DNA Cloning

Concept: Transformation and Restriction Endonucleases


Concept: Recombinant Plasmids


Concept: Transformation and Antibiotic Resistance


DNA Cloning Additional Practice Problems

During the procedure to form recombinant DNA molecules, the purpose of the cell transformation step is to

A. use the transformed cells to combine vector and source DNA in order to form recombinant molecules.

B. use the transformed cells as a source of DNA ligase to form recombinant molecules.

C. use the transformed cells to cut the DNA at specific sites to generate fragments.

D. all the above

E. None of the above

Watch Solution

Name the restriction endonuclease that cuts at the following sites. Indicate whether it cuts in a blunt or staggered manner.





Watch Solution

What is recombinant DNA technology? What are the safety issues related to recombinant DNA technology?

Watch Solution

You digest DNA from the frog Xenopus laevis with HindIII that produces sticky DNA ends. You can ligate your DNA to : (check all that apply)

A. HindIII sticky DNA ends from Xenopus laevis

B. EcoRI sticky DNA ends from Xenopus laevis

C. blunt DNA ends from bacteria

D. HindIII sticky DNA ends from bacteria

Watch Solution

Which ofthe following is a palindromic restriction site?

A. 5' - ACGGCA - 3'

B. 5' - TGCGCC - 3'

C. 5' - AAGGTT - 3'

D. 5' - ACGCGT - 3'

E. 5' - GCAGCA - 3'

Watch Solution

Jason is setting up a reaction with the restriction endonuclease EcoRI. The concentration of the EcoRI enzyme solution is 20,000 units/mL. Jason mixes the following in a test tube:

4 uL dsDNA, 14 uL buffer, 2 uL EcoRI

What is the final concentration of EcoRI enzyme in Jason's reaction?

A. 2,222 units/mL

B. 2,857 units/mL

C. 2,000 units/mL

D. 200,000 units/mL

Watch Solution

How is a gene for a particular protein inserted into a plasmid?

Watch Solution

What is a restriction enzyme? What role do they play in biotechnology experiments?

Watch Solution

What is Recombinant DNA?

Watch Solution

Restriction enzymes cut DNA at random sites.


b. False

Watch Solution

"Sticky ends" are

a. single-stranded DNA sequences that are generated by staggered cuts.

b. double-stranded DNA sequences that are generated by staggered cuts.

c. single-stranded DNA sequences that are generated by blunt cuts.

d. double-stranded DNA sequences that are generated by blunt cuts.


Watch Solution

The function of the enzyme ligase is to

a. add new DNA to the plasmid.

b. remove DNA from the plasmid.

c. form covalent bonds between cloned gene and plasmid.

d. repair damaged DNA.

e. purify the plasmid DNA.

Watch Solution

Arrange the following events in the proper sequence for gene cloning.
1 = Incorporate gene into bacterial plasmid
2 = Isolate DNA from organism containing desired gene
3 = Incorporate cloned gene into bacterial cells
4 = Fragment DNA with restriction enzyme

a. 1, 2, 3, 4

b. 2, 1, 4, 3 

c. 2, 3, 4, 1 

d. 2, 4, 1, 3 

e. 2, 4, 3, 1


Watch Solution

Restriction enzymes cut only at specific sites and therefore are not useful for genetic engineering.

a. True

b. False

Watch Solution

Human DNA cut with restriction enzyme A can be joined to

a. human DNA cut with restriction enzyme B.

b. human DNA that is uncut.

c. bacterial DNA cut with restriction enzyme A.

d. bacterial DNA that is uncut.

e. none of the above

Watch Solution

The single-stranded ends of DNA molecules can be joined together by

a. restriction endonucleases.

b. DNA ligase.

c. DNA polymerase.

d. primase.

e. helicase.

Watch Solution

The single-stranded but complementary ends of the two DNA molecules cleaved by the restriction enzyme _____.

a. are called "sticky ends"

b. can bind by complementary base pairing

c. facilitate the insertion of foreign DNA into vector DNA

d.  All of the above

Watch Solution

The foreign DNA is sealed into the opening created by the restriction enzyme by _____.

a. DNA polymerase

b. DNA repair enzymes

c. DNA ligase

d. helicase

Watch Solution

The plasmid DNA is cleaved by _____.

a. DNA ligase

b. DNA polymerase

c. a restriction enzyme

d. helicase


Watch Solution

Small accessory rings of DNA are called _____.

a. recombinant DNA

b. plasmids

c. clones

d. transposons

Watch Solution

The process used to rapidly produce DNA sequences of interest is DNA sequencing. 

a. True

b. False

Watch Solution