Recombinant DNA Technology

Question 1

What is recombinant DNA?

Answer 1

DNA from different sources that has been fused together

Question 2

Why use recombinant DNA (4 reasons)?

Answer 2

• Agriculture - GE crops
• Genetic engineering
• Basic science to study genes and proteins
• Pharmaceuticals

Question 3

What are restriction enzymes?

Answer 3

Endonucleases that recognize and cut specific, short palindromic sequences

Question 4

Where do restriction enzymes come from?

Answer 4

Bacteria, they are named after the species from which they were isolated from

Question 5

Why do bacteria have restriction enzymes? How do they protect their own DNA from being cut up by their own enzymes?

Answer 5

They had evolved to protect bacteria from bacteriophages by cutting up the invading DNA and making it nonfunctional. Bacteria methylate their DNA at the recognition sites so they don’t get cut by the enzymes

Question 6

How can we use restriction enzymes for genetic engineering?

Answer 6

They can leave sticky ends when the DNA is cut, which will complementary base pair to the complementary sequence. We can have a piece of foreign DNA cut by the same enzyme, and it can also complementary base pair to the sticky overhang. Then we can add DNA ligase to seal the backbone and create a recombinant DNA molecule

Question 7

How does circular DNA travel through a gel compared to a linear piece of DNA that is the same size?

Answer 7

Slower

Question 8

How does supercoiled DNA travel through a gel compared to a linear piece of DNA that is the same size?

Answer 8

Faster

Question 9

What is molecular cloning?

Answer 9

Using bacteria to replicate a recombinant plasmid then isolating it from the culture