DNA/RNA Flashcards
What are restriction enzymes?
DNA cutting enzymes that digest DNA into small fragments.
How do restriction enzymes cut DNA?
They cut at specific sites by recognizing palindromic sequences.
What is a palindrome in the context of DNA?
A sequence that reads the same forwards and backwards on two strands, e.g., 5’-GAATTC-3’.
What is the role of DNA ligase?
It repairs DNA backbones by joining DNA with compatible sticky ends.
What is a plasmid?
A circular form of self-replicating DNA used to carry and clone other pieces of DNA.
What is the origin of replication?
A DNA sequence in a plasmid where replication begins (self replicating)
What are vectors in molecular biology?
Pieces of DNA, like plasmids, that can accept, carry, and replicate other DNA.
What is recombinant DNA?
DNA from two different sources that has been recombined into a single molecule.
Why create recombinant DNA?
To study or manipulate individual genes and introduce new proteins into cells.
What is molecular cloning?
A technique to make copies of specific DNA fragments for detailed study.
What does it mean when bacteria are transformed?
They have taken up foreign DNA under the right conditions.
What are selectable marker genes?
Genes that indicate which bacteria contain plasmids with foreign DNA.
What is a multiple cloning site (MCS)?
A DNA segment with many cut sites for inserting new DNA.
What is the function of the ampR gene?
It provides antibiotic resistance by producing an enzyme that breaks down antibiotics.
What is the purpose of colony selection?
To identify bacteria that have taken up plasmids with desired foreign DNA.
What is the function of the LacZ enzyme?
It metabolizes lactose and X-gal, turning bacteria blue when functional.
What happens during insertional inactivation?
Inserting foreign DNA into the LacZ gene disrupts its function, preventing blue coloration.
What is a genomic library?
A collection of all bacteria or plasmids containing DNA fragments for genome study.
What is the first step in creating a genomic library?
Cut genomic DNA with restriction enzymes.
How is plasmid DNA purified?
By breaking open cells, removing debris, and separating plasmid DNA using a column.
What is gel electrophoresis used for?
To measure the size of DNA fragments based on their movement through a gel.
What are open reading frames (ORFs)?
Stretches of DNA that could code for a protein, starting with a start codon and ending with a stop codon.
