question

DNA is a double stranded helical structure.
?It is composed of nucleotides.
?Each nucleotide is a

answer

phosphate, a sugar (deoxyribose), and a nucleotide base.

question

The components of DNA bind together in a very specific way.
?This permits a ____ and ______ orientation of the nucleotide

answer

correct and precise

question

Nucleotides join to each other to form a chain.
?The ___________ of a sugar joins to the __________ of another nucleotide.
?This makes the linkage inherently polarized
?And gives structural orientation to the growing chain.

answer

3' hydroxyl group
5' hydroxyl group

question

adenine and guanine
are large double-ring structures

answer

DNA has two types of base
?Purines

question

thymine and cytosine
have smaller single ring structures.

answer

DNA has two types of base
Pyrimidines –

question

DNA STRUCTURE:
the strands are ____
one strand is orientented upsidedown relative to the other

answer

antiparallel

question

DNA is a chemically stable molecule.
Any mismatched pairing is

answer

chemically unstqable

question

is ususally found in single strand form
contains ribose

answer

RNA

question

helps maintain the proper shape of ribosomes.

answer

rRNA (ribosomal RNA

question

contains information derived from DNA (the messenge from the DNA that says this is what you make)

answer

mRNA (messenger RNA)

question

–carries amino acids to ribosomes

answer

?Transfer RNA

question

how DNA is copied
incrediably accurate and fast
critical cellular process

answer

DNA replication

question

occurs when the helix twists around itself
must be relaxed
is a characteristic of helical structures (because of this everything has to loosen up (unwound) b4 you can replicate).

answer

supercoiling

question

Strands must be uncoiled, unwound, and separated before replication.
?This is accomplished by two enzymes:

answer

topoisomerase and helicase

question

–unwinds the supercoils
unwinds the supercoils by breaking the DNa so the supercoil relaxes, and then resealing the break

answer

?Topoisomerase

question

–once the supercoiling has been relaxed this enzyme separates and unwinds the strands

answer

?Helicase

question

would produce two copies that each contained one of the original strands and one new strand.
cause you are conserving half

answer

semiconservative replication

question

There are two requirements for replication:

answer

An ample supply of each of the nucleotides adenine, thymine, cytosine, and guanine
A primer: template junction

question

( a sequence that tells replication to begins/ you have to have a starting point for replication)

answer

A primer: template junction

question

eacxh single strand of DNA is a

answer

template

question

a portion of DNA is paired w/ a short piece od RNA called a ________

answer

primer

question

DNA replication is

answer

unidirectional (preceeds in one direction)

question

gives the DNA polymerase (adds a lot of nucleotides to a strand of DNA) a place to add the next base
Binding is between the 3’end of one base and the 5’ end of the next base

answer

the primer:template junction

question

DNA REPLICATION:Direction
Elongation of the bases is from the 3’ end
This is required for

answer

chemical stability

question

?The binding of a new base uses energy released from

answer

pyrophosphate

question

DNA replication is performed this enzyme
forms new strands of DNA using the primer: template junction as a guide.

answer

DNA polymerase

question

aids in accurate replication
takes place @ the primer:template junction active site

answer

proofreading

question

with proofreading improperly paired bases are removed by an _____ (cuts out a nucleotide)

answer

exonuclease

question

the double helix is unwound and seperated here
DNA rep occurs here

answer

replication fork

question

The separated strands at the replication fork are anti-parallel and are identified as:

answer

leading strand and the lagging strand

question

The leading strand is in the correct orientation for bases added to the 3’ end of the primer: template junction.
?Replication moves towards the

answer

replication fork

question

is anti-parallel.
?It moves away from the replication fork.
?Bases are only added to the 3’ end of the primer: template junction
is replicated in pieces called Okazaki fragments

answer

the lagging strand

question

each _____ has its own short RNA primer.
It is created by an RNA polymerase called primase.

answer

okazaki fragment

question

When the fragment is finished, the enzyme _______ removes the primer.
The gap is filled in by DNA polymerase.
Fragments are linked together by DNA ligase-

answer

RNAase H

question

(its job is to join together fragments of DNA/ DNA glue/ glue DNA pieces together because of DNA and okaski fragments need to be attached)

answer

DNA ligase

question

INITIATION AND TERMINATION OF REPLICATION:
Initiation begins at a specific site on the chromosome: the _________

answer

orgin of replication

question

INITIATION AND TERMINATION OF REPLICATION:
Termination occurs when the entire chromosome has been

answer

copied

question

INITIATION AND TERMINATION OF REPLICATION:

?Replicated chromosomes are separated by ________

answer

topoisomerase.

question

always read in one direction
The message is translated in a fixed reading frame
There is no overlap or gap in the code

answer

codons

question

a segment of DNa that codes for a functional product

answer

gene

question

is the production of the functional product
two features:
it involves specific interactions between DNA and RNA
it is highly regulated

answer

gene expression

question

?It does not require a primer: template junction.
?RNA does not remain base-paired to DNA.
?It is not as accurate as DNA synthesis (because the RNA polymerase doesn’t have any proofreading).

answer

transcription

question

three steps to stranscription

answer

initiation elongation and termination

question

RNA polymerase unwinds strands of DNA and synthesizes the RNA:
It also re-anneals the strands( it puts the strands back together).

answer

elongation

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a sequence of DNA signals the end of transcription:
RNA polymerase detaches from DNA

answer

termination

question

a DNA sequence called the promoter initially binds the RNA polymerase:
This produces a bubble in the DNA.

answer

initiation

question

The sequence of nucleotides in messenger RNA is transformed into a sequence of amino acids.
It is directly affected by any errors in either DNA or RNA

answer

translation

question

It is a highly conserved (all cells do it) function seen in all cells.
It requires high levels of energy.
requires all three types of RNA –messenger, transfer, and ribosomal

answer

Translation

question

indicates the start of an amino acid sequence.
begins with a start codon.
Translation moves from the 5’end to the 3’ end.
ends with a stop codon

answer

An open reading frame (ORF)

question

mRNA in translation:
mRNA contains a segment that recruits the ribosomal subunits.
Ribosome and mRNA bind here through _______

answer

complementary base pairing

question

tRNA in translation:
Each tRNA attaches to a specific amino acid at the __________

answer

acceptor arm

question

It brings amino acids to the ribosome.
It binds to the ribosome at the anti-codon region using complementary base pairing

answer

acceptor arm

question

The ribosome is a honeycombed structure with tunnels. ?The components of protein synthesis enter these tunnels and move through them. ___ ________ ___________

answer

?mRNA ?tRNA ?Growing polypeptide chain

question

3 stages of translation

answer

initiation elongation and termination

question

requires:
Recruitment of the ribosome to the mRNA
placement of a methionine tRNA complex at the P site
Precise positioning of the ribosome over the start codon of mRNA.

answer

initiation in translation

question

, three things must occur in order for amino acids to be added to methionine.
A tRNA carrying the next amino acid is loaded into the A site.
A peptide bond forms between the amino acids.
Each tRNA moves (out one moves in)–the one at the A site to the P site, the one at the P site to the E site.

answer

elongation:
after initiation

question

in elongation the ________ moves along the mRNA

answer

ribosome

question

Translation continues until a stop codon enters the A site.
?Stop codons are recognized by specialized proteins.
?These specialized proteins cause the translation complex to fall apart.

answer

termination

question

during termination the peptide achain is released from the ribosome and begins to form ___________ and __________ structures

answer

seconday and tertiary

question

is energetically expensive and highly regulatied:
constituative genes
repressible genes
inducible genes

answer

regulation of gene expression:
protein synthesis

question

Some genes are on and can be turned off – (can turn off when need to).

answer

repressible genes

question

Some genes are always turned on – (always on).

answer

constitutive genes

question

Some genes are off and can be turned on –(can be turned on when needed)

answer

inducible genes

question

Gene expression is controlled by regulatory proteins:
_______. _____,

answer

activators, repressor

question

Gene expression is controlled by regulatory proteins:
_______. _____,

answer

activators, repressor

question

nvolved in positive regulation
DNa binding protein

answer

activators

question

invovlved in negative regulation
are DNA binding protein

answer

repressors

question

Regulatory proteins recognize two sites on DNA near the genes they control.

answer

the promoter and the operator

question

where the RNA polymerase binds. is adjacent to the operator

answer

the promotor

question

where regulatory proteins bind. adjacent to the promoter

answer

the operator

question

turns on genes that are off (repressed).
?The best example is the lac operon:

answer

induction

question

an _____ is a set of genes that is regulated.
?There are many in the chromosome

answer

operon

question

The lac system has two regulatory proteins
Both proteins bind at the operator site on DNA

answer

the lac repressor and the lac activator- CAP (caraboilte activator protein)

question

is always produced.
?It binds at the operator site and overlaps part of the promoter site

answer

the lac repressor

question

The lac repressor binds @ the operator site and overlaps part of the promoter site:
this blocks the RNA polymerase from _______
this prevents transcription of the _______

answer

attaching
lac gene

question

also binds at the operator site
?It recruits RNA polymerase to the site.
?It then interacts with the polymerase so it binds properly

answer

cap

question

For the genes of the lac operon to be turned on, the repressor must first be _____
occurs through an allosteric control mechanism

answer

inhibited

question

it then interacts w/ the polymerase so it binds properly

answer

expression of lac Operon:
allosteric control mechanism

question

The expression of lac genes is leaky
?A few transcripts are made and there is always a low level of ______
?This allows small amounts of __________ into the cell.

answer

?-galactosidase
lactose

question

the expression of the lac gene is leaky:
Lactose is converted to ______.
?_______ binds the lac repressor.

answer

allolactose

question

The expression of lac genes is leaky
?A few transcripts are made and there is always a low level of ?-galactosidase.
?This allows small amounts of lactose into the cell.
?Lactose is converted to allolactose.
?Allolactose binds the lac repressor.
?This changes the shape of the lac repressor and it _________________________________

answer

can no longer bind to the operator site

question

acts in a similar fashion to allolactose.
?Its activity is based on levels of cyclic AMP (cAMP).

answer

CAP

question

When cAMP levels rise, cAMP binds to ____

answer

CAP

question

cAMP binding to CAP:
causes a change to the _______ shape of cap
the cap-cAMP complex binds to the promoter site of the ________
this helps the RNA polymerase to bind to the _______
the lac genes are expressed

answer

3 dimensional
lac operon
promoter site

question

When cAMP levels fall, ___________
?RNA polymerase does not bind to the promoter site.
?The lac genes are not expressed

answer

no complex is formed.

question

There are also cellular mechanisms that turn off genes.
?This is very important for the conservation of energy.
has similar mechanisms to feedback inhibition

answer

repression

question

ex of repression ______ synthesis:

repressor is always produced but cannot bind DNA in its normal form.
?Excess binds the repressor and changes its shape so it can bind DNA and prevent gene expression.
?is a co-repressor of its own synthesis

answer

tryptophan

question

are changes in the DNA sequence.
?Change in DNA sequence can cause changes in proteins.
so they must be kept to a minimum

answer

mutations

question

simplest mutation
one base switched for another

answer

point mutation

question

drastic mutation caused by the insertion or deletion of bases

–¿This is caused by large insertion or deletion of bases
•(things that are going to change the reading frame) change how you will read the message and change what it’ll become in the end

answer

frameshift mutations

question

rates are low
certain sections oof the chromosome have higher rate (hot spots)

answer

spontaneous mutations

question

can reverse the primary mutation
instead of making a faulty protein you dont make a protein @ all

answer

suppressor mutations

question

by:
?Hydrolysis
?Deamination
?Chemical mutagens
?Alkylation
?Oxidation
?Base analogs
?Radiation

answer

DNa can be dammaged

question

cause double-strand breaks in DNA.

answer

gamma radiation and ionizing radiation

question

causes DNA damage through the formation of thymine dimers.

(big gap skipping 2 nucleotides/ reading frame mutations)

answer

ultraviolet radiation

question

damage to DNA that prevents replication

answer

radiation

question

look like DNA bases but aren’t.
?They can be mistakenly used in replication.
?This inhibits further replication.

answer

base analogs

question

what are the 3 principle mechanisms of DNA repair

answer

nucelotide excision, base excision and photoreactivation

question

?Repair enzymes look for damaged bases.
?The damaged base is removed from the double helix.
?A DNA polymerase fills in the gap.
?A DNA ligase repairs the break in the strand

answer

base excision

question

•In all organisms, NER involves the following steps:
•Damage recognition
•Binding of a multi-protein complex at the damaged site
•Double incision of the damaged strand several nucleotides away from the damaged site, on both the 5' and 3' sides
•Removal of the damage-containing oligonucleotide from between the two nicks
•Filling in of the resulting gap by a DNA polymerase
•Ligation

answer

nucleotide excision repair

question

•repairs thymine dimers.
–¿It is accomplished by an enzyme called photolyase.
–¿Photolyase binds to the dimer in the dark.
–¿Photolyase is activated by light and breaks the thymine-thymine bond.

answer

Photoreactivation

question

bacteria shuffling genes occurs by: transposition, transformation, conjugation, and transduction

answer

genetic recombination

question

genetic recombination that takes place w/in the same cell

answer

transposition

question

genetic recombination that takes place between cells:
______ __________
_____

answer

transformation, conjugation and transduction

question

transposition is caused by _______.
?move from one place on the chromosome to another.
?They can move into or out of the chromosome.
?They use cleavage and rejoining mechanisms

answer

transposons

question

Transposition causes random ___________.
?The results can be beneficial or detrimental.
?Beneficial changes will be selected for and maintained.
?They may be the reason for several human diseases.

answer

rearrangments

question

involves the shift of genetic material between cells. ?It involves naked DNA.

answer

transformation

question

is taken up by a bacterial cell and recombines with genes of that cell

answer

naked DNA

question

in transformation the ________ must be competent Must be able to take up large molecules such as pieces of DNA. ?Some bacteria are naturally competent, whereas others can become competent after chemical treatment. ?Only a small amount of DNA is actually taken up

answer

recipient cell

question

involves the transfer of genetic material between cells.
?It is a common event in both Gram-positive and Gram-negative bacteria.
?It uses a bacterial virus (phage) for transfer

answer

transduction

question

There are two forms of transduction:

answer

generalized- random
specialized- specific

question

?The original infected cell chromosome is cleaved into pieces.
?Some of this bacterial DNA is incorporated into a newly made phage.
?When these phages infect the next cell, original DNA recombines with host chromosome

answer

There are three phases to generalized transduction.

question

?Phage DNA incorporates into the host chromosome.
?Phage DNA excises itself from the host chromosome.
Part of the host DNA is taken along.
?Original host DNA is incorporated into the next host chromosome.

answer

During specialized transduction:

question

?Specialized transduction is used in

answer

biotechnology.

question

involves the transfer of material between cells.
?requires direct contact between the donor and recipient cells.
?DNA moves from the donor to recipient cell

answer

conjugation

question

conjugation requires direct contact between the donor and reciepient cells
______ stick together
______ use pili as a conduit for DNA transfer

answer

gram positive cells
gram negative cells

question

?The sex pilus of the donor cell recognizes specific receptors on the cell wall of recipient cell.
?An enzyme in the donor cell causes the plasmid DNA to unwind.
?One of the two single strands of plasmid DNA stays in the donor cell.

answer

There are several steps in conjugation:

question

The other moves across the plasmid into the recipient cell.
Both single strands are replicated.
After replication, the donor and the recipient contain identical plasmids

answer

There are several steps in conjugation:

question

can have several outcomes for the recipient cell:
?The plasmid can remain as a plasmid.
?The plasmid can become incorporated into the recipient cell chromosome.
?When this happens, the recipient cell is then referred to as Hfr.

answer

conjugation

question

Conjugation:
___________ from Hfrcan be moved into a new recipient.
?This replaces sections of the host chromosome

answer

DNA

question

mechanisms are involved in making pathogens more dangerous.

answer

?Many genetic

question

is closely associated with pathogenicity and virulence. ?It transfers virulence genes into bacteria that were previously harmless.

answer

genetic transfer

question

Genes for antibiotic resistance and toxins are found on

answer

plasmids

question

?Genes for resistance to disinfectants and environmental pressure are found on

answer

dissimilation plasmids

question

are defined as obligate intracellular parasites -they cannot live outside a cellular host. have only one goal –a productive infection are specific for a certain cell type

answer

viruses

question

Viruses can infect:

answer

?Bacteria (called bacteriophages)
?Plant cells
?Animal cells (human cells included in this group).

question

An intact viral particle

answer

virion

question

is surrounded by a protein coat called a capsid.

answer

viral nucleic acid

question

each is made up of capsomeres

answer

capsid

question

there are 2 types of viuses

answer

DNA and RNA viruses

question

structure must overcome two basic problems:

It must be strong enough to protect the viral nucleic acid. ?It must be able to release the viral nucleic acid for infection

answer

Virion

question

have specific nomenclature

answer

viruses

question

•It is built from identical protein units called capsomeres.
–¿Capsomeres bond together and give the _______ structural symmetry.
–¿Viruses possess either helical or icosahedral symmetry

answer

capsid

question

viruses possesss either ____ or _____ symmetry

answer

helical or icosahedral

question

There are two shapes of helical viruses:

answer

?Rod –straight and relatively rigid
?Filamentous –flexible, curved, or coiled.

question

Their shape is derived from 20 triangular faces that make up the capsid
2 types:
simple and complex

answer

ICOSAHEDRAL VIRUSES

question

Many viruses that infect humans and other animals have this
form when viral glycoproteins and oligosaccharides associate with the plasma membrane of the host cell.
all have a phospholipid bilayer

answer

viral envelopes

question

Envelopes vary in:

answer

?Size
?Morphology
?Complexity
?Composition

question

envelope glycoproteins are firmly embedded in the envelope bilayer
this is facilitated by domains of host membrane proteins called

answer

spanners

question

envelope glycoproteins can form spikes or other structures on the outside of the virion which can be used to attach to the

answer

host cell

question

important in infection
packaged either:
directly in the capsid
enclosed in special proteins
or enclosed in proteins from the host cell

answer

genomic packaging

question

the host cells fills with virions and bursts.
?The result is cell death.

answer

in a lytic infection

question

are also known as latent infections.
?The viral genome becomes incorporated into the host cell’s DNA.
?It can remain this way for an extended period.
?The host cell lives

answer

lysogenic infections

question

For animal viruses, there are six steps in lyticinfection:

answer

?Attachment
?Penetration
?Uncoating
?Biosynthesis
?Maturation
?Release

question

occurs when a virion binds to specific receptors on a host cell

answer

virion attachment

question

in virion attachment some viruses require a _______ to attach.
without it theres no infection

answer

coreceptor

question

interactions occur through random collisions.
?The number of viruses is extremely important.

answer

viral-host cell

question

WHEN VIRUS MEETS HOST CELL:

produce the maximum number of virions

answer

lytic infections

question

must be permissive for the infection to succeed.
?It must contain all of the components required to make new virions.

answer

the host cell

question

at the apical cell surface usually cause acute infection.
at the basolateral cell surface can become systemic

answer

viral infection

question

Many viruses attach only to specific areas of the host cell membrane _______.
?________ are rich in cholesterol, fatty acids, and other lipids.
?They are more reliable for stable attachment.
?They are also the site of release for many viruses.

answer

lipid rafts

question

Many different host cell molecules can be used as _____:
?Some viruses use more than one type.
?Some are shared by many viruses.
?can determine host range of virus

answer

viral receptors

question

is high affinity.
?There are conformational interactions.

answer

virus-receptor binding

question

Binding takes place between viral capsid and receptor.

answer

non-enveloped viruses

question

Binding takes place between viral envelope proteins and receptor

answer

enveloped viruses

question

Once attached, the virus must gain entry to the host cell.
?It must also ______ or _______ the capsid.

answer

uncoat or remove

question

?Uncoating can occur in three places:

answer

the plasma membrane
in the cytoplasm
@ the nuclear membrane

question

Use receptor mediated endocytosisto gain entry into the host cell

answer

PENETRATION & UNCOATING:Non-enveloped Viruses

question

?Virus is enclosed in a vesicle –the early endosome ?Early endosomesfuse with or become late endosomes. ?Late endosomesfuse with the lysosomewhere uncoatingbegins.

answer

receptor mediated endocytosis:
non enveloped viruses

question

some viruses pore in the host membrane

answer

PENETRATION & UNCOATING:Non-enveloped Viruses

question

fuses with the host cell membrane
?Fusion is mediated by specialized fusion proteins of the host cell.
?It results in the formation of a fusion pore –a large opening allowing viral entry.
?For some viruses, fusion requires the presence of co-receptor molecules

answer

PENETRATION & UNCOATING:Enveloped Viruses

question

Viral infection requires ____________ ?Viral genomes, capsids, and other viral proteins are synthesized in specific locations in the host cell.
Newly synthesized viral components are moved to other locations for assembly of viral particles

answer

compartmentalization

question

Viral infection requires compartmentalization.
Newly synthesized viral components are moved to other locations for assembly of __________

answer

viral compartments

question

Viral components are moved in vesicles, using host cell ________.
?Specialized host cell proteins are sometimes used.

answer

microtubules

question

DNA viruses use routine host cell _____ to cross the nuclear membrane.
?The pathways form pores in the nuclear membrane

answer

import pathways

question

RNA viruses use ____________ to convert RNA to DNA.
?Newly converted viral DNA is put into a pre-integration complex.
?This moves into the host cell nucleus during mitosis when the nuclear membrane is broken down

answer

reverse scriptase

question

are either DNA or RNA.
?Both can be single or double-stranded.

answer

viral genomes

question

use the same mechanisms as the host cell for biosynthesis. ?One strand of viral DNA is transcribed into mRNA. ?It uses either the host cell or viral RNA polymerase

answer

Double-stranded DNA Viruses

question

is used as a template to make a complementary copy of DNA.

answer

viral strand

question

Viral strand is used as a template to make a complementary copy of DNA.
?This uses the host cell’s ______.
?The ________ is transcribed into mRNA.
?It is also used to make new copies of the __________

answer

DNA polymerase
complementary copy
viral genome

question

requires:
?The synthesis of at least one viral protein
?The expression of several viral genes.

answer

BIOSYNTHESIS:Replication of DNA Virus Genomes

question

has the same configuration as host DNA.

answer

The viral genome

question

is performed by the host cell machinery

answer

replication of Dna virus genomes

question

viruses require much less DNA replication.

answer

latent DNA

question

synthesis is inhibited by the virus. ?All polymerases and proteins concentrate on viral DNA synthesis.

answer

host DNA

question

form in the host cell –replication compartments ?
They contain both DNA templates and host cell replication machinery.
?They are essentially viral factories.

answer

Specialized sites

question

allows exponential viral replication

answer

Compartmentalization

question

do not kill host cells. ?The viral genome is inserted into a host chromosome. ?Maximum replication is not required. ?A small number of viral genes are expressed. ?A limited number of viral genomes are replicated

answer

BIOSYNTHESIS:Replication of Latent DNA Viruses

question

Newly made viral DNA molecule is used as the template for
is performed by the host cell’s RNA polymerase.

answer

transcription

question

expression begins after DNA synthesis. ?Genes are expressed in a specific order.

answer

transcription: viral gene

question

Transcription with single-stranded DNA viruses is more complicated. ?The single DNA strands must first be converted to

answer

double strands

question

?Viral genes are transcribed at very high rates. ?This maximizes the number of

answer

new viruses being produced

question

Rapid ______ of viral DNA is regulated by host cell proteins. ?______ is coordinated with viral DNA synthesis. ?All host cell _______ and protein synthesis is shut down by the virus.

answer

transcrition

question

Mechanisms of biosynthesis are more complicated than in DNA viruses. ?Host cells do not possess RNA-dependent polymerases.

answer

RNA Viruses

question

They are required to make viral mRNA and replicate genomes. ?Viruses must carry one

answer

RNA-dependent polymerases.

question

are RNA viruses that contain the enzyme reverse transcriptase. cause latent infections.

answer

retroviruses

question

converts RNA into DNA. ?Converted viral DNA can be inserted into the host cell _________

answer

reverse transcriptase

chromosome

question

Involves the movement of newly made viral components to specific sites in the host cell.

answer

maturation

question

?There are two steps in maturation:

answer

?Intracellular trafficking ?Assembly

question

Some viral components are synthesized in the cytoplasm, and some in the nucleus. ?They are transported through the cell by host cell microtubules to assembly sites.

answer

Intracellular Trafficking

question

depend on: ?The type of genome (DNA or RNA) ?The mechanism of genome replication ?The presence or absence of an envelope

answer

?Assembly sites

question

in intracellular trafficking many _______ viruses assemble near the host cell membrane ?Others assemble near membrane bound organelles.

answer

enveloped

question

in intracellular tafficking these viruses assemble in the host cell nucleus

answer

Non-enveloped

question

in intracellular traffiking travel from the assembly site to the cell membrane in vesicles.

answer

viral proteins

question

in intracellular trafficking _____ transport depends in whether the virus has an envelope

answer

viral genome transport

question

in intracellular traficking ___________ genomes move to sites near the membrane

answer

enveloped viruses

question

in intracellular trafficking ________-genomes move to the host cell nucleus.

answer

?Non-enveloped viruses

question

All virions must complete a common set of assembly reactions. ?Formation of structural subunits for the capsid ?Assembly of the capsid ?Association of viral genome within the capsid ?Assembly of viral envelope glycoproteins.

answer

Enveloped viruses:

question

All virions must complete a common set of assembly reactions: ?Formation of structural subunits for the capsid ?Assembly of the capsid ?Association of the viral genome within the capsid.

answer

non enveloped viruses

question

Capsomeres are assembled 1st. ?Assembly is diff in DNA viruses & RNA viruses. ?The # of capsomeres produced is always more than the # required. ?This maximizes the chances of capsomeres finding each other.

answer

ASSEMBLY: Capsids

question

can be assisted by host chaperone proteins.

answer

capsid assembly

question

ASSEMBLY: Viral Genomes This is the most important part of assembly. ?There are two mechanisms:

answer

Concerted assembly and sequential assembly

question

–the viral genome is inserted into already assembled capsid

answer

?Sequential assembly

question

–the virion is assembled while the viral genome is being synthesized

answer

?Concerted assembly

question

New virions can be released from the host cell in two ways:

answer

?Lysis ?Budding

question

Non-enveloped viruses use _ forr release. ?This causes death of the host cell.

answer

lysis

question

?Enveloped viruses use _____ for release. ?This allows the host cell to live for a while.

(picking up that piece of envelope on the way out of the cell).

answer

budding

question

release: ?In some viral infections, ________ are non-infectious. ?Viral enzymes convert them into an infectious form after release.

answer

completed virions

question

can spread from cell to cell. ?They can use tight junctions between cells. ?They can also spread through the formation of syncytia.

answer

viruses

question

allow movement through the body without exposure to the immune system

large globs of viruses/ can move through the blood stream to make it to one part of the body to the other

answer

formation of synctica

question

spread: Some viruses produce _____: ?These are empty capsids or non-infectious virions ?They confuse and distract the host defenses.

answer

decoy virons

question

spread: Some viruses incorporate host proteins as a type of

answer

camouflage

question

can be:

Acute (rapid and self limiting)
?Persistent (long term)
?Latent (extreme versions of persistent infections)
?Slow or transforming (complicated types of persistent infections)

answer

Viral infections

question

produce virions and kill host cells rapidly (cytopathology

answer

Cytopathic viruses

question

viruses produce virions but do not cause cytopathology

answer

?Noncytopathic

question

me viruses dont produce virions or cause cytopathology but

answer

still cause infection

question

periods vary for different viruses.
?Some are as short as days.
?Some are as long as years.

answer

incubation periods

question

during the incubation period the virus is ______
the host is beginning to ______

answer

replicating
respond

question

varicella zoster is

answer

chicken pox

question

rapid production of virions & elimination of infection;
virions can be missed and spread to other tissues
this then causes reinfection
ex: varicella-zoster

answer

acute infections

question

severe public health problem
associated w/ epidemics
short incubation period
which causes a delay in indentifiable symptoms until the virus has already spread

answer

acute infections

question

Acute infection epidemics are often seen in

answer

crowded populations.
?Schools
?Military bases
?Nursing homes

question

hosts that survive acute infections are immune to __________ for life:
some diseases escape this immunity

answer

reinfection

question

(changes in virion structure)
reinfection occurs because of this
it is due to the specificity of the immune reponse
the new structure isnt recog by the immune system memory

answer

antigenic variation

question

there are 2 forms of antigenic variation

answer

antigenic drift and antigenic shift

question

Involves major changes in virion structure
?Is due to the acquisition of new genes
?This is through co-infection or recombination

answer

?Antigenic shift

question

Involves small changes in virion structure
?Results from mutations
?Occurs after the infection has begun

answer

antigenic drift

question

Caused when host defenses are either modulated or completely bypassed.
?Virions are produced for months or even years.

answer

PERSISTENT INFECTIONS

question

There are two variations of persistent infections

answer

chronic and latent infection

question

the infection lasts for life

answer

latent infection

question

the infection is eventually cleared

answer

chronic infection

question

host defense mech against viral infec
They must be given the signal to begin killing infected cells.
Some viruses can kill them first.

answer

cytotoxic T cells

question

some viruses escape killing by infecting tissues that have reduced immunosurveillance

answer

skin
central nervous system

question

?No large-scale production of virions
?Reduced or absent immune response
?Persistence of an intact viral genome so infections can reoccur

answer

latent infections

question

can be reactivated years after entry into host.

answer

latent viruses

question

are lethal.
?They are usually associated with brain infections.
?Signs may not be seen until years after the primary infection.
?Once signs and symptoms appear, death usually follows very quickly

answer

slow infections

question

?Sufficient number of viruses present ?Access to susceptible and permissive host cells ?An ineffective host immune response

answer

There are three basic requirements for successful infection

question

are disseminated within the host and transmitted from one host to another.

answer

viral infections

question

refers to spread of virus within an infected body.
?There are common sites for viruses to enter into the body.

answer

viral disssemination

question

what are the three main entry points for viral dissemination

answer

respiratory system, digestive system and the urogenital tract

question

The most common portal of entry into the human body.
?It is always exposed to large numbers of potential pathogens.
?Viruses easily disseminate from here into other areas of the body

answer

respitory tract

question

is the second most common portal of entry.
?Many viruses use this portal of entry.
?They must be resistant and resilient to harsh environments in order to survive.

answer

the digetive tract

question

in the digestive tract some viruses use transcytosis through _______ to enter the body
some viruses stay in the _____ and eventually destroy them

answer

M cells

question

their destruction causes inflammation of the digestive tract and diarrhea

answer

M cells

question

The primary point for sexually transmitted viruses to enter the body.
?Some remain in this tract and cause local infections e.g. genital warts.
?Some gain access to underlying tissues and disseminate throughout the body.

answer

urogenital tract

question

viruses also use this
like when they enter through the eyes
ex: opthalmic herpes infection

answer

portals of entry

question

Some viruses enter through the skin.
?Usually by _______ transmission from biting insects
?If they remain in the epidermis, a localized, ______ infection occurs.
?If they get into the dermis, a ____ infection can occur

answer

vector
acute
systemic

question

They can disseminate throughout the entire body.
?Some target neurons.
?Some use neurons to get to their preferred target area.

answer

viral dissemination in the nerous system

question

Viruses released from the apical surface host cells cause

answer

localized limited infection

question

?Viruses released from the basement membrane of host cells can

answer

spread systemically

question

?The bloodstream is the best route for systemic viral infection.
?Referred to as

answer

hematogenous dissemination

question

refers to virus replicating in the blood

answer

viremia

question

refers to the spread of the virus from one host to another

answer

viral transmission

question

there are 2 patterns of viral transmission

human to human and animal to human?

answer

transmission w/ in a single species
transmission between species

question

Viruses can be transmitted in several ways:
?Via _____ or inanimate objects
?Via poor techniques employed by health care workers: ___________
?________ –the digestive tract

answer

fomites
iatrogenic transmission
Fecal-oral route

question

Viruses can be transmitted in several ways:
?Respiratory tract Viruria Urogenital tract ?
Contact with ?

answer

the sneeze is the best form of transmission
transmission via urine
sexual transmission
skin

question

infections are seasonal.
?Respiratory tract infections are higher in winter.
?Digestive tract infections are higher in summer.

answer

most acute viral

question

in pregnant women can expose the fetus to infection

answer

viremia

question

some virus transmission from mother to infant can occur through

answer

breast feeding

question

the capacity of an infectious organsim to cause disease

answer

virulence

question

viruses can cause significant damage

answer

virulent

question

(attenuated) viruses cause little or no disease.

answer

nonvirulent

question

–how much virus is required to paralyze 50% of a subject population.

answer

PD50 (way to measure viral virulence ID50 & LD50 as well)

question

can be directly affected by:
?Route of entry
?Age and health of host
?The gender of the host

answer

virulence

question

?Susceptible –can be infected and can also transmit the infection
?Immune –cannot be infected

answer

There are two types of host:

question

caqn gender play a role in infection?

answer

?Males are more susceptible to viral infection than females.

question

the most effective way to deal with viral infections.
?It allows for life-long immunity from a particular infection.
?It increases herd immunity

answer

vaccination

question

what are the 3 groups of vaccines

answer

live attenuated cavvine
inactivated or killed vaccine and subunit vaccine

question

made of intact virions rendered non-infectious

answer

live attenuated vaccine

question

composed of killed or dead virons

answer

inactivated or killed vaccine

question

cposed of immunogenic parts of virions

answer

subunit vaccine

question

antigen is administered and causes the onset of the immune response

answer

avtive immunization

question

a preformed antiviral product, such as antibody, is administered

answer

passive immunization

question

can inactivate genes responsible for suppressing tumor formation.

answer

retroviruses

question

Some viruses can cause _____ in animals.
?An estimated 20% of human ______ involve viruses

answer

cancer

question

Viruses associated with human cancers include:

answer

?Epstein-Barr virus
?Hepatitis B and C viruses
?HPV

question

for many products that modify or block host defense.
?A battle wages between the host immune system and these modifications

answer

viral genomes code

question

are usually opportunistic infections and have increased with the number of immunocompromised individuals

answer

fungal infections

question

Parasites can be divided into two groups:

answer

? Protozoans – microscopic, single-celled eukaryotes.
? Helminths – macroscopic, multicellular worms.

question

Disease causing parasites depend on their ______ for survival

answer

infected host

question

are intestinal parasites that infect 10% of the world population

answer

entamoeba

question

parasites infect 16 million people in Latin America each year

answer

trypanosoma

question

vary in size.
?They contain membrane-bound nuclei and cytoplasm.

answer

paracytic protozoans

question

the cytoplasm of parasitic protozoans are divided into

answer

inner form- endoplasm
and outer form-ectoplasm

question

parasitic protozoans can be classified on the basis of their methods of

answer

movement and reproduction

question

Are facultative anaerobes
?Are heterotrophs
?Have a highly developed reproductive system

answer

most infectious protozoans

question

some infectious protozoans form ____ as a way of protecting themselves. they can also be a mech of transmission from host to host

answer

cysts

question

are worms.
?There are two types:
?Free living
?Parasitic
?They are bilaterally symmetrical and of various lengths

answer

helminths

question

parasitic helminths body is covered by a tough cellular ______
some have suckers, hooks, or plates which are used for _______

answer

cuticle
attachment

question

?Differentiated organs
?Primitive nervous systems
?Primitive excretory systems
?Highly developed reproductive systems
?They do not have a circulatory system.

answer

All helminths have:

question

comes in 2 forms: gastrointestinal form and blood and tissue form

answer

nematodes (round worms)

question

use only one host to complete their life cycle

answer

gastrointestinal form of nematodes

question

uses multiple hosts to complete their life cycle

answer

blood and tissue form of nematode

question

what are the three types of helminth that can infect humans

answer

cestodes (tapeworms), trematodes (flukes), nematodes (round worms)

question

?Have a flat, ribbon-shaped body ?The head contains suckers and frequently has hooks for attachment. ?They generate proglottids– reproductive segments with male and female gonads. ?Have no digestive tract - nutrients are absorbed across their cuticle. ?Some use one host and others two for their life cycle.

answer

cestodes (tapeworms)

question

Have leaf-shaped bodies ?They have two suckers. ?Oral sucker –takes in nutrients and regurgitates waste ?Distal sucker –used for attachment

answer

trematodes (flukes)

question

Pathogenesis of protozoan diseases is variable. ?The severity of infection is related to the number of worms. ?A large worm load lead to increased disability of the host

answer

for helminths

question

can cause: ?Tissue damage ?Allergic or anaphylactic reactions

answer

The host defense reaction

question

are intracellular parasites. ?They alternate between sexual and asexual reproduction

answer

sporozonans

question

most important sporozoans diseases that together affect 1/3 of the world's population

answer

malaria and toxoplasmosis

question

febrile illness found worldwide transmission by bite of anopheles mosquito mortality mainly seen in children and immunocompromised adults

answer

malaria (plasmodium species)

question

Male fertilizes female gametocytes ?Resulting zygote forms an oocyst filled with sporozoites ?Oocyst ruptures releasing sporozoites into body ?Sporozoites penetrate salivary glands

answer

(plamodium) Sexual life cycle begins when a mosquito ingests infected blood

question

Sporozoites are introduced with mosquito saliva. ?Sporozoites move to the liver and produce merozoites. ?Hepatocytes rupture releasing the merozoites. ?Merozoites infect red blood cells (ring stage).

answer

Asexual life cycle begins when a mosquito bites new host.

question

Within 72 hours, infected red blood cells begin to rupture. ?Merozoites are released. ?Some infect other RBCs. ?Some transform into the gametocyte form. ?Gametocytes are then taken up by the next mosquito

answer

life cycle of the plasmodium

question

Fever ?Anemia ?Circulatory changes thrombocytopenia

answer

Symptoms of malaria include:

question

is caused by the destruction of red blood cells. ?It is accompanied by depression of marrow function and an enlarged spleen

answer

anemia in malaria

question

two factors involved in the treatment of malaria

answer

species of plasmodium and the immunocompetency of the infected individual

question

are amebas. ?The most primitive form of protozoans that: ?Multiply by simple binary fission ?Move by using pseudopodia. ?Produce a chitin wall for protection

answer

rhizopods

question

rhizopods produce a chitin wall for protection that is referred to as a

answer

cyst

question

is an obligate intracellular parasite. ?It is passed from host to host as cysts. ?Uses the fecal-oral route of infection ?Ingestion of a single cyst can cause infection

answer

AMEBIASIS (ENTAMOEBA HISTOLYTICA)

question

is the third highest parasitic cause of deaths worldwide. ?Only malaria and schistosomiasis are higher. ?is on the rise in the US

answer

amabiasis (entamoeba histolytica)

question

LIFE CYCLE OF ENTAMOEBA HISTOLYTICA: ?It is found in either the ________ form.

answer

trophozoiter cyst

question

Initial infection is via the fecal-oral route. ?Systemic ________ occurs only after the colon colonized

answer

PATHOGENESIS OF AMEBIASIS amebiasis

question

pathogenesis of amebiasis the parasite produces several virulence factors and enzymes which can cause membrane ____ and _______

answer

lesions and cellular death

question

w/ amebiasis the infection is usually mild and asymptomatic. lesions can open the intestine for _______ and __________

answer

bacterial and viral infection

question

in amebiasis cysts can pass through the stomach and into the small intestine here they disintegrate and release four

answer

trophozoites

question

are widespread in nature. ?They use flagella for movement through the host. ?They multiply by binary fission

answer

flagellates

question

what are the four flagellates that cause disease in humans

answer

?Trichomonas ?Giardia Leishmania ?Trypanosoma

question

these 2 flagettes are noninvasive, have low morbity rates and theres no intermediate host required

answer

Trichomonas ?Giardia

question

these 2 flagellates are invasive, have high morbidity rates, are frequently lethal and required an intermediate host
(associated w/ the sandfly)

answer

leishmania and tryanosoma

question

is a sexually transmitted infection.
It produces vaginitis in females with symptoms:
Pain ?Dysuria ?Discharge

answer

TRICHOMONIASIS (TRICHOMONAS VAGINALIS)

question

It may cause prostatitis or urethritis in males. ?It can last from weeks to months. ?An estimated 180 million people worldwide are infected each year. ?The peak age of infection is 16 to 35 years old.

answer

TRICHOMONIASIS(TRICHOMONAS VAGINALIS)

question

does not form cysts. ?It can survive outside the host for 1 to 2 hours. ?In water, semen, or urine, it can survive for up to 24 hours.

answer

trichomonas

question

Direct contact transmission to genital endothelial cells causes the infection. ?Cells are destroyed and inflammation occurs. ?It is accompanied by petechial hemorrhaging. is noninvasive

answer

pathogenesis of trichomoniasis

question

TRICHOMONIASIS: ?Infection causes persistent ______. ?Symptoms can last for months. ?Severe cases can cause ________ and ________.

answer

vaginitis
hemorrhaging and tissue errosion

question

It is caused by the protozoan _______
;
Motile ?Fusiform ?Moves in a spiral fashion
;
The vector is the tsetse fly (Glossina species).

answer

TRYPANOSOMIASIS
;
Trypanosoma.

question

there are 2 forms of trypanosomiasis the african form which causes ____ and the american form which causes _____

answer

sleeping sickness
;
chaga's disease

question

is caused by trypanosomissis and is confined to central Africa. ?There are ten to twenty thousand cases each year. ?The reservoir is humans

answer

sleeping sickness

question

PATHOGENESIS OF TRYPANOSOMIASIS:
Parasitemia causes localization of parasites in __________ the heart and CNS are particularily vulnerable

answer

SMALL BLOOD VESSELS

question

PATHOGENESIS OF TRYPANOSOMIASIS

answer

Symptoms include:
Hemorrhaging ?Demyelinating panencephalitis ?Headache ?Fever ?Lymph adenopathy ?Skin rash ?Impaired mental status

question

TRYPANOSOMIASIS
?Symptoms can progress to:

answer

?Eventual diminished alertness. ?Indistinct speech, tremors, and coma. ?Coma can lead to death.

question

what are the subgroups for nematodes

answer

intestinal nematodes and tissue nematodes

question

have the following characteristics: ?Fusiformbody shape ?Tough outer cuticle ?Male and female forms ?Thousands of offspring are produced ?Eggs must incubate outside the host to become infective ?There is a larval form

answer

Intestinal nematodes

question

what type of nematodes are these?
Pinworms
?Whipworms
Large roundworms

(eggs must incubate outside the host)

answer

intestinal nematodes

question

can produce:
?Malnutrition
?Discomfort
Anemia
Occasionally death

answer

intestinal nematode infection

question

severity of intestinal nemotodes in directly correlated to worm load.
small worm load ?
large worm load ?

answer

pinworm (enterobius vermicularis)

question

pathogenesis of enterobiasis:

pinworms attach to the mucosa of the _______
females migrate down the ___________ to lay eggs

answer

cecum

perianal

question

once pinworms lay eggs: eggs stick to tissue, bedding towels and fingers eggs can be inhaled or swallowed eggs hatch in the upper intestine larvaw migrate down to the ______

answer

cecum

question

?Tissue nematodes can induce disease in:

answer

tissue blood and lymph systems

question

Four major types of ________ use humans as definitive hosts. ?They can live for years in subcutaneous tissues and lymph vessels.

answer

tissue nematodes

question

?Tissue nematodes discharge live offspring called ________. ?Circulate through the blood or tissue ?Can be ingested by blood sucking insects

answer

microfilariae.

question

Caused by the parasite Trichinella spiralis:
Lives in the duodenum and jejunum of flesh eating mammals. ?Particularly found in swine and bears

answer

TRICHINOSIS

question

enters through the host vascular system and is distributed widely. ?Only parasites that penetrate the skeletal muscle survive. ?It can become encapsulated in muscle. ?It can remain viable for 5-10 years.

answer

trichinella

question

The disease is widespread amongst swine.
?Human infection results from eating undercooked meat. ?Over one million people in the US carry either living or dead worms. ?Most infections are asymptomatic

answer

TRICHINOSIS

question

lesions

answer

in trichinosis ________ are nfound in striated muscle ?Heart muscle ?CNS

question

PATHOGENESIS OF TRICHINOSIS

The area of infection is infiltrated by white blood cells, particularly ___________.
Worms mature in 24-48 hours of eating ______

answer

eosinophiles tainted meat

question

symptomes of trichinosis include

answer

nausea, andominal pain and diarrhea

question

PATHOGENESIS OF TRICHINOSIS:
?Larval invasion starts _______ later.
Lasts one to ______
Low worm load – __________
?Large worm load – ________

answer

one week
six weeks
asymptomatic
significant disease and poss death

question

are commonly called tapeworms. ?The largest of the intestinal parasites ?Lack a vascular and respiratory system ?Lack a gut or body cavity ?Nutrients are absorbed across the cuticle

answer

cestodes

question

pathogenesis of cestode infec:
in the _____:

the worms stays in the lumen of the gut
only minor symptoms are seen

answer

primary host

question

pathogenesis of cestode infection:
in the ____________:
larval stages of the worm cause serious tissue invasion most patients are asymptomatic

answer

intermediate host

question

PATHOGENESIS OF CESTODE INFECTION ?Symptoms include

answer

?Gastric disfunction ?Nausea ?Diarrhea ?Weight loss

question

are known as flukes. ?Have a bilateral symmetry ?Have two deep suckers: ?One in the oral cavity ?One on the ventral side of the worm

answer

trematodes

question

can live for decades in human tissue and blood vessels. ?They produce progressive damage to vital organs.

answer

trematodes

question

Eggs are excreted from the human host.
They must reach water in order to hatch.
Hatching releases larvae called miracidia.
Miracadia penetrate snails, the intermediate host

answer

TREMATODES life cycle

question

LIFE CYCLE OF TREMATODES: Miracadia develop into _______.
_______ are released from the snail.

answer

cercariae

question

DISEASE CAUSING TREMATODES

Three major groups of flukes invade humans:

answer

?Lung flukes –?Liver flukes –?Blood flukes –

question

?Infections are frequently caused by consuming infected shell fish ?Infections cause eosinophilia and inflammation. ?After infection a capsule forms around the fluke

answer

paragonimiasis: lung flukes

question

is the study of fungi

answer

mycology

question

are important for the environment
are commensal organisms.
?They are normally harmless to humans. can be opportunistic pathogens

answer

fungi

question

are eukaryotes. ?There are two forms: ?Molds –multicellular ?Yeasts –unicellular

answer

fungi

question

Fungi use __________ metabolism

They obtain carbon from decaying organic matter.

answer

heterotrophic

question

Most fungi are _______ aerobes but some are ___________ anaerobes. ?No fungi are _____

answer

obligate facultative obligate anaerobes.

question

?Fungi reproduce either sexually or asexually. ?Involves spores -ascospores, zygospores, or basidiospores

answer

sexual reproduction

question

?Fungi reproduce either sexually or asexually. ?Through conidia ?Involves mitotic division and budding

answer

asexual reproduction

question

•Some fungi can grow in mold or yeast form
•The_____ form requires environmental conditions similar to in vivo
•   proper temperature
•   increased nutrients
•The ________ form requires:
•   ambient temperatures
   minimal nutirents

answer

yeast

mold

question

form of fungi that requires environmental conditions similar to in vivo. ?Proper temperature ?Increased nutrients

answer

yeast

question

form of fungi requires: ?Ambient temperatures ?Minimal nutrients

answer

mold

question

fungi are classified by: ?Ribosomal RNA typing ?The tissue types they parasitize ?The diseases they produce

answer

medically important

question

are classified into 4 groups:

Superficial mycoses ?Mucocutaneous mycoses ?Subcutaneous mycoses ?Deep mycoses

answer

?Fungal diseases

question

Fungal infections that do not involve a tissue response: ?Piedra, Tinea nigra, Tinea capitis, favus, and pityriasis

answer

SUPERFICIAL MYCOSES

question

–colonization of the hair shaft causing black or white nodules

answer

?Piedra

question

brown or black superficial skin lesions

answer

Tinea nigra

question

folliculitis on the scalp and eyebrows

answer

?Tinea capitis

question

–destruction of the hair follicle.

answer

favus

question

–dermatitis characterized by redness of the skin and itching:
?Caused by hypersensitivity reactions to fungi normally found on skin
Mostly seen in immunocompromised patients

answer

pityriasis

question

Associated with: ?Skin ?Eyes ?Sinuses ?Oropharynx and external ears ?Vagina

answer

CUTANEOUS AND MUCOCUTANEOUS MYCOSES

question

(type of cutaneous and mucocutaneous mycoses)
skin lesions characterized by red margins, scales and itching: ?Restricted to the stratum corneum. ?Classified based on location of infection

answer

ringworm

question

ringworm on feet or between toes

answer

tineapedis

question

ringworms between the fingers, in wrinkles on the palms

answer

tineacorporis

question

ringworms lesions on the hairy skin around the genetalia

answer

tineacruses

question

ringworms in scalp and eyebrows

answer

tineacapitis

question

chronic infection of the nail bed ?Commonly seen in toes

answer

?Onychomycosis

question

type of cutaneous and mucocutaneous mycoses that has extended scaly areas on the hands and feet

answer

Hyperkeratosis

question

colonization of the mucous membranes ?Caused by the yeast Candida albicans ?Often associated with a loss of immunocompetence

answer

mucocutaneous candidiasis

question

?There are two clinical types of mucocutaneous candidiasis:

answer

thrush and vulvovaginitis

question

fungal growth in the oral cavity ?An indicator of immunodeficiency.

answer

thrush

question

fungal growth in the vaginal canal
?Can be associated with a hormonal imbalance

Or can be caused by a superinfection caused by the use of an antibiotics which wipes out normal microflora in the body

answer

vulvovaginitis

question

Can cause the development of cysts and granulomas. ?Provoke an innate immune response -eosinophilia

answer

localized primary infections of subcutaneous tissue

question

Usually seen in immunosuppressed patients with: ?AIDS ?Cancer ?Diabetes

answer

deep mycoses

question

?Can be acquired by: ?Inhalation of fungi or fungal spores ?Use of contaminated medical equipment

answer

deep mycoses

question

?Deep mycoses can cause a systemic infection - __________ ?Can spread to the skin

answer

disseminated mycoses

question

very uncommon in immunocompetent individuals are more common in immunodeficient patients

answer

fungal infections

question

fungi can become invasive. ?They switch from yeast form to mold form. ?The hyphae invade tissues and disseminate

answer

some dimorphic

question

?Fungi do not produce exotoxins in vivo. ?Primary ________ is due to host inflammatory response.

answer

tissue injury in fungal infections

question

?Host defense against fungal infection is primarily through:

answer

?Phagocytosis ?Adaptive immune response

question

cause antibiotic resistance

answer

mutations

question

classification of viruses

1.Type of genetic material
2.Shape of the capsid
3.Number of the capsomere
4.Size of the capsid
5.Presece/absence of an envelope
6.Type of host it infects
7.Type of disease it produce
8.Target cell
9.Immmunological and antigenic properties

answer

1.Type of genetic material
2.Shape of the capsid
3.Number of the capsomere
4.Size of the capsid
5.Presece/absence of an envelope
6.Type of host it infects
7.Type of disease it produce
8.Target cell
9.Immmunological and antigenic properties

question

protein molecule forming capsid

answer

capsomere

question

protein shell surrounding nucleic acid
protein coat

answer

capsid

question

nucleic acid plus capsid

answer

nucleocapsid

question

phospholipid bilayer w/ embedded glycoproteins surrounding the capsid in enveloped virus

viral membrane

answer

envelope

question

complete infectious viral structure: nucleic acid plus capsid for non-enveloped virus; nucleic acid plus capsid plus envelope for enveloped virus

viral partical

answer

virion

question

ribbon like protein that forms spiral around nucleic acid (ex: tobacco)

answer

–Helical capsid-

question

many sided

answer

polyhedral

question

triangular faces

answer

icosahedral

question

combination of helical and icosahedral

answer

complex capsid

question

•The infection cycle was first worked out in bacteriophages (bacterial viruses).
•Bacteriaphages generally go thru 5 steps in replication process ending in lysis of the cell

answer

adsorbtion- bac attaches to cell
, penetration- involves injection of virus into cell DNA
synthesis- once in used to make more DNA
maturation- pieces of viruses put together
release- involves lysis or bursting of the cell

question

Viral infections are _______ within the host and _____ from one host to another

answer

disseminated

transmitted

question

antibiotic resistance, synthesis of pilus, utilization of unusual nutrients, increased virulence, toxin production, antibiotic synthesis

answer

thngs that can be transferred on plasmids

question

- live on the surface of the host
Ticks, lice

answer

Ectoparasites

question

live w/in the body of the host
Some protozoa and worms

answer

endoparasites

question

must spend part of its lifecycle in or on the host
Most parasites, plasmodium- protozoa

answer

obligate parasites-

question

free living soil fungi, but can obtain nutrients from the host
Fungi that cause skin infections

answer

Falcultative parasites-

question

tapeworms, remain in or on host once they have invaded

answer

Permanent parasites-

question

biting insects feed on host then leave (mosquito)

answer

Temporary parasites:

question

invade organisms other than normal host.
Tick invading human rather than dog or wild animals

answer

accidental parasites

question

parasites that have parasites (mosquitos that have malaria)
Vectors-agents that transmit

answer

Hyperparasitism-

question

harbors host while it reproduce sexually
Malaria- mosquito

answer

Definative host:

question

- harbor parasite during a developmental stage
human

answer

Intermediate host

question

range of different host in which parasite can mature Anopheles mosquitoes (malaria)

answer

host specificity

question

•caused by several species of Aspergillus
–¿Associated with immunodeficiency
–¿Can be invasive and disseminate to the blood and lungs
•¿Causes acute pneumonia
–¿Mortality is very high.
¿Death can occur in a matter of weeks

answer

aspergillosis

chp 11 – Microbiology – Flashcards

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