Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
27 Cards in this Set
- Front
- Back
|
Properites of a cloning vector include...
|
1. Several Restriction sites
2. Should carry a selectable maker 3. Vector and inserted DNA should be easy to isolate from host cell |
|
|
What is one example of a cloning vector?
|
A Plasmid
|
|
|
What is a Plasmid?
|
Double stranded DNA molecules that replicate autonomously in bacterial cells
|
|
|
What is a restriction fragment length polymorphism (RFLP)?
|
A region of DNA that varies in restriction enzyme cutting sites from one individual to another.
Can be used to identify genetic diseases. |
|
|
What is PCR?
|
Polymerase chain reaction
|
|
|
What are the advantages to using PCR compared to other techniques?
|
1. DNA can be copied without a host cell.
2. Only a small amount of DNA is needed. |
|
|
What is needed to for PCR to occur?
|
1. DNA Polymerase
2. Mg2+ ions 3. The four deoxonucleoside phosphates. 4. DNA primers |
|
|
What specific polymerase is used?
|
Taq polymerase from the bacterium Thermos Aquaticus.
|
|
|
What are the steps in PCR?
|
1. Denaturation
2. Annealing 3. Extension (3 steps equal one cycle) |
|
|
What are the disadvantages to using PCR?
|
1. Knowledge required about target DNA sequence in order to make primers.
2. Contamination can occur very easily. |
|
|
Where is PCR most extensively used?
|
Forensics
Paleontology |
|
|
What are the properties of the genetic code?
|
1. Linear
2. Triplet code 3. Unambiguous 4. Degenerate 5. commaless 6. non-overlapping 7. Nearly universal 8. One stop and three start codons |
|
|
With respect to the genetic code what does unambiguous mean?
|
Each codon specifies one amino acid.
|
|
|
What is the start codon?
|
AUG
|
|
|
What amino acid does the start codon code for?
|
Methionine
|
|
|
With respect to the genetic code what does degeneracy mean?
|
many amino acids (18 out of 20) are specified by more than one codon.
|
|
|
What does the wobble hypothesis state?
|
The first two letters of a codon are more critical than the third.
|
|
|
tRNA has what distinctive nucleotide base?
|
Inosine, which can pair with A, U, or, C.
|
|
|
How many codons specify the 20 different amino acids?
|
61
|
|
|
How many tRNA's are needed to pair with the 61 mRNA codons?
|
30
|
|
|
What is a nonsense mutation?
|
A mutation that changes a codon into a termination codon that causes premature termination and a nonfunctional protein.
|
|
|
How many strands of the DNA molecule are involved in the transcription of a single gene?
|
Only 1, the template strand.
|
|
|
What is meant by chromatin remodeling?
|
In Eukaryotes chromatin fiber needs to be uncoiled and DNA made accessible to RNA polymerase and other regulatory proteins.
|
|
|
What are enhancers and silencers?
|
In eukaryotes, gene sequences that increase or decrease the level of transcription.
|
|
|
What are transcription factors?
|
Proteins transcribed and translated from other genes that affect gene expression.
These are trans-acting. |
|
|
What is a general transcription factor?
|
Proteins that need to be present so that RNA polymerase II can bind to promoter sites and initiate transcription
|
|
|
What is a specific transcription factor?
|
Proteins that affect the rate and efficiency of transcription.
|
