Exam #8 Flashcards
The nitrogenous base adenine is found in all members of which group?
- Proteins, triglycerides, and testosterone
- proteins, ATP and DNA
- ATP, RNA, and DNA
ATP, RNA, and DNA
A particular triplet of bases in the template strand of DNA is 5’ AGT 3’. The corresponding codon for the mRNA transcribed is
- 3’ ACU 5’
- 3’ UCA 5’
- 3’ UGA 5’
3’ UCA 5’
The genetic code is essentially the same for all organisms. From this, one can logically assume which of the following?
- DNA was the first genetic material
- A gene from an organism can theoretically be expressed by any other organisms.
- All organisms have experienced convergent evolution
A gene from an organism can theoretically be expressed by any other organism.
Which of the following provided some evidence that RNA probably evolved before DNA?
- DNA polymerase uses primer, usually made of RNA
- DNA polymerases has proofreading function
- RNA polymerase uses DNA as a template
DNA polymerase uses primer, usually made of RNA.
Which of the following does not occur in prokaryotic gene expression, but does occur in eukaryotic gene expression?
- A poly- A tail is added to the 3’ end of an mRNA and a cap is added to the 5’ end
- mRNA, tRNA, and rRNA are transcribed
- RNA polymerase requires a primer to elongate the molecule
A poly - A tail is added to the 3’ end of an mRNA and a cap is added to the 5’ end.
In eukaryotes there are several different types of RNA polymerase. Which type is involved in transcription of mRNA for a glob in protein?
- RNA polymerase II
- ligase
- Primase
RNA polymerase II
Transcription in eukaryotes requires which of the following in addition to RNA polymerase?
- ribosomes and tRNA
- several transcription factors
- amino acid- tRNA synthetase
- aminoacyl- tRNA synthetase
Several transcription factors
A part of the promoter, called the TATA box, is said to be highly conserved in evolution. Which of the following might this illustrate ?
- The sequence does not mutate
- Any mutation in the sequence is selected against.
- The sequence is transcribed at the start of every gene
Any mutation in the sequence is selected against.
In order for a eukaryotic gene to be engineered into a bacterial colony to be expressed, what must be included in addition to the coding exo said of the genes?
- eukaryotic rRNAs
- a bacterial promoter sequence
- the introns
A bacterial promoter sequence
RNA polymerase moves in which direction along the DNA?
- 3’ to 5’ along the no template strand
- 3’ to 5’ along the template strand
- 5’ to 3’ along whichever strand it’s on
3’ to 5’ along the template strand
What is a ribozyme?
- an RNA with enzymatic activity
- an enzyme that uses RNA as a substrate
- an enzyme that synthesizes RNA primers during DNA replication
An RNA with enzymatic activity
During splicing, which molecular component of the spliceosome catalyzes the excision reaction?
- lipid
- RNA
- DNA
RNA
Which of the following experimental procedures is most likely to hasten mRNA degradation in a eukaryotic cell?
- removal of one or more exons
- methylation of his tones
- removal of the 5’ cap
Removal of the 5’ cap
A particular triplet of bases in the coding sequence of DNA is AAA The anticodon on the tRNA that binds the mRNA codon is ?
- UUU
- CCC
- AAA
UUU
Accuracy in the translation of mRNA into the primary structure of a polypeptide depends on specificity in the
- bonding of the anticodon to the codon
- bonding of the anticodon to the codon and the attachment of amino acids to tRNAs
- binding of ribosomes to mRNA
Bonding of the anticodon to the codon and the attachment of amino acids to tRNAs
The role of a metabolite that controls a repressive operon is to
- bind to the repressor protein and activate it
- bind to the repressor protein and inactivate it
- increase the production of inactive repressor proteins
Bind to the repressor protein and activate it.
The tryptophan operon is a repressive operon that is
- turned off whenever tryptophan is added to the growth medium
- turned on only when tryptophan is present in the growth medium
- permanently turned on
Turned off whenever tryptophan is added to the growth medium.
Which of the following is a protein produced by a regulatory gene?
- inducer
- operon
- repressor
Repressor
A lack of which molecule would result in the cell’s inability to “turn off “ gene?
- inducer
- Corepressor
- operon
Corepressor
Most repressor proteins are allosteric. Which of the following binds with the repressor to alter its conformation?
- promoter
- cAMP
- inducer
Inducer
The lactose operon is likely to be transcribed when
- the cyclic AMP and lactose levels are both high within the cell
- the cyclic AMP levels are low
- there is more glucose in the cell than lactose
The cyclic AMP and lactose levels are both high within the cell.
Altering patterns of gene expression would most likely serve the organism’s survival in which of the following ways?
- allowing each gene to be expressed an equal number of times
- allowing environmental changes to alter the prokaryote’s genome
- allowing the organism to adjust to changes in environmental condition
Allowing the organism to adjust to changers in environmental conditions
In responses to chemical signals, prokaryotes can do which of the following ?
- inactivate their mRNA molecules
- turn off translation of their mRNA
- alter the level of production of various enzymes
Alter the level of production in various enzymes
If you were to observe the activity of methylated DNA, you would expect it to
- be replicating nearly continuously
- be very actively transcribed and translated
- have turned off or slowed down the process of transaction
Have turned off or slowed down the process of transcription
Genomic imprinting, DNA methylation, and Histone acetylation are all example of
- translocation
- epigenetic phenomena
- genetic mutation
Epigenetic phenomena
Two potential devices that eukaryotic cells use to regulate transcription are
- DNA methylation and Histone modification
- DNA methylation and Histone amplification
- DNA acetylation and methylation
DNA methylation and Histone modification
Steroid hormones produce their effects in cells by
- binding to intracellular receptors and promoting transcription of specific genes
- activating key enzymes in metabolic pathways
- activating translocation of certain mRNAs
Binding to intracellular receptors and promoting transcription of specific genes
The phenomenon in which RNA molecules in a cell are destroyed if they have a sequence complementary to an introduced double- stranded RNA is called
- RNA obstruction
- RNA interference
- RNA disposal
RNA interference
In a genome- wide expression study using a DNA microarray assay, each well is used to dectect the
- location of a protein produced by a cell
- fate of proteins produced by a cell
- expression of specific gene by a cell
Expression of a specific gene by a cell
Which one of the following techniques involved reverse transcriptase, PCR amplification, and tell electrophoresis?
- nucleic acid hybridization
- DNA microarray assays
- RT- PCR
RT-PCR
