Lecture 9 Notes

Question 1

genes are on chromosomes

Answer 1

recombination occurs between genes

Question 2

can recombination occur within a gene?

Answer 2

recombination within a gene would be extremely rare

Question 3

lytic lifestyle of T4 phage

Answer 3

1. phage injects its DNA into host cell
2. phage proteins synthesized; DNA replicated. Host chromosome degraded
3. assembly of phages within host cell
4. lysis of host cell

Question 4

the E. coli K host can be used to detect wild type phage in a population of rll mutants. Is this a screen or selection?

Answer 4

selection

Question 5

complementation test

Answer 5

• occurs between mutations on separate genes
• no complementation: no cell lysis, no phage progeny
• complementation: cell lysis, phage progeny

Question 6

complementation group

Answer 6

• coinfections with two mutants

- do not complement each other

Question 7

linked mutations

Answer 7

mutations can be as close as nearby base pairs

Question 8

Is the approach used to isolate auxotroph mutants a screen or selection?

Answer 8

screen