chapter 7 smartbook

Vaccines work by causing

the immune system to recognize molecular components of the virus without the person having the disease

A latent viral infection is one in which

the viral genetic information remains inside the cell but does not cause disease symptoms

What three-base site of a tRNA molecule is complementary to an mRNA codon?

anticodon

During the elongation stage of translation, a _______ bond is formed between the incoming _______ acid and the growing polypeptide chain, and empty tRNAs are released from the ribosome

covalent; amino

All viruses contain genetic material, which is either RNA or ______, and a(n) ______ coat that surrounds the genetic material

DNA; protein

________ provides the raw material for evolution because it can create new alleles, which are alternative forms of the same ______

Mutation; gene

Select all of the reasons that gene regulation is advantageous in multicellular eukaryotic organisms.

Not all cells need all proteins encoded in the genome. It saves energy.

During transcription, what reads the template strand within a gene and adds complementary bases?

RNA polymerase

True or false: Gene regulation allows cells to produce only the proteins that they need.

True

true statement about viral infection of a host cell.

Viral penetration into a host cell may not cause immediate death of the host cell

The instructions in ______ encode the information that a cell needs to produce proteins, which are vital to living things.

dna

Transcription, translation, nucleotide synthesis, and modification of mRNA are all processes that require

energy

two characteristics that all viruses share

genetic material, either RNA or DNA a protein coat that surrounds the genetic material

In what type of bacteriophage infection does the host cell burst open, releasing the new viral particles?

lytic

How does a fever help fight a viral infection?

speeds immune responses

What role does DNA play in the cell?

store instructions for making proteins

The replacement of one DNA base with another is called a(n)

substitution mutation.

The first virus ever discovered was ______, a virus that infects over 120 plant species

tobacco mosaic virus

During (,) the information that is encoded in the DNA base sequence is copied into the complementary language of mRNA. Then, once the mRNA is produced and modified, a process called (,) uses that information to assemble a sequence of amino acids.

Blank 1: transcription Blank 2: translation

In the "central dogma" describing the flow of genetic information from DNA to protein, DNA is copied to RNA in a process called ( ) and the information in RNA is used to direct the synthesis of a protein in a process called ()

Blank 1: transcription Blank 2: translation

A variant of a gene is referred to as a(n)

allele

On a tRNA molecule, the () is a three-base sequence that is complementary to and binds to an mRNA codon during translation.

anticodon

After a virus attaches to and penetrates a host cell, a virus can enter a phase where symptoms of the infection are delayed or it can

cause immediate cell death

What symptom of influenza infection is due to dead and damaged host cells in the airway?

cough and sore throat

During the elongation stage of translation, a _______ bond is formed between the incoming _______ acid and the growing polypeptide chain, and empty tRNAs are released from the ribosome.

covalent; amino

After translation is complete, the newly synthesized protein must ______, as determined by some regions of the amino acid chain.

fold into its functional shape

An animal virus can cause a(n) ______ viral infection, in which disease symptoms are not produced immediately, but the viral information remains inside the cell

latent

a bacteriophage replicates and then causes the host cell to burst, thus killing it and releasing the new viral particles

lytic

In transcription, the genetic information in DNA is copied into a(n) ______ molecule, and in translation, the "message" in an mRNA molecule is translated into a(n) ______ sequence

mRNA; amino acid

is any external agent, such as X-rays or chemicals, that induces mutations

mutagen

UV rays, X-rays, some chemicals found in tobacco, and radioactive fallout are all examples of _____, agents that can damage DNA and cause mutations.

mutagens

A change in a gene sequence or a regulatory DNA sequence is called a(n) ______.

mutation

A(n) is a change in a cell's DNA sequence.

mutation

What describes a substitution mutation?

one DNA base is replaced with another

In bacteria, a(n) ______ is a group of genes under control of a single promoter.

operon

Tobacco mosaic virus (TMV) infects many species of

plants

RNA ______ is the enzyme that builds the RNA chain during transcription

polymerase

At the beginning of transcription, RNA polymerase binds to the ______ on the DNA.

promoter

The ______ is a sequence of DNA that signals the start of a gene and also which of the two strands of DNA is the template for transcription

promoter

The ______ is a sequence of DNA that signals the start of a gene and also which of the two strands of DNA is the template for transcription.

promoter

Select all of the following that are present in a bacterial operon.

promoter operator group of genes

Enzymes and chaperone proteins assist in ______ that takes place after translation is complete.

protein folding

In the "central dogma," information flows from DNA to RNA to ______.

proteins

Only producing proteins that are needed allows a cell to

save energy.

In eukaryotic cells, proteins called ______ factors bind at specific DNA sequences and form a pocket that allows RNA polymerase to initiate transcription

transcription

In eukaryotes, RNA polymerase cannot bind to the promoter and initiate transcription without the presence of regulatory proteins called

transcription factors.

Preventative treatments for viruses called ______ cause the immune system to recognize molecular components of a virus without exposing the person to the disease, conferring future immunity to the target virus

vaccines

Attachment, penetration, synthesis, assembly, and release are the stages of

viral replication

A small, infectious agent that is composed of genetic information inside of a protein coat is a called a

virus

a noncellular, small, infectious agent that is simply genetic information enclosed in a protein coat

virus or virion