Ch. 12 Bio
Select all of the following that are true about transcription.
- An mRNA copy of the DNA is produced. - It is the first stage of gene expression. - Information is transferred from DNA to RNA.
Select the correct statements about the process of translation.
- At translation initiation, mRNA binds to the small subunit of a ribosome, and then the large subunit binds to form a complete ribosome. - The ribosome moves down the mRNA three nucleotides at a time. - The sequence of the mRNA determines what tRNAs will bind, and what amino acids will be added to the polypeptide. - The tRNA bound at the P site moves to the E site as the ribosome moves to the next codon.
Select all of the following that describe genes in eukaryotes.
- contain sections called exons that encode polypeptides - have interrupting segments called introns
Select all of the following that are true about transfer RNA (tRNA).
- has an amino acid attachment site at its 3' end - has a folded, three-loop structure - contains an anticodon on one of its loops
Select all of the following that are steps leading to the production of a protein in eukaryotes.
- tRNA carries amino acids to the ribosome. - The primary mRNA transcript is processed to form mRNA. - DNA is transcribed into mRNA.
How many subunits make up a ribosome?
2
Transfer RNA (tRNA) carrying an amino acid binds to a ribosome at the ______.
A site
Choose the order that correctly describes the transfer of information in living organisms according to the central dogma.
DNA to RNA to protein
According to the central dogma, the genes contained in ______ are copied into RNA, which is used to direct the assembly of a sequence of amino acids in a ______.
DNA; protein
What statement describes gene regulation in multicellular organisms?
Genes are transcribed at the right time during development in a prescribed order.
Select the correct statement about genes in prokaryotic and eukaryotic cells.
In prokaryotic cells, genes occur as unbroken sections of DNA, while in eukaryotic cells, genes have interrupting segments called introns.
In gene silencing, what type of molecule may act after transcription to affect whether a particular mRNA is translated?
RNA
The silencing of genes that are complementary to double-stranded RNA is called ______.
RNA interference
Controlling whether ______ is able to bind to the ______ will affect the initiation of gene transcription in prokaryotes.
RNA polymerase; promoter
True or false: Not all genes are expressed at the same time.
True
In translation, a codon is ______.
a group of three nucleotides that determine the amino acid to be added to a polypeptide
An activator in prokaryotic cell transcription is
a regulatory protein that binds to the DNA and makes the promoter more accessible to RNA polymerase.
Over 50 different proteins and rRNA make up ______.
a ribosome
In a prokaryotic cell, an operon is ______.
a section of DNA containing a cluster of genes that are transcribed together
What is a gene?
a section of DNA that encodes a particular protein
A regulatory protein that binds to the DNA and makes the promoter more accessible so that RNA polymerase can bind and initiate transcription is called a(n) ______.
activator
microRNAs regulate gene expression ______.
after transcription
In translation, a sequence of nucleotides is translated into a sequence of ______.
amino acids
The ___ is a three-nucleotide sequence on a tRNA molecule that is complementary to an mRNA codon.
anticodon
During protein synthesis, transfer RNA ______.
brings amino acids to the ribosome
The triplet of nucleotides in mRNA that determines the amino acid to be added to a polypeptide sequence is called a(n) ______.
codon
The information specifying hereditary traits is encoded in blocks of DNA called ______.
genes
A primary transcript of mRNA ______.
includes both exons and introns
Sections of a eukaryotic gene that do not encode polypeptides and that are removed during RNA processing are called ______.
introns
What molecule brings the information from the DNA to the ribosomes for translation of the nucleotide sequence into the amino acid sequence of a polypeptide?
messenger RNA
What type of RNA conveys the information contained in a DNA sequence to the cytoplasm and directs the sequence of amino acids in a polypeptide?
messenger RNA
What type of RNA can regulate gene expression by preventing translation?
microRNA
The subunits of a ribosome ______.
nest together to form a functional unit
The regulation of gene expression ensures that ______.
not all genes are expressed at all times
A repressor stops transcription in prokaryotic cells by ______.
preventing the binding of RNA polymerase to the promoter
The unprocessed mRNA transcript is called a ______ transcript.
primary RNA
Gene expression in prokaryotes can be controlled by allowing access or blocking access of RNA polymerase to the ______.
promoter
The components of ribosomes are ______.
proteins and rRNA
The type of RNA that is a component of ribosomes is ______.
rRNA.
A region of ______ found in the small subunit of the ribosome corresponds to the leader region of all genes and causes the ______ to bind correctly to the ribosome during initiation of translation.
rRNA; mRNA
In eukaryotes, transcription factors are proteins that ______.
recruit RNA polymerase
Gene control in a multicellular organism functions to ______.
regulate the body as a whole
In prokaryotes, the molecule that binds to the promoter region of DNA and blocks the RNA polymerase from initiating transcription is called a(n) ______.
repressor
The site of protein synthesis is the ______.
ribosome
Exons are ______.
sections of eukaryotic genes that encode polypeptides
A ribosome functions in the ______.
synthesis of proteins
Transcription refers to the process of ______.
synthesizing RNA from a DNA template
The three sites on the ribosome that form dents or pockets are the sites where _____ binds.
tRNA
Translation is the term used to describe ______.
the production of a protein using mRNA
Given the following steps of translation, the formation of a peptide bond between an existing polypeptide and an amino acid forms right before ______.
the tRNA in the P site moves to the E site
At what stage do prokaryotes control most of gene expression?
transcription
In a process called ___ , an mRNA copy is made of DNA.
transcription
In gene expression, the production of RNA from DNA is called ______.
transcription
The mRNA product of ______ is used by ribosomes to produce a polypeptide in ______.
transcription; translation
In a process called ______, the order of nucleotides in mRNA is converted into an order of amino acids in a polypeptide.
translation
A section of DNA in a prokaryotic cell that contains a cluster of genes that are transcribed together is called a(n) ______.
operon
What type of RNA brings amino acids to the ribosome during translation?
tRNA
What process results in the production of messenger RNA?
transcription
In eukaryotes, transcription is more complex and requires not only RNA polymerase but also ______ that interact with RNA polymerase.
transcription factors
In gene expression, the production of a protein from RNA is called ______.
translation
Prokaryotes control gene expression mainly by ______.
turning transcription of genes on or off
Select all of the following that are true about an anticodon.
- complementary to a codon - determines which amino acid will attach to a tRNA molecule