genetics final

If tryptophan is amino acid #67 in a particular protein, what is the anticodon of the transfer RNA that delivered tryptophan to this location?

3'-ACC-5'

The polyadenylation signal sequence in eukaryotic mRNA is ______.

5' AAUAAA 3'

On the diagram, which letter represents the 5' and 3' untranslated regions as they appear in the processed transcript?

A

Initiation

A complex forms between the ribosomal subunits, one mRNA molecule and the first tRNA molecule.

What is a spliceosome?

A multicomponent structure that removes introns found in an RNA

What is a promoter?

A specific base-pair sequence that attracts RNA polymerase, either directly or indirectly

The complementarity rule used in transcription is similar to the ______ rule, except that ______ substitutes for thymine in the RNA.

AT/GC; uracil

Which of the following are possible posttranslational modifications?

Addition of a phosphate group Addition of ubiquitin Addition of a carbohydrate

Elongation

Amino acids are linked together in the order designated by the codons.

Which of the following represent common structural features of transfer RNA molecules?

Anticodon sequence Amino acid acceptor stem with a 3' single-stranded region 74-95 nucleotides in length Cloverleaf shape formed by complementary base pairing

Which of the following represent common structural features of transfer RNA molecules?

Anticodon sequence Cloverleaf shape formed by complementary base pairing Amino acid acceptor stem with a 3' single-stranded region 74-95 nucleotides in length

In prokaryotic cells, transcription and translation are coupled, i.e., translation of an mRNA begins _________its transcription has been completed.

BEFORE

Which of the statements correctly describe the energy requirements for transcriptional elongation?

Breaking a bond in a ribonucleotide triphosphate provides the energy needed to form a new bond between two nucleotides.

What are snRNPs?

Components of the spliceosome

The central dogma of genetics can be summed up by which of the following?

DNA → mRNA → polypeptide

Which of the following statements accurately describes the genetic code in different organisms?

In almost all organisms that have been examined by scientists, the same correspondence between codons and amino acids is found.

How does a hairpin loop form during termination of transcription in bacteria?

It forms within the mRNA through complementary pairing of nucleotides in the same molecule.

When a polypeptide is synthesized, the first amino acid to be put in place is located at the

N terminus

Addition of a phosphate group to a polypeptide is a

POSTTRANSLATIONAL MODIFICATION

Addition of a phosphate group to a polypeptide is a

POSTTRANSLATIONAL modification

Transcription is the process of synthesizing

RNA from a DNA template

A ribozyme is a(n) ____.

RNA molecule with catalytic activity

Which enzyme synthesizes RNA during transcription?

RNA polymerase

Which RNA polymerase transcribes genes that encode proteins in eukaryotes?

RNA polymerase II

Which components are assembled into the subunits of a ribosome?

Ribosomal proteins Ribosomal RNA

RNA splicing requires the aid of a multicomponent structure called the

SPLICESOME

Which of the following are functions of the 5' cap of eukaryotic mRNAs?

Stabilizes the mRNA in the cytoplasm Recognition of the transcript by translation initiation factors

Termination

The newly produced polypeptide is released from the ribosome.

A mutation in the E. coli tryptophan synthase gene produces glutamic acid (Glu) instead of glycine (Gly) at position 211 of the protein and the bacteria are unable to survive in the absence of tryptophan. A different mutation produces valine (Val) at the same position and the bacteria can survive in the absence of tryptophan. What is the conclusion from this result?

The tryptophan synthase enzyme can function with either Gly or Val at position 211.

Transcription occurs in how many stages?

Three stages: initiation, elongation, and termination

Which of the following nucleotides are used during transcription?

UTP and ATP CTP and GTP

A polyribosome is

a messenger RNA transcript that has many bound ribosomes in the act of translation

A polyribosome is ______.

a messenger RNA transcript that has many bound ribosomes in the act of translation

The capping of a eukaryotic mRNA is an event that involves the addition of

a methylated guanosine in reverse orientation.

The modification that occurs at the 3' end of eukaryotic mRNAs is known as _____.

a poly-A tail

The universality of the genetic code means that

all organisms have a common ancestor mouse mRNA can be translated by ribosomes from frog egg cytoplasm

When a polypeptide is synthesized, the first amino acid to be put in place is located at the ______.

amino- or N-terminus

Enzymes known as aminoacyl-tRNA synthetase , are responsible for attaching amino acids to their corresponding tRNAs.

aminoacyl synthetase

To bring a specific amino acid into its location on a polypeptide chain, which sequence on transfer RNA must bind to messenger RNA?

anti cordon

The order in which amino acids are added to a polypeptide chain is determined by hydrogen bonding between each codon and the ______ of the tRNA carrying the amino acid.

anticardon

During elongation, the ______ of the incoming tRNA binds to the ______ of the mRNA

anticodon; codon

During elongation, the ______ of the incoming tRNA binds to the ______ of the mRNA.

anticodon; codon

The 5' and 3' untranslated regions of a mature eukaryotic mRNA ____.

are located within exons facilitate efficient translation

The function of an aminoacyl-tRNA synthetase enzyme is to catalyze the

attachment of an amino acid to its appropriate tRNA

A loss-of-function mutation _____.

can occur outside the coding region can reduce the amount of functional protein can occur within the coding region

The addition of a methylated "backward G" to the 5' end of a eukaryotic mRNA is a process known as ______.

capping

The flow of genetic information in a cell, from DNA to RNA to protein, is described as the I genetics.

central dogma

The flow of genetic information in a cell, from DNA to RNA to protein, is described as the

central dogma of genetics

A series of three nucleotide bases that specifies a particular amino acid is a

codon

Which of the following is not a feature of transfer RNA molecules?

codon

What do scientists mean when they say that a gene's DNA sequence is colinear with the amino acid sequence of the encoded polypeptide?

colinear

During DNA replication, DNA polymerase forms phosphodiester bonds between ______ triphosphates, whereas during transcription, RNA polymerase forms bonds between ______ triphosphates.

deoxyribonucleotide; ribonucleotide

About 250 adenine nucleotides, called a ____________, are enzymatically added to a eukaryotic mRNA after it is transcribed.

during the initiation phase of transcription

A eukaryotic promoter differs from a prokaryotic promoter because _____.

eukaryotic promoters are bound by histone proteins that must be released

Regions of DNA that are represented in a mature transcript are

exons

Sequences known as exons are _____.

expressed regions of DNA that are present in a mature mRNA

A mutation that increases the activity of a protein is a _____.

gain-of-function allele

Which amino acid will be carried by a tRNA with the following anticodon: 3'-GUG-5'?

histodine

In bacteria, the term open promoter complex refers to the small bubble-like structure that forms

initialization

The three stages of transcription are called

initiation, elongation, and termination

Sequences of DNA that are not represented in the mature mRNA are called ____.

introns

are intervening sequences of DNA that are not represented in mature mRNA.

introns

A mutation in the location indicated by the thick blue arrow in the diagram

may alter the amount of protein produced by the gene.

A base substitution in DNA that ultimately leads to a change in the encoded amino acid is called a(n)

missense

A snRNP consists of small uridylic acid-uridylic acid-rich , and proteins.

nuclear rna

A nucleotide triplet, called a codon, specifies

one amino acid

A nucleotide triplet, called a codon, specifies ______.

one amino acid

About 250 adenine nucleotides, called a _______ are enzymatically added to a eukaryotic mRNA after it

poly-A or poly a

A single mRNA that contains the coding information for several distinct polypeptides is

polycistronic

The enzyme that synthesizes RNA from a DNA template is called

polymerase RNA

In ______ cells, the initiator tRNA carries the amino acid N-formylmethionine.

prokaryotic

The complex of RNA polymerase holoenzyme bound to an unwound template strand of DNA during the initiation phase of transcription is called the

promoter open

The sequence in DNA that signals RNA polymerase where to begin transcription is called the

promoter or promoters

Each ribosomal subunit is assembled from ribosomal RNA and many different

protein

Noncoding genes include those for

rRNAs snRNAs tRNAs

A coding region on a single DNA strand can be read in three different ways, depending on the position of the first codon. Thus, the first codon determines the region's

reading frame

During termination of translation in bacteria, a stop codon is recognized by a(n)

release factor

The component that recognizes a stop codon during termination of translation in bacteria is ______.

release factor

In prokaryotes, the transcription terminator is a

sequence in the transcript that specifies the end of transcription

The process that removes introns from a primary transcript and joins together successive exons is called RNA

splicing

An AUG codon, which specifies the amino acid methionine and is often the first codon that begins a polypeptide sequence, is called the

start codon

In prokaryotic cells, a transfer RNA carrying N-formylmethionine recognizes the ______ and is the first tRNA to bind to the ribosomal subunits, so it is called the initiator tRNA.

start codon

The series of three nucleotide bases that specifies the placement of the amino acid methionine at the beginning of a polypeptide chain is the _____.

start codon

The sequence in DNA that signals the end of transcription is known as the

terminator

While working on deciphering the genetic code, Crick and Benner hypothesized that each gene has a single starting point which establishes

the reading frame

RNA splicing refers to

the removal of introns from RNA

The poly-A tail added to eukaryotic transcripts serves

to enhance the efficiency of translation

The poly-A tail added to eukaryotic transcripts serves _____.

to increase the stability of the mRNA in the cytoplasm to enhance the efficiency of translation

The synthesis of an RNA molecule from a DNA template is called

transcription

Which type of RNA is shown in the figure?

transfer rna

The synthesis of a polypeptide molecule from an mRNA template is called

translation

In prokaryotic cells, the coupling of transcription and translation refers to ______.

translation of an mRNA beginning before its transcription has been completed.

The structure shown in the figure is a hairpin loop that forms _______.

within an mRNA during transcription termination as a result of complementary bases within an mRNA when RNA polymerase is being released from DNA