Bacterial Genetics

Question 1

Transformation

Answer 1

Ability to take up DNA from the environment (competence)

Question 2

Conjugation

Answer 2

Genes in one bacterial plasmid (F+) sent to bacteria without this plasmid (F-). Transfer occurs with a sex pilus.

Also, F+ plasmid can be incorporated into bacterial chromosomal DNA (Hfr). Then when the bacterium replicates, the new daughters cells will have the genes in the plasmid (plasmids are not normally replicated in bacterial reproduction)

Question 3

Transposition

Answer 3

Segments of DNA are excised and inserted from location to another. Sometimes the chromosomal genes are transferred to the plasmid and visa versa

Question 4

Generalized Transduction

Answer 4

Lytic phage infects a bacterium and new viral proteins are made. Bacterial proteins get packaged in with the new viral proteins and get transferred along with the virus to a new bacterium.

Question 5

Specialized Transduction

Answer 5

Lysogenic phage infects a bacterium, viral DNA is inserted into host bacteria DNA. Once lytic phase begins the viral DNA is cleaved along with some bacterial DNA and transferred to another bacterium.

Question 6

Name the 4 phases of a bacterial growth curve

Answer 6

Lag Phase: metabolism but no growth or division
Exponential Phase: rapid cell devision
Stationary Phase: nutrients start to be depleted and balance out the growth
Death Phase: nutrients depleted everything dies