[13] Restriction Enzymes and Cloning Flashcards
What are restriction enzymes?
Proteins that can cut DNA at specific sequences.
What is the purpose of restriction enzymes in nature?
They protect bacteria from invading viruses by cutting the virus’s DNA into pieces.
How are restriction enzymes used in genetic engineering?
They are used to cut DNA at specific points to allow the insertion of new genes.
What is DNA cloning?
The process of making multiple, identical copies of a particular piece of DNA.
How are restriction enzymes used in DNA cloning?
They are used to cut both the DNA to be copied and the DNA of the vector (like a plasmid) that will carry the DNA.
What is a plasmid?
A small, circular piece of DNA found in bacteria that can replicate independently of the chromosomal DNA.
Why are plasmids used in DNA cloning?
Plasmids can be easily manipulated and introduced into bacterial cells, allowing the copied DNA to be reproduced when the bacteria multiply.
What is a vector in the context of DNA cloning?
A carrier DNA molecule into which the DNA fragment to be cloned can be inserted.
What does “recombinant DNA” mean?
DNA that has been formed by combining segments from different sources.
How is recombinant DNA created?
By using restriction enzymes to cut DNA from different sources and then ligase enzyme to join the fragments together.
What is a “sticky end” in the context of restriction enzymes?
An overhang of unpaired bases on a DNA strand cut by a restriction enzyme.
What is the significance of “sticky ends”?
They allow the DNA to be easily reattached to another piece of DNA with complementary “sticky ends”.
What is DNA ligase?
An enzyme that can join together two DNA fragments.
How is DNA ligase used in DNA cloning?
It is used to join the “sticky ends” of DNA fragments to create a continuous DNA molecule.
What is transformation in the context of DNA cloning?
The process of introducing a plasmid into a bacterial cell.
