test 1 BIO 1a03 Exam 2026 Questions and
Answers
Central Dogma - Correct answer-theory that states that, in cells, information only
flows from DNA to RNA to proteins
what enzyme is used to transcribe DNA and describe the process - Correct answer-
RNA polymerase attaches to specific promoter regions its these promoter regions
which identifies the starting point,
describe the DNA and RNA directionality and how the direction followed by RNA
polymerase - Correct answer-the 5' end has the 5'phosphate on a nucleotide the
other end is the 3' OH group of a nucleotide
-traditionally read from 5' to 3'
- the RNA polymerase goes in a 3' to 5' direction
-synthesizing a molecule from the 5' to 3'
-
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,what are the stop and start regions of DNA called - Correct answer-promoter (start)
and stop regions
why does RNA polymerase need Sigma factors - Correct answer-sigma factors
facilitate binding to the promoter region of the DNA
what do holoenzymes do - Correct answer-they can bind and unwind the double
stranded DNA helix to allow for transcription
describe the process of transcription - Correct answer--RNA polymerase binds to a
promoter region
- RNA polymerase begins to catalyze the production of antiparallel RNA that is
complementary to the template strand creating an RNA-DNA duplex
-template is read in 3' to 5' but the RNA is synthesized from 5' to 3'
why do ribonucleosides triphosphates pair with template DNA - Correct answer-
The phosphate bond is used to drive the reaction to create a phosphodiester bond
between the incoming nucleotide and the RNA transcript
what are the two types of terminator sequences - Correct answer--Rho-independent
terminator sequences they fold back on themselves to form a G-C hairpin loop and
release the mRNA transcript
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,- Rho-dependent terminator sequences use specific rho factors which bind and use
ATP to move along the formed RNA transcript and destabilases the interaction
between RNA and DNA and releases of the complex
What are transcription factors? - Correct answer-mediate the binding of RNA
polymerase and the initiation of transcription
different types of RNA polymerase and their function - Correct answer--RNA
polymerase 1 and 3 both transcribe structural non coding RNA, 1 focuses on
Ribosomal RNA while 3 focuses on transfer RNA
-RNA polymerase 2 that transcribes the messenger RNA
identify and describe some post transcriptional modifications that occur at the end
of primary mRNA transcript - Correct answer--5' cap and 3' poly tail
-these modification are these to ensure the export of mRNA from the nucleus and
protect against ribonuclease enzymes which target phosphodiester bonds
Describe the 5' cap - Correct answer-7-methylguanosine is attached through a 5'-5'
triphosphate linkage
what are exons - Correct answer-sequences of mRNA that are needed for coding
the sequence of amino acids in the protien
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, what are introns - Correct answer-the intervening sequences that are transcribed
but not translated into protein
what happens if RNA splicing does not occur - Correct answer-the protein may not
have the correct sequences of amino acids
Describe RNA splicing - Correct answer-occurs at nucleotide sequences of introns
and is catalyzed by large molecules called spliceosomes made up of snRNP
-RNA spliceosomes can recognize and from base pairings with nucleotides at
designated splice sites which then allows for a OH group to attack and form a new
phosphodiester bond
What do nuclear pores do? - Correct answer-allow nuclear membrane to selectively
move molecules in and out of nucleus
What are frameshift mutations? - Correct answer-One or two base pair is added or
deleted, everything shifts, most of the amino acids will change.
what happens when three nucleotides are removed - Correct answer--no change in
the reading frame
-the identity of the protein is maintained
Proteins are synthesized from - Correct answer-ribosomes
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Answers
Central Dogma - Correct answer-theory that states that, in cells, information only
flows from DNA to RNA to proteins
what enzyme is used to transcribe DNA and describe the process - Correct answer-
RNA polymerase attaches to specific promoter regions its these promoter regions
which identifies the starting point,
describe the DNA and RNA directionality and how the direction followed by RNA
polymerase - Correct answer-the 5' end has the 5'phosphate on a nucleotide the
other end is the 3' OH group of a nucleotide
-traditionally read from 5' to 3'
- the RNA polymerase goes in a 3' to 5' direction
-synthesizing a molecule from the 5' to 3'
-
©COPYRIGHT 2025, ALL RIGHTS RESERVE 1
,what are the stop and start regions of DNA called - Correct answer-promoter (start)
and stop regions
why does RNA polymerase need Sigma factors - Correct answer-sigma factors
facilitate binding to the promoter region of the DNA
what do holoenzymes do - Correct answer-they can bind and unwind the double
stranded DNA helix to allow for transcription
describe the process of transcription - Correct answer--RNA polymerase binds to a
promoter region
- RNA polymerase begins to catalyze the production of antiparallel RNA that is
complementary to the template strand creating an RNA-DNA duplex
-template is read in 3' to 5' but the RNA is synthesized from 5' to 3'
why do ribonucleosides triphosphates pair with template DNA - Correct answer-
The phosphate bond is used to drive the reaction to create a phosphodiester bond
between the incoming nucleotide and the RNA transcript
what are the two types of terminator sequences - Correct answer--Rho-independent
terminator sequences they fold back on themselves to form a G-C hairpin loop and
release the mRNA transcript
©COPYRIGHT 2025, ALL RIGHTS RESERVE 2
,- Rho-dependent terminator sequences use specific rho factors which bind and use
ATP to move along the formed RNA transcript and destabilases the interaction
between RNA and DNA and releases of the complex
What are transcription factors? - Correct answer-mediate the binding of RNA
polymerase and the initiation of transcription
different types of RNA polymerase and their function - Correct answer--RNA
polymerase 1 and 3 both transcribe structural non coding RNA, 1 focuses on
Ribosomal RNA while 3 focuses on transfer RNA
-RNA polymerase 2 that transcribes the messenger RNA
identify and describe some post transcriptional modifications that occur at the end
of primary mRNA transcript - Correct answer--5' cap and 3' poly tail
-these modification are these to ensure the export of mRNA from the nucleus and
protect against ribonuclease enzymes which target phosphodiester bonds
Describe the 5' cap - Correct answer-7-methylguanosine is attached through a 5'-5'
triphosphate linkage
what are exons - Correct answer-sequences of mRNA that are needed for coding
the sequence of amino acids in the protien
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, what are introns - Correct answer-the intervening sequences that are transcribed
but not translated into protein
what happens if RNA splicing does not occur - Correct answer-the protein may not
have the correct sequences of amino acids
Describe RNA splicing - Correct answer-occurs at nucleotide sequences of introns
and is catalyzed by large molecules called spliceosomes made up of snRNP
-RNA spliceosomes can recognize and from base pairings with nucleotides at
designated splice sites which then allows for a OH group to attack and form a new
phosphodiester bond
What do nuclear pores do? - Correct answer-allow nuclear membrane to selectively
move molecules in and out of nucleus
What are frameshift mutations? - Correct answer-One or two base pair is added or
deleted, everything shifts, most of the amino acids will change.
what happens when three nucleotides are removed - Correct answer--no change in
the reading frame
-the identity of the protein is maintained
Proteins are synthesized from - Correct answer-ribosomes
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