genetics final (test 2 questions)
Which of the following is widely used as a vector plant transgenics?
Agrobacterium plasmid
The process of translation, whether in prokaryotes or eukaryotes, requires tRNAs, amino acids, ribosomal subunits, and which of the following?
Elongation factors plus GTP
For any organism it is important for genes to be expressed in the correct place, at the correct time, but the amount (level) of expression doesn't matter.
False
Suppose that a mutation occurs in a prokaryote that removes most of the 5' UTR. What would be the consequence of this?
Removal of the 5' UTR will result in incorrect binding of the mRNA to the ribosome
With respect to the lac operon, which of the following statements is most true of glucose?
The presence of glucose inactivates the positive control molecule
A bacterial operon is responsible for the production of important enzymes. The product of a different gene 'R' is involved in regulation of this operon. To figure out how this operon works, you create a strain of bacteria where the R gene is not functional. No expression of the operon occurs in this strain. From this information, you can conclude that:
The product of the R gene is a positive control
Incremental changes in the amount of expression in eukaryotes can be regulated by changing the amount or activation of
Transcriptional Activator Proteins, transcription factors, and coactivators
To generate herbicide resistance in crop plants, a fusion gene construct is first created that includes a viral promoter to control the EPSP synthase gene expression
True
Addition of acetyl (CH3CO) or methyl (CH3) groups to histone proteins by the cell results in:
allowing expression to occur
When the ribosome reaches a stop codon on the mRNA, no corresponding tRNA enters the ribosome. If the translation reaction were to be experimentally stopped immediately as the stop codon is reached, which would you be able to isolate?
an assembled ribosome with a polypeptide attached to the tRNA in the P site
A commonly used antibiotic works by preventing charged methionine tRNA from interacting with the ribosome or mRNA. Given this information you can conclude that this antibiotic most likely disrupts the function of
an initiation factor
Transcription factors
are necessary for RNA polymerase to bind to the promoter in eukaryotes
In certain situations, methylation patterns that alter levels of expression levels are thought to
be passed on from parent to offspring, be induced or removed in offspring due to maternal diet, be induced or removed in offspring due to maternal behavior
where parts of the basal transcription apparatus forms
core promoter
With respect to regulation of the trp operon, what is the appropriate term for the amino acid tryptophan?
corepressor
several can be associated with a single gene, acts as a signal for binding of transcriptional activator proteins
enhancer
The research presented by Jim Fallon on the genetics of sociopathy an serial killers is an example of:
genotype x environment interaction
When siRNAs are present, the rate of degradation of targeted mRNAs ______ and the rate of corresponding protein production___________
increases, decreases
Addition of methyl (CH3) groups to cytosine of the DNA molecule results in:
inhibiting expression
directly involved in the tertiary structure of proteins:
interaction of hydrophobic amino acids, cysteine, R-groups, and ionic bonds
When cloning genes into plasmids, it is important to treat both the plasmid and the gene with the same restriction enzyme because
it ensures that the gene and plasmid will have complementary single strand ends
A mutation in the repressor associated with the lac operon which changes the allosteric site preventing binding of the inducer to the repressor should result in
lack of expression or reduced expression of the lac operon genes under all circumstances
Which of the following is the most correct order of events during the initiation phase of translation?
mRNA binds to the small ribosomal subunit, the charged initiator (met) tRNA binds to the mRNA/ribosome complex, large ribosomal subunit binds, initiation factors release
The sequence below is from the coding region of a template strand of DNA. What is the amino acid sequence of the protein it codes for? 3'-TACCACGACTTCACT-5'
met-val-leu-lys
Which of the following are NOT directly involved in the tertiary structure of proteins?
peptide bonds
You discover an operon that controls the production of an important bacterial enzyme. Under most conditions this gene is expressed. However, when you add the right chemical to the bacterial environment expression stops. This operon is most likely
repressible
A tRNA anticodon is 3'-UCG-5' . What amino acid does it carry?
ser
Transcription of the structural genes in an inducible operon:
starts when the enzyme pathway's substrate is present
A mutation has occurred in a tRNA molecule that results in the attachment of the wrong amino acid binding site for that tRNA. This mutation most likely affected the _____
the "other" steps and loops
Which of the following is the earliest event to take place in the translation process of eukaryotes?
the small subunit of the ribosome recognizes and attaches to the 5' UTR/5'cap of mRNA
Which of the following does NOT occur during the termination phase of translation?
the tRNA with the stop anticodon and stop amino acid enters the A site.
Plasmids and phages are important in recombinant DNA technology because
they can be replicated in host cells, they are a vehicle for the insertion of foreign genes into other organisms, they will incorporate foreign dna, and they can be engineered to promote expression of foreign genes in the host cell
In which of the following situations would the cell use an siRNA/RISC complex?
to rid the cell of mRNAs produced before translation can occur
The trp operon is repressible, meaning that it is____
turned off when tryptophan is present