F- cells F+.
Integration and Synthesis of Complementary strand: the F factor DNA may integrate into
the bacterial chromosome or replicate autonomously in the F- cell.
Termination: Pilus retracts, both donor and recipient cell resumes normal growth and
activities.
