Viruses
This is the phage replicative cycle that results in the death of the host cell.
Lytic
Adenine is what type of nucleotide base?
Purine
Insertions and deletions can result in this type of mutation.
Frameshift
What is the role of the molecule tryptophan in the trp operon?
Corepressor
What enzyme is used to create bonds between a DNA insert and a cloning vector?
Ligase
When phage DNA is integrated into a bacterial chromosome, it is referred to as ______.
Prophage
These proteins prevent the separated DNA strands from rejoining.
Single-strand binding proteins
What provides the energy for the assembly of the small and large ribosomal subunits?
GTP
This type of RNA can result in the degradation of mRNA or the blocking of translation of the mRNA.
siRNA or microRNA
How are reporter genes used in biotech? Give an example.
Indicates when (or where) another gene of interest might be expressed by displaying some sort of visual cue (examples: GFP, luciferase)
What is a prion and how does it function?
Infectious protein (misfolded protein causing other proteins to misfold → aggregates → neurodegeneration)
What is a lagging strand and why does it exist during DNA replication?
DNA can only be synthesized by adding on nucleotides onto the 3’ end of the growing strand → does small fragments at a time that go away from replication fork → ligase puts them together.
What is the role of the polyadenylation signal sequence during transcription in Eukaryotes?
Signal the recruitment of enzymes to cut free the mRNA transcript and signal the end of transcription.
Explain how transcription is regulated in Eukaryotes.
Specific proteins bind to control elements (proximal or distal) in the enhancer region which signals the recruitment of general transcription factors, DNA bending protein, and RNA polymerase, and bends the DNA so that the enhancer comes in contact with the transcription initiation complex at the promoter region to start transcription.
What are iPS cells and how are they made?
Take a differentiated cell, and introduce genes using a retrovirus that reprograms the cell back to an embryonic stem cell like state
Why do viral envelopes help prevent detection of the virus by the host immune system?
Viral envelope made of the same material as the host cell so the immune system doesn’t recognize it as foreign.
This enzyme removes damaged DNA such as Thymine dimers during excision repair.
Nuclease
During elongation of the polypeptide chain during translation, amino acids are added to which end of the growing chain?
Carboxyl end or C-terminus
How do E. coli in the gut respond to an influx of lactose, when glucose is low and when glucose is high?
Glucose is low, cAMP is high, binds to CAP and activates it and increases polymerase affinity to the promotor and make it more likely to synthesize the enzymes that break down lactose (allolactose is acting as an inducer and preventing the repressor from binding to the operator). When glucose is high, polymerase will bind at a much lower rate even when the operator is on.
Explain the process of somatic cell nuclear transfer in cloning.
Remove the nucleus from a somatic cell and insert it into an enucleated egg. Zap, let grow to blastocyst stage, insert into surrogate, and offspring will be genetically identical to the nucleus donor.