Bread mold can grow in a minimal medium without supplements (wild type) while certain mutated strains (mutants) can only grow in a minimal medium that is supplemented with specific intermediates found in the following metabolic pathway for arginine synthesis:
minimal ------> ornithine -------> citrulline ------> arginine, where enzyme 1 converts the precursor to ornithine, enzyme 2 converts ornithine to citrulline, and enzyme 3 converts citrulline to arginine.
A strain that can grow in a minimal medium containing arginine, but NOT in a minimal medium containing citrulline or ornithine would have a mutation in the gene that encodes for
enzyme 3.
Bread mold can grow in a minimal medium without supplements (wild type) while certain mutated strains (mutants) can only grow in a minimal medium that is supplemented with specific intermediates found in the following metabolic pathway for arginine synthesis:
minimal ------> ornithine -------> citrulline ------> arginine, where enzyme 1 converts the precursor to ornithine, enzyme 2 converts ornithine to citrulline, and enzyme 3 converts citrulline to arginine.
Which of the following would be true of a strain that can grow in minimal medium containing ornithine, citrulline, or arginine, but not in minimal medium alone?
The strain would have a mutation in the gene that encodes enzyme 1.
The process that produces mRNA from DNA is called
transcription.
The processes of transcription and translation are collectively known as
gene expression.
________ is directly produced from the transcription of a eukaryotic gene.
pre-mRNA
________ is to transcription as ________ are to translation?
RNA polymerase; ribosomes
A(n) ______ is an organized unit of DNA sequences that enables a segment of DNA to be transcribed into RNA and ultimately results in the formation of a functional product.
gene
Which of the following are products of nonstructural genes, and are therefore never translated?
transfer RNA and ribosomal RNA
Transcription begins near a site in the DNA called the ______, while the terminator specifies the end of transcription.
promoter
Which of the following regions of a structural gene contains the information that specifies an amino acid sequence?
transcribed region
Which of the following statements about RNA polymerase in bacteria is INCORRECT?
It catalyzes the addition of nucleotides to the 5end of a growing RNA strand.
If a DNA template strand has a sequence of 3 TACAATGTAGCC 5, then the RNA produced from it will be which sequence?
5'AUGUUACAUCGG3'
Which of the following basic features of transcription is NOT shared by both prokaryotes and eukaryotes?
The complexity of protein components involved in transcription is similar for both prokaryotes and eukaryotes.
Which of the following proteins is involved in synthesizing messenger RNA in eukaryotes?
RNA polymerase II
Which protein influences the ability of RNA polymerase to transcribe genes?
transcription factors
Intervening sequences that are transcribed, but not translated into protein are called
introns.
Which of the following would occur if a cell's splicesomes were mutated so they no longer functioned normally?
Introns would remain in the mature mRNA
Which of the following statements about RNA processing in eukaryotes is INCORRECT?
Introns are simply excised out of pre-mRNA to produce the mature mRNA
________ enables a single gene to encode two or more polypeptides that are different in their amino acid sequence.
Alternative splicing
Which of the following molecule(s) exhibits self-splicing?
rRNA and tRNA