Biotechnology Tools And Techniques

Question 1

Recombinant DNA?

Answer 1

A fragment of DNA composed of sequence at least 2 different sources

Question 2

Restriction endonucleases (restriction enzyme), what do they do?

Answer 2

-recognize specific base pair sequences in DNA and then cut the double standard DNA at those sites

Question 3

Restriction endonucleases (restriction enzyme), how do they do the cutting?

Answer 3

• Binds to recognition site
• hydrolysis reaction to disrupt the phosphodiester bonds
• hydrogen bonds between bases are disrupted
• result = two fragments of DNA

Question 4

Restriction endonucleases (restriction enzyme), function?

Answer 4

• rudimentary immune system in bacteria
• cleaves virus DNA into fragment
• host DNA is methylated RE knows not to cleave it

Question 5

Recognition site characteristics?

Answer 5

Sequence recognized by the enzyme

• specific to each different RE
• 8 base pair RS = too long, 6 base pair RS = ideal
• palindromic can read the same backwards and forwards

Question 6

Sticky ends

Answer 6

-Cleavage produces an overhang
-sticky ends are more useful
If two fragments are cut with the same RE they will have complementary sticky ends
These fragments can be joined by another enzyme

Question 7

Blunt ends

Answer 7

No overhang

Question 8

Methylases

Answer 8

Enzymes
Add methane groups to recognition site
Prevents RE from cleaving to DNA
FUNCTION: protects host DNA from own RE’s

Question 9

Ligases

Answer 9

Joins sugar and phosphate backbones of DNA fragments

Can be used to join fragments that have complementary ends via phosphodiester bonds

Question 10

What is biotechnology?

Answer 10

Applied biology
Uses living organisms and their components to create “bio products”
Involves manipulation of DNA