Check Your Understanding: Ligation & Transformation

1. In insertional inactivation, if foreign DNA is inserted, the beta galactosidase marker is

• inactivated, and the colonies remain white

• inactivated, and the colonies turn blue

• activated, and the colonies remain white

• activated, and the colonies turn blue

2) If host cells are ampicillin sensitive and are plated on a medium containing ampicillin,

• only cells that have not taken up the ampicillin resistant plasmid can grow

• only cells that have taken up the ampicillin resistant plasmid can grow

• all cells will grow

• ampicillin is inactivated

3) The lac z gene marker codes for

• b galactosidase, which catalyses breakdown of x-gal

• b galactosidase, which makes x-gal resistant to splitting

• ampicillin resistance

• white colonies

When foreign DNA and plasmid are both cut with the same restriction enzyme and mixed together, all molecules will form recombinants.

• True

• False

When beta galactosidase cleaves x-gal, white colonies result.

• True

• False

Draw a diagram to show the structure of a plasmid. 

(i) Label the important parts of the plasmid.

(ii) Briefly state the function of each part.

Summarise the brief steps to produce a recombinant plasmid.