Term
DNA is a double stranded helical structure.
It is composed of nucleotides.
Each nucleotide is a |
|
Definition
| phosphate, a sugar (deoxyribose), and a nucleotide base. |
|
|
Term
The components of DNA bind together in a very specific way.
This permits a ____ and ______ orientation of the nucleotide |
|
Definition
|
|
Term
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. |
|
Definition
3' hydroxyl group
5' hydroxyl group |
|
|
Term
adenine and guanine
are large double-ring structures |
|
Definition
DNA has two types of base
Purines |
|
|
Term
thymine and cytosine
have smaller single ring structures. |
|
Definition
DNA has two types of base
Pyrimidines – |
|
|
Term
DNA STRUCTURE:
the strands are ____
one strand is orientented upsidedown relative to the other |
|
Definition
|
|
Term
DNA is a chemically stable molecule.
Any mismatched pairing is |
|
Definition
|
|
Term
is ususally found in single strand form
contains ribose |
|
Definition
|
|
Term
| helps maintain the proper shape of ribosomes. |
|
Definition
|
|
Term
| contains information derived from DNA (the messenge from the DNA that says this is what you make) |
|
Definition
|
|
Term
| –carries amino acids to ribosomes |
|
Definition
|
|
Term
how DNA is copied
incrediably accurate and fast
critical cellular process |
|
Definition
|
|
Term
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). |
|
Definition
|
|
Term
Strands must be uncoiled, unwound, and separated before replication.
This is accomplished by two enzymes: |
|
Definition
| topoisomerase and helicase |
|
|
Term
–unwinds the supercoils
unwinds the supercoils by breaking the DNa so the supercoil relaxes, and then resealing the break |
|
Definition
|
|
Term
| –once the supercoiling has been relaxed this enzyme separates and unwinds the strands |
|
Definition
|
|
Term
would produce two copies that each contained one of the original strands and one new strand.
cause you are conserving half |
|
Definition
| semiconservative replication |
|
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Term
| There are two requirements for replication: |
|
Definition
An ample supply of each of the nucleotides adenine, thymine, cytosine, and guanine
A primer: template junction |
|
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Term
| ( a sequence that tells replication to begins/ you have to have a starting point for replication) |
|
Definition
| A primer: template junction |
|
|
Term
| eacxh single strand of DNA is a |
|
Definition
|
|
Term
| a portion of DNA is paired w/ a short piece od RNA called a ________ |
|
Definition
|
|
Term
|
Definition
| unidirectional (preceeds in one direction) |
|
|
Term
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 |
|
Definition
| the primer:template junction |
|
|
Term
DNA REPLICATION:Direction
Elongation of the bases is from the 3’ end
This is required for |
|
Definition
|
|
Term
| The binding of a new base uses energy released from |
|
Definition
|
|
Term
DNA replication is performed this enzyme
forms new strands of DNA using the primer: template junction as a guide. |
|
Definition
|
|
Term
aids in accurate replication
takes place @ the primer:template junction active site |
|
Definition
|
|
Term
| with proofreading improperly paired bases are removed by an _____ (cuts out a nucleotide) |
|
Definition
|
|
Term
the double helix is unwound and seperated here
DNA rep occurs here |
|
Definition
|
|
Term
| The separated strands at the replication fork are anti-parallel and are identified as: |
|
Definition
| leading strand and the lagging strand |
|
|
Term
The leading strand is in the correct orientation for bases added to the 3’ end of the primer: template junction.
Replication moves towards the |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
each _____ has its own short RNA primer.
It is created by an RNA polymerase called primase. |
|
Definition
|
|
Term
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- |
|
Definition
|
|
Term
| (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) |
|
Definition
|
|
Term
INITIATION AND TERMINATION OF REPLICATION:
Initiation begins at a specific site on the chromosome: the _________ |
|
Definition
|
|
Term
INITIATION AND TERMINATION OF REPLICATION:
Termination occurs when the entire chromosome has been |
|
Definition
|
|
Term
INITIATION AND TERMINATION OF REPLICATION:
Replicated chromosomes are separated by ________ |
|
Definition
|
|
Term
always read in one direction
The message is translated in a fixed reading frame
There is no overlap or gap in the code |
|
Definition
|
|
Term
| a segment of DNa that codes for a functional product |
|
Definition
|
|
Term
is the production of the functional product
two features:
it involves specific interactions between DNA and RNA
it is highly regulated |
|
Definition
|
|
Term
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). |
|
Definition
|
|
Term
| three steps to stranscription |
|
Definition
| initiation elongation and termination |
|
|
Term
RNA polymerase unwinds strands of DNA and synthesizes the RNA:
It also re-anneals the strands( it puts the strands back together). |
|
Definition
|
|
Term
a sequence of DNA signals the end of transcription:
RNA polymerase detaches from DNA |
|
Definition
|
|
Term
a DNA sequence called the promoter initially binds the RNA polymerase:
This produces a bubble in the DNA. |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
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 |
|
Definition
| An open reading frame (ORF) |
|
|
Term
mRNA in translation:
mRNA contains a segment that recruits the ribosomal subunits.
Ribosome and mRNA bind here through _______ |
|
Definition
| complementary base pairing |
|
|
Term
tRNA in translation:
Each tRNA attaches to a specific amino acid at the __________ |
|
Definition
|
|
Term
It brings amino acids to the ribosome.
It binds to the ribosome at the anti-codon region using complementary base pairing |
|
Definition
|
|
Term
| The ribosome is a honeycombed structure with tunnels. The components of protein synthesis enter these tunnels and move through them. ___ ________ ___________ |
|
Definition
| mRNA tRNA Growing polypeptide chain |
|
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Term
|
Definition
| initiation elongation and termination |
|
|
Term
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. |
|
Definition
| initiation in translation |
|
|
Term
, 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. |
|
Definition
elongation:
after initiation |
|
|
Term
| in elongation the ________ moves along the mRNA |
|
Definition
|
|
Term
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. |
|
Definition
|
|
Term
| during termination the peptide achain is released from the ribosome and begins to form ___________ and __________ structures |
|
Definition
|
|
Term
is energetically expensive and highly regulatied:
constituative genes
repressible genes
inducible genes |
|
Definition
regulation of gene expression:
protein synthesis |
|
|
Term
| Some genes are on and can be turned off – (can turn off when need to). |
|
Definition
|
|
Term
| Some genes are always turned on – (always on). |
|
Definition
|
|
Term
| Some genes are off and can be turned on –(can be turned on when needed) |
|
Definition
|
|
Term
Gene expression is controlled by regulatory proteins:
_______. _____, |
|
Definition
|
|
Term
Gene expression is controlled by regulatory proteins:
_______. _____, |
|
Definition
|
|
Term
nvolved in positive regulation
DNa binding protein |
|
Definition
|
|
Term
invovlved in negative regulation
are DNA binding protein |
|
Definition
|
|
Term
| Regulatory proteins recognize two sites on DNA near the genes they control. |
|
Definition
| the promoter and the operator |
|
|
Term
| where the RNA polymerase binds. is adjacent to the operator |
|
Definition
|
|
Term
| where regulatory proteins bind. adjacent to the promoter |
|
Definition
|
|
Term
turns on genes that are off (repressed).
The best example is the lac operon: |
|
Definition
|
|
Term
an _____ is a set of genes that is regulated.
There are many in the chromosome |
|
Definition
|
|
Term
The lac system has two regulatory proteins
Both proteins bind at the operator site on DNA |
|
Definition
| the lac repressor and the lac activator- CAP (caraboilte activator protein) |
|
|
Term
is always produced.
It binds at the operator site and overlaps part of the promoter site |
|
Definition
|
|
Term
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 _______ |
|
Definition
|
|
Term
also binds at the operator site
It recruits RNA polymerase to the site.
It then interacts with the polymerase so it binds properly |
|
Definition
|
|
Term
For the genes of the lac operon to be turned on, the repressor must first be _____
occurs through an allosteric control mechanism |
|
Definition
|
|
Term
| it then interacts w/ the polymerase so it binds properly |
|
Definition
expression of lac Operon:
allosteric control mechanism |
|
|
Term
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. |
|
Definition
|
|
Term
the expression of the lac gene is leaky:
Lactose is converted to ______.
_______ binds the lac repressor. |
|
Definition
|
|
Term
The expression of lac genes is leaky
A few transcripts are made and there is always a low level of β-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 _________________________________ |
|
Definition
| can no longer bind to the operator site |
|
|
Term
acts in a similar fashion to allolactose.
Its activity is based on levels of cyclic AMP (cAMP). |
|
Definition
|
|
Term
| When cAMP levels rise, cAMP binds to ____ |
|
Definition
|
|
Term
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 |
|
Definition
3 dimensional
lac operon
promoter site |
|
|
Term
When cAMP levels fall, ___________
RNA polymerase does not bind to the promoter site.
The lac genes are not expressed |
|
Definition
|
|
Term
There are also cellular mechanisms that turn off genes.
This is very important for the conservation of energy.
has similar mechanisms to feedback inhibition |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
are changes in the DNA sequence.
Change in DNA sequence can cause changes in proteins.
so they must be kept to a minimum |
|
Definition
|
|
Term
simplest mutation
one base switched for another |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
rates are low
certain sections oof the chromosome have higher rate (hot spots) |
|
Definition
|
|
Term
can reverse the primary mutation
instead of making a faulty protein you dont make a protein @ all |
|
Definition
|
|
Term
by:
Hydrolysis
Deamination
Chemical mutagens
Alkylation
Oxidation
Base analogs
Radiation |
|
Definition
|
|
Term
| cause double-strand breaks in DNA. |
|
Definition
| gamma radiation and ionizing radiation |
|
|
Term
causes DNA damage through the formation of thymine dimers.
(big gap skipping 2 nucleotides/ reading frame mutations) |
|
Definition
|
|
Term
| damage to DNA that prevents replication |
|
Definition
|
|
Term
look like DNA bases but aren’t.
They can be mistakenly used in replication.
This inhibits further replication. |
|
Definition
|
|
Term
| what are the 3 principle mechanisms of DNA repair |
|
Definition
| nucelotide excision, base excision and photoreactivation |
|
|
Term
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 |
|
Definition
|
|
Term
•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 |
|
Definition
| nucleotide excision repair |
|
|
Term
•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. |
|
Definition
|
|
Term
| bacteria shuffling genes occurs by: transposition, transformation, conjugation, and transduction |
|
Definition
|
|
Term
| genetic recombination that takes place w/in the same cell |
|
Definition
|
|
Term
genetic recombination that takes place between cells:
______ __________
_____ |
|
Definition
| transformation, conjugation and transduction |
|
|
Term
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 |
|
Definition
|
|
Term
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. |
|
Definition
|
|
Term
| involves the shift of genetic material between cells. It involves naked DNA. |
|
Definition
|
|
Term
| is taken up by a bacterial cell and recombines with genes of that cell |
|
Definition
|
|
Term
| 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 |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
| There are two forms of transduction: |
|
Definition
generalized- random
specialized- specific |
|
|
Term
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 |
|
Definition
| There are three phases to generalized transduction. |
|
|
Term
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. |
|
Definition
| During specialized transduction: |
|
|
Term
| Specialized transduction is used in |
|
Definition
|
|
Term
involves the transfer of material between cells.
requires direct contact between the donor and recipient cells.
DNA moves from the donor to recipient cell |
|
Definition
|
|
Term
conjugation requires direct contact between the donor and reciepient cells
______ stick together
______ use pili as a conduit for DNA transfer |
|
Definition
gram positive cells
gram negative cells |
|
|
Term
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. |
|
Definition
| There are several steps in conjugation: |
|
|
Term
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 |
|
Definition
| There are several steps in conjugation: |
|
|
Term
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. |
|
Definition
|
|
Term
Conjugation:
___________ from Hfrcan be moved into a new recipient.
This replaces sections of the host chromosome |
|
Definition
|
|
Term
| mechanisms are involved in making pathogens more dangerous. |
|
Definition
|
|
Term
| is closely associated with pathogenicity and virulence. It transfers virulence genes into bacteria that were previously harmless. |
|
Definition
|
|
Term
| Genes for antibiotic resistance and toxins are found on |
|
Definition
|
|
Term
| Genes for resistance to disinfectants and environmental pressure are found on |
|
Definition
|
|
Term
| 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 |
|
Definition
|
|
Term
|
Definition
Bacteria (called bacteriophages)
Plant cells
Animal cells (human cells included in this group). |
|
|
Term
|
Definition
|
|
Term
| is surrounded by a protein coat called a capsid. |
|
Definition
|
|
Term
| each is made up of capsomeres |
|
Definition
|
|
Term
| there are 2 types of viuses |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
| have specific nomenclature |
|
Definition
|
|
Term
•It is built from identical protein units called capsomeres.
–¿Capsomeres bond together and give the _______ structural symmetry.
–¿Viruses possess either helical or icosahedral symmetry |
|
Definition
|
|
Term
| viruses possesss either ____ or _____ symmetry |
|
Definition
|
|
Term
| There are two shapes of helical viruses: |
|
Definition
Rod –straight and relatively rigid
Filamentous –flexible, curved, or coiled. |
|
|
Term
Their shape is derived from 20 triangular faces that make up the capsid
2 types:
simple and complex |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
|
Definition
Size
Morphology
Complexity
Composition |
|
|
Term
envelope glycoproteins are firmly embedded in the envelope bilayer
this is facilitated by domains of host membrane proteins called |
|
Definition
|
|
Term
| envelope glycoproteins can form spikes or other structures on the outside of the virion which can be used to attach to the |
|
Definition
|
|
Term
important in infection
packaged either:
directly in the capsid
enclosed in special proteins
or enclosed in proteins from the host cell |
|
Definition
|
|
Term
the host cells fills with virions and bursts.
The result is cell death. |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
| For animal viruses, there are six steps in lyticinfection: |
|
Definition
Attachment
Penetration
Uncoating
Biosynthesis
Maturation
Release |
|
|
Term
| occurs when a virion binds to specific receptors on a host cell |
|
Definition
|
|
Term
in virion attachment some viruses require a _______ to attach.
without it theres no infection |
|
Definition
|
|
Term
interactions occur through random collisions.
The number of viruses is extremely important. |
|
Definition
|
|
Term
WHEN VIRUS MEETS HOST CELL:
produce the maximum number of virions |
|
Definition
|
|
Term
must be permissive for the infection to succeed.
It must contain all of the components required to make new virions. |
|
Definition
|
|
Term
at the apical cell surface usually cause acute infection.
at the basolateral cell surface can become systemic |
|
Definition
|
|
Term
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. |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
is high affinity.
There are conformational interactions. |
|
Definition
|
|
Term
| Binding takes place between viral capsid and receptor. |
|
Definition
|
|
Term
| Binding takes place between viral envelope proteins and receptor |
|
Definition
|
|
Term
Once attached, the virus must gain entry to the host cell.
It must also ______ or _______ the capsid. |
|
Definition
|
|
Term
| Uncoating can occur in three places: |
|
Definition
the plasma membrane
in the cytoplasm
@ the nuclear membrane |
|
|
Term
| Use receptor mediated endocytosisto gain entry into the host cell |
|
Definition
| PENETRATION & UNCOATING: Non-enveloped Viruses |
|
|
Term
| Virus is enclosed in a vesicle –the early endosome Early endosomesfuse with or become late endosomes. Late endosomesfuse with the lysosomewhere uncoatingbegins. |
|
Definition
receptor mediated endocytosis:
non enveloped viruses |
|
|
Term
| some viruses pore in the host membrane |
|
Definition
| PENETRATION & UNCOATING: Non-enveloped Viruses |
|
|
Term
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 |
|
Definition
| PENETRATION & UNCOATING: Enveloped Viruses |
|
|
Term
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 |
|
Definition
|
|
Term
Viral infection requires compartmentalization.
Newly synthesized viral components are moved to other locations for assembly of __________ |
|
Definition
|
|
Term
Viral components are moved in vesicles, using host cell ________.
Specialized host cell proteins are sometimes used. |
|
Definition
|
|
Term
DNA viruses use routine host cell _____ to cross the nuclear membrane.
The pathways form pores in the nuclear membrane |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
are either DNA or RNA.
Both can be single or double-stranded. |
|
Definition
|
|
Term
| 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 |
|
Definition
| Double-stranded DNA Viruses |
|
|
Term
| is used as a template to make a complementary copy of DNA. |
|
Definition
|
|
Term
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 __________ |
|
Definition
DNA polymerase
complementary copy
viral genome |
|
|
Term
requires:
The synthesis of at least one viral protein
The expression of several viral genes. |
|
Definition
| BIOSYNTHESIS: Replication of DNA Virus Genomes |
|
|
Term
| has the same configuration as host DNA. |
|
Definition
|
|
Term
| is performed by the host cell machinery |
|
Definition
| replication of Dna virus genomes |
|
|
Term
| viruses require much less DNA replication. |
|
Definition
|
|
Term
| synthesis is inhibited by the virus. All polymerases and proteins concentrate on viral DNA synthesis. |
|
Definition
|
|
Term
form in the host cell –replication compartments
They contain both DNA templates and host cell replication machinery.
They are essentially viral factories. |
|
Definition
|
|
Term
| allows exponential viral replication |
|
Definition
|
|
Term
| 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 |
|
Definition
| BIOSYNTHESIS:Replication of Latent DNA Viruses |
|
|
Term
Newly made viral DNA molecule is used as the template for
is performed by the host cell’s RNA polymerase. |
|
Definition
|
|
Term
| expression begins after DNA synthesis. Genes are expressed in a specific order. |
|
Definition
| transcription: viral gene |
|
|
Term
| Transcription with single-stranded DNA viruses is more complicated. The single DNA strands must first be converted to |
|
Definition
|
|
Term
| Viral genes are transcribed at very high rates. This maximizes the number of |
|
Definition
| new viruses being produced |
|
|
Term
| 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. |
|
Definition
|
|
Term
| Mechanisms of biosynthesis are more complicated than in DNA viruses. Host cells do not possess RNA-dependent polymerases. |
|
Definition
|
|
Term
| They are required to make viral mRNA and replicate genomes. Viruses must carry one |
|
Definition
| RNA-dependent polymerases. |
|
|
Term
| are RNA viruses that contain the enzyme reverse transcriptase. cause latent infections. |
|
Definition
|
|
Term
| converts RNA into DNA. Converted viral DNA can be inserted into the host cell _________ |
|
Definition
reverse transcriptase
chromosome |
|
|
Term
| Involves the movement of newly made viral components to specific sites in the host cell. |
|
Definition
|
|
Term
| There are two steps in maturation: |
|
Definition
| Intracellular trafficking Assembly |
|
|
Term
| 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. |
|
Definition
| Intracellular Trafficking |
|
|
Term
| depend on: The type of genome (DNA or RNA) The mechanism of genome replication The presence or absence of an envelope |
|
Definition
|
|
Term
| in intracellular trafficking many _______ viruses assemble near the host cell membrane Others assemble near membrane bound organelles. |
|
Definition
|
|
Term
| in intracellular tafficking these viruses assemble in the host cell nucleus |
|
Definition
|
|
Term
| in intracellular traffiking travel from the assembly site to the cell membrane in vesicles. |
|
Definition
|
|
Term
| in intracellular trafficking _____ transport depends in whether the virus has an envelope |
|
Definition
|
|
Term
| in intracellular traficking ___________ genomes move to sites near the membrane |
|
Definition
|
|
Term
| in intracellular trafficking ________-genomes move to the host cell nucleus. |
|
Definition
|
|
Term
| 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. |
|
Definition
|
|
Term
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.
|
|
Definition
|
|
Term
| 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. |
|
Definition
|
|
Term
| can be assisted by host chaperone proteins. |
|
Definition
|
|
Term
| ASSEMBLY: Viral Genomes This is the most important part of assembly. There are two mechanisms: |
|
Definition
| Concerted assembly and sequential assembly |
|
|
Term
| –the viral genome is inserted into already assembled capsid |
|
Definition
|
|
Term
| –the virion is assembled while the viral genome is being synthesized |
|
Definition
|
|
Term
| New virions can be released from the host cell in two ways: |
|
Definition
|
|
Term
| Non-enveloped viruses use _ forr release. This causes death of the host cell. |
|
Definition
|
|
Term
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). |
|
Definition
|
|
Term
| release: In some viral infections, ________ are non-infectious. Viral enzymes convert them into an infectious form after release. |
|
Definition
|
|
Term
| can spread from cell to cell. They can use tight junctions between cells. They can also spread through the formation of syncytia. |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
| spread: Some viruses produce _____: These are empty capsids or non-infectious virions They confuse and distract the host defenses. |
|
Definition
|
|
Term
| spread: Some viruses incorporate host proteins as a type of |
|
Definition
|
|
Term
can be:
Acute (rapid and self limiting)
Persistent (long term)
Latent (extreme versions of persistent infections)
Slow or transforming (complicated types of persistent infections) |
|
Definition
|
|
Term
| produce virions and kill host cells rapidly (cytopathology |
|
Definition
|
|
Term
| viruses produce virions but do not cause cytopathology |
|
Definition
|
|
Term
| me viruses dont produce virions or cause cytopathology but |
|
Definition
|
|
Term
periods vary for different viruses.
Some are as short as days.
Some are as long as years. |
|
Definition
|
|
Term
during the incubation period the virus is ______
the host is beginning to ______ |
|
Definition
|
|
Term
|
Definition
|
|
Term
rapid production of virions & elimination of infection;
virions can be missed and spread to other tissues
this then causes reinfection
ex: varicella-zoster |
|
Definition
|
|
Term
severe public health problem
associated w/ epidemics
short incubation period
which causes a delay in indentifiable symptoms until the virus has already spread |
|
Definition
|
|
Term
| Acute infection epidemics are often seen in |
|
Definition
crowded populations.
Schools
Military bases
Nursing homes |
|
|
Term
hosts that survive acute infections are immune to __________ for life:
some diseases escape this immunity |
|
Definition
|
|
Term
(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 |
|
Definition
|
|
Term
| there are 2 forms of antigenic variation |
|
Definition
| antigenic drift and antigenic shift |
|
|
Term
Involves major changes in virion structure
Is due to the acquisition of new genes
This is through co-infection or recombination |
|
Definition
|
|
Term
Involves small changes in virion structure
Results from mutations
Occurs after the infection has begun |
|
Definition
|
|
Term
Caused when host defenses are either modulated or completely bypassed.
Virions are produced for months or even years. |
|
Definition
|
|
Term
| There are two variations of persistent infections |
|
Definition
| chronic and latent infection |
|
|
Term
| the infection lasts for life |
|
Definition
|
|
Term
| the infection is eventually cleared |
|
Definition
|
|
Term
host defense mech against viral infec
They must be given the signal to begin killing infected cells.
Some viruses can kill them first. |
|
Definition
|
|
Term
| some viruses escape killing by infecting tissues that have reduced immunosurveillance |
|
Definition
skin
central nervous system |
|
|
Term
No large-scale production of virions
Reduced or absent immune response
Persistence of an intact viral genome so infections can reoccur |
|
Definition
|
|
Term
| can be reactivated years after entry into host. |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
| Sufficient number of viruses present Access to susceptible and permissive host cells An ineffective host immune response |
|
Definition
| There are three basic requirements for successful infection |
|
|
Term
| are disseminated within the host and transmitted from one host to another. |
|
Definition
|
|
Term
refers to spread of virus within an infected body.
There are common sites for viruses to enter into the body. |
|
Definition
|
|
Term
| what are the three main entry points for viral dissemination |
|
Definition
| respiratory system, digestive system and the urogenital tract |
|
|
Term
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 |
|
Definition
|
|
Term
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. |
|
Definition
|
|
Term
in the digestive tract some viruses use transcytosis through _______ to enter the body
some viruses stay in the _____ and eventually destroy them |
|
Definition
|
|
Term
| their destruction causes inflammation of the digestive tract and diarrhea |
|
Definition
|
|
Term
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. |
|
Definition
|
|
Term
viruses also use this
like when they enter through the eyes
ex: opthalmic herpes infection |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
They can disseminate throughout the entire body.
Some target neurons.
Some use neurons to get to their preferred target area. |
|
Definition
| viral dissemination in the nerous system |
|
|
Term
| Viruses released from the apical surface host cells cause |
|
Definition
| localized limited infection |
|
|
Term
| Viruses released from the basement membrane of host cells can |
|
Definition
|
|
Term
The bloodstream is the best route for systemic viral infection.
Referred to as |
|
Definition
| hematogenous dissemination |
|
|
Term
| refers to virus replicating in the blood |
|
Definition
|
|
Term
| refers to the spread of the virus from one host to another |
|
Definition
|
|
Term
there are 2 patterns of viral transmission
human to human ?
and animal to human? |
|
Definition
transmission w/ in a single species
transmission between species |
|
|
Term
Viruses can be transmitted in several ways:
Via _____ or inanimate objects
Via poor techniques employed by health care workers: ___________
________ –the digestive tract |
|
Definition
fomites
iatrogenic transmission
Fecal-oral route |
|
|
Term
Viruses can be transmitted in several ways:
Respiratory tract ?
Viruria ?
Urogenital tract ?
Contact with ? |
|
Definition
the sneeze is the best form of transmission
transmission via urine
sexual transmission
skin |
|
|
Term
infections are seasonal.
Respiratory tract infections are higher in winter.
Digestive tract infections are higher in summer. |
|
Definition
|
|
Term
| in pregnant women can expose the fetus to infection |
|
Definition
|
|
Term
| some virus transmission from mother to infant can occur through |
|
Definition
|
|
Term
| the capacity of an infectious organsim to cause disease |
|
Definition
|
|
Term
| viruses can cause significant damage |
|
Definition
|
|
Term
| (attenuated) viruses cause little or no disease. |
|
Definition
|
|
Term
| –how much virus is required to paralyze 50% of a subject population. |
|
Definition
| PD50 (way to measure viral virulence ID50 & LD50 as well) |
|
|
Term
can be directly affected by:
Route of entry
Age and health of host
The gender of the host |
|
Definition
|
|
Term
Susceptible –can be infected and can also transmit the infection
Immune –cannot be infected |
|
Definition
| There are two types of host: |
|
|
Term
| caqn gender play a role in infection? |
|
Definition
| Males are more susceptible to viral infection than females. |
|
|
Term
the most effective way to deal with viral infections.
It allows for life-long immunity from a particular infection.
It increases herd immunity |
|
Definition
|
|
Term
| what are the 3 groups of vaccines |
|
Definition
live attenuated cavvine
inactivated or killed vaccine and subunit vaccine |
|
|
Term
| made of intact virions rendered non-infectious |
|
Definition
|
|
Term
| composed of killed or dead virons |
|
Definition
| inactivated or killed vaccine |
|
|
Term
| cposed of immunogenic parts of virions |
|
Definition
|
|
Term
| antigen is administered and causes the onset of the immune response |
|
Definition
|
|
Term
| a preformed antiviral product, such as antibody, is administered |
|
Definition
|
|
Term
| can inactivate genes responsible for suppressing tumor formation. |
|
Definition
|
|
Term
Some viruses can cause _____ in animals.
An estimated 20% of human ______ involve viruses |
|
Definition
|
|
Term
| Viruses associated with human cancers include: |
|
Definition
Epstein-Barr virus
Hepatitis B and C viruses
HPV |
|
|
Term
for many products that modify or block host defense.
A battle wages between the host immune system and these modifications |
|
Definition
|
|
Term
| are usually opportunistic infections and have increased with the number of immunocompromised individuals |
|
Definition
|
|
Term
| Parasites can be divided into two groups: |
|
Definition
Protozoans – microscopic, single-celled eukaryotes.
Helminths – macroscopic, multicellular worms. |
|
|
Term
| Disease causing parasites depend on their ______ for survival |
|
Definition
|
|
Term
| are intestinal parasites that infect 10% of the world population |
|
Definition
|
|
Term
| parasites infect 16 million people in Latin America each year |
|
Definition
|
|
Term
vary in size.
They contain membrane-bound nuclei and cytoplasm. |
|
Definition
|
|
Term
| the cytoplasm of parasitic protozoans are divided into |
|
Definition
inner form- endoplasm
and outer form-ectoplasm |
|
|
Term
| parasitic protozoans can be classified on the basis of their methods of |
|
Definition
| movement and reproduction |
|
|
Term
Are facultative anaerobes
Are heterotrophs
Have a highly developed reproductive system |
|
Definition
| most infectious protozoans |
|
|
Term
| some infectious protozoans form ____ as a way of protecting themselves. they can also be a mech of transmission from host to host |
|
Definition
|
|
Term
are worms.
There are two types:
Free living
Parasitic
They are bilaterally symmetrical and of various lengths |
|
Definition
|
|
Term
parasitic helminths body is covered by a tough cellular ______
some have suckers, hooks, or plates which are used for _______ |
|
Definition
|
|
Term
Differentiated organs
Primitive nervous systems
Primitive excretory systems
Highly developed reproductive systems
They do not have a circulatory system. |
|
Definition
|
|
Term
| comes in 2 forms: gastrointestinal form and blood and tissue form |
|
Definition
|
|
Term
| use only one host to complete their life cycle |
|
Definition
| gastrointestinal form of nematodes |
|
|
Term
| uses multiple hosts to complete their life cycle |
|
Definition
| blood and tissue form of nematode |
|
|
Term
| what are the three types of helminth that can infect humans |
|
Definition
| cestodes (tapeworms), trematodes (flukes), nematodes (round worms) |
|
|
Term
| 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. |
|
Definition
|
|
Term
| Have leaf-shaped bodies They have two suckers. Oral sucker –takes in nutrients and regurgitates waste Distal sucker –used for attachment |
|
Definition
|
|
Term
| 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 |
|
Definition
|
|
Term
| can cause: Tissue damage Allergic or anaphylactic reactions |
|
Definition
| The host defense reaction |
|
|
Term
| are intracellular parasites. They alternate between sexual and asexual reproduction |
|
Definition
|
|
Term
| most important sporozoans diseases that together affect 1/3 of the world's population |
|
Definition
| malaria and toxoplasmosis |
|
|
Term
| febrile illness found worldwide transmission by bite of anopheles mosquito mortality mainly seen in children and immunocompromised adults |
|
Definition
| malaria (plasmodium species) |
|
|
Term
| Male fertilizes female gametocytes Resulting zygote forms an oocyst filled with sporozoites Oocyst ruptures releasing sporozoites into body Sporozoites penetrate salivary glands |
|
Definition
| (plamodium) Sexual life cycle begins when a mosquito ingests infected blood |
|
|
Term
| 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). |
|
Definition
| Asexual life cycle begins when a mosquito bites new host. |
|
|
Term
| 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 |
|
Definition
| life cycle of the plasmodium |
|
|
Term
| Fever Anemia Circulatory changes thrombocytopenia |
|
Definition
| Symptoms of malaria include: |
|
|
Term
| is caused by the destruction of red blood cells. It is accompanied by depression of marrow function and an enlarged spleen |
|
Definition
|
|
Term
| two factors involved in the treatment of malaria |
|
Definition
| species of plasmodium and the immunocompetency of the infected individual |
|
|
Term
| are amebas. The most primitive form of protozoans that: Multiply by simple binary fission Move by using pseudopodia. Produce a chitin wall for protection |
|
Definition
|
|
Term
| rhizopods produce a chitin wall for protection that is referred to as a |
|
Definition
|
|
Term
| 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 |
|
Definition
| AMEBIASIS (ENTAMOEBA HISTOLYTICA) |
|
|
Term
| is the third highest parasitic cause of deaths worldwide. Only malaria and schistosomiasis are higher. is on the rise in the US |
|
Definition
| amabiasis (entamoeba histolytica) |
|
|
Term
| LIFE CYCLE OF ENTAMOEBA HISTOLYTICA: It is found in either the ________ form. |
|
Definition
|
|
Term
| Initial infection is via the fecal-oral route. Systemic ________ occurs only after the colon colonized |
|
Definition
| PATHOGENESIS OF AMEBIASIS amebiasis |
|
|
Term
| pathogenesis of amebiasis the parasite produces several virulence factors and enzymes which can cause membrane ____ and _______ |
|
Definition
| lesions and cellular death |
|
|
Term
| w/ amebiasis the infection is usually mild and asymptomatic. lesions can open the intestine for _______ and __________ |
|
Definition
| bacterial and viral infection |
|
|
Term
| in amebiasis cysts can pass through the stomach and into the small intestine here they disintegrate and release four |
|
Definition
|
|
Term
| are widespread in nature. They use flagella for movement through the host. They multiply by binary fission |
|
Definition
|
|
Term
| what are the four flagellates that cause disease in humans |
|
Definition
| Trichomonas Giardia Leishmania Trypanosoma |
|
|
Term
| these 2 flagettes are noninvasive, have low morbity rates and theres no intermediate host required |
|
Definition
|
|
Term
these 2 flagellates are invasive, have high morbidity rates, are frequently lethal and required an intermediate host
(associated w/ the sandfly) |
|
Definition
| leishmania and tryanosoma |
|
|
Term
is a sexually transmitted infection.
It produces vaginitis in females with symptoms:
Pain Dysuria Discharge |
|
Definition
| TRICHOMONIASIS (TRICHOMONAS VAGINALIS) |
|
|
Term
| 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. |
|
Definition
| TRICHOMONIASIS(TRICHOMONAS VAGINALIS) |
|
|
Term
| 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. |
|
Definition
|
|
Term
| Direct contact transmission to genital endothelial cells causes the infection. Cells are destroyed and inflammation occurs. It is accompanied by petechial hemorrhaging. is noninvasive |
|
Definition
| pathogenesis of trichomoniasis |
|
|
Term
| TRICHOMONIASIS: Infection causes persistent ______. Symptoms can last for months. Severe cases can cause ________ and ________. |
|
Definition
vaginitis
hemorrhaging and tissue errosion |
|
|
Term
It is caused by the protozoan _______
Motile Fusiform Moves in a spiral fashion
The vector is the tsetse fly (Glossina species). |
|
Definition
TRYPANOSOMIASIS
Trypanosoma. |
|
|
Term
| there are 2 forms of trypanosomiasis the african form which causes ____ and the american form which causes _____ |
|
Definition
sleeping sickness
chaga's disease |
|
|
Term
| is caused by trypanosomissis and is confined to central Africa. There are ten to twenty thousand cases each year. The reservoir is humans |
|
Definition
|
|
Term
PATHOGENESIS OF TRYPANOSOMIASIS:
Parasitemia causes localization of parasites in __________ the heart and CNS are particularily vulnerable |
|
Definition
|
|
Term
PATHOGENESIS OF TRYPANOSOMIASIS
|
|
Definition
Symptoms include:
Hemorrhaging Demyelinating panencephalitis Headache Fever Lymph adenopathy Skin rash Impaired mental status |
|
|
Term
TRYPANOSOMIASIS
Symptoms can progress to: |
|
Definition
| Eventual diminished alertness. Indistinct speech, tremors, and coma. Coma can lead to death. |
|
|
Term
| what are the subgroups for nematodes |
|
Definition
| intestinal nematodes and tissue nematodes |
|
|
Term
| 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 |
|
Definition
|
|
Term
what type of nematodes are these?
Pinworms
Whipworms
Large roundworms
(eggs must incubate outside the host) |
|
Definition
|
|
Term
can produce:
Malnutrition
Discomfort
Anemia
Occasionally death |
|
Definition
| intestinal nematode infection |
|
|
Term
severity of intestinal nemotodes in directly correlated to worm load.
small worm load ?
large worm load ? |
|
Definition
| pinworm (enterobius vermicularis) |
|
|
Term
pathogenesis of enterobiasis:
pinworms attach to the mucosa of the _______
females migrate down the ___________ to lay eggs |
|
Definition
|
|
Term
| 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 ______ |
|
Definition
|
|
Term
| Tissue nematodes can induce disease in: |
|
Definition
| tissue blood and lymph systems |
|
|
Term
| Four major types of ________ use humans as definitive hosts. They can live for years in subcutaneous tissues and lymph vessels. |
|
Definition
|
|
Term
| Tissue nematodes discharge live offspring called ________. Circulate through the blood or tissue Can be ingested by blood sucking insects |
|
Definition
|
|
Term
Caused by the parasite Trichinella spiralis:
Lives in the duodenum and jejunum of flesh eating mammals. Particularly found in swine and bears |
|
Definition
|
|
Term
| 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. |
|
Definition
|
|
Term
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 |
|
Definition
|
|
Term
|
Definition
| in trichinosis ________ are nfound in striated muscle Heart muscle CNS |
|
|
Term
PATHOGENESIS OF TRICHINOSIS
The area of infection is infiltrated by white blood cells, particularly ___________.
Worms mature in 24-48 hours of eating ______ |
|
Definition
| eosinophiles tainted meat |
|
|
Term
| symptomes of trichinosis include |
|
Definition
| nausea, andominal pain and diarrhea |
|
|
Term
PATHOGENESIS OF TRICHINOSIS:
Larval invasion starts _______ later.
Lasts one to ______
Low worm load – __________
Large worm load – ________ |
|
Definition
one week
six weeks
asymptomatic
significant disease and poss death |
|
|
Term
| 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 |
|
Definition
|
|
Term
pathogenesis of cestode infec:
in the _____:
the worms stays in the lumen of the gut
only minor symptoms are seen |
|
Definition
|
|
Term
pathogenesis of cestode infection:
in the ____________:
larval stages of the worm cause serious tissue invasion most patients are asymptomatic |
|
Definition
|
|
Term
| PATHOGENESIS OF CESTODE INFECTION Symptoms include |
|
Definition
| Gastric disfunction Nausea Diarrhea Weight loss |
|
|
Term
| 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 |
|
Definition
|
|
Term
| can live for decades in human tissue and blood vessels. They produce progressive damage to vital organs. |
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Definition
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Term
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 |
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Definition
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Term
LIFE CYCLE OF TREMATODES: Miracadia develop into _______.
_______ are released from the snail. |
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Definition
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Term
DISEASE CAUSING TREMATODES
Three major groups of flukes invade humans: |
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Definition
| Lung flukes –Liver flukes –Blood flukes – |
|
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Term
| Infections are frequently caused by consuming infected shell fish Infections cause eosinophilia and inflammation. After infection a capsule forms around the fluke |
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Definition
| paragonimiasis: lung flukes |
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Term
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Definition
|
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Term
are important for the environment
are commensal organisms.
They are normally harmless to humans. can be opportunistic pathogens |
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Definition
|
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Term
| are eukaryotes. There are two forms: Molds –multicellular Yeasts –unicellular |
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Definition
|
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Term
Fungi use __________ metabolism
They obtain carbon from decaying organic matter. |
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Definition
|
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Term
| Most fungi are _______ aerobes but some are ___________ anaerobes. No fungi are _____ |
|
Definition
| obligate facultative obligate anaerobes. |
|
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Term
| Fungi reproduce either sexually or asexually. Involves spores -ascospores, zygospores, or basidiospores |
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Definition
|
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Term
| Fungi reproduce either sexually or asexually. Through conidia Involves mitotic division and budding |
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Definition
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Term
•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 |
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Definition
|
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Term
| form of fungi that requires environmental conditions similar to in vivo. Proper temperature Increased nutrients |
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Definition
|
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Term
| form of fungi requires: Ambient temperatures Minimal nutrients |
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Definition
|
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Term
| fungi are classified by: Ribosomal RNA typing The tissue types they parasitize The diseases they produce |
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Definition
|
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Term
are classified into 4 groups:
Superficial mycoses Mucocutaneous mycoses Subcutaneous mycoses Deep mycoses |
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Definition
|
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Term
| Fungal infections that do not involve a tissue response: Piedra, Tinea nigra, Tinea capitis, favus, and pityriasis |
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Definition
|
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Term
| –colonization of the hair shaft causing black or white nodules |
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Definition
|
|
Term
| brown or black superficial skin lesions |
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Definition
|
|
Term
| folliculitis on the scalp and eyebrows |
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Definition
|
|
Term
| –destruction of the hair follicle. |
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Definition
|
|
Term
–dermatitis characterized by redness of the skin and itching:
Caused by hypersensitivity reactions to fungi normally found on skin
Mostly seen in immunocompromised patients |
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Definition
|
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Term
| Associated with: Skin Eyes Sinuses Oropharynx and external ears Vagina |
|
Definition
| CUTANEOUS AND MUCOCUTANEOUS MYCOSES |
|
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Term
(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 |
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Definition
|
|
Term
| ringworm on feet or between toes |
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Definition
|
|
Term
| ringworms between the fingers, in wrinkles on the palms |
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Definition
|
|
Term
| ringworms lesions on the hairy skin around the genetalia |
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Definition
|
|
Term
| ringworms in scalp and eyebrows |
|
Definition
|
|
Term
| chronic infection of the nail bed Commonly seen in toes |
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Definition
|
|
Term
| type of cutaneous and mucocutaneous mycoses that has extended scaly areas on the hands and feet |
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Definition
|
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Term
| colonization of the mucous membranes Caused by the yeast Candida albicans Often associated with a loss of immunocompetence |
|
Definition
| mucocutaneous candidiasis |
|
|
Term
| There are two clinical types of mucocutaneous candidiasis: |
|
Definition
| thrush and vulvovaginitis |
|
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Term
| fungal growth in the oral cavity An indicator of immunodeficiency. |
|
Definition
|
|
Term
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 |
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Definition
|
|
Term
| Can cause the development of cysts and granulomas. Provoke an innate immune response -eosinophilia |
|
Definition
| localized primary infections of subcutaneous tissue |
|
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Term
| Usually seen in immunosuppressed patients with: AIDS Cancer Diabetes |
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Definition
|
|
Term
| Can be acquired by: Inhalation of fungi or fungal spores Use of contaminated medical equipment |
|
Definition
|
|
Term
| Deep mycoses can cause a systemic infection - __________ Can spread to the skin |
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Definition
|
|
Term
| very uncommon in immunocompetent individuals are more common in immunodeficient patients |
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Definition
|
|
Term
| fungi can become invasive. They switch from yeast form to mold form. The hyphae invade tissues and disseminate |
|
Definition
|
|
Term
| Fungi do not produce exotoxins in vivo. Primary ________ is due to host inflammatory response. |
|
Definition
| tissue injury in fungal infections |
|
|
Term
| Host defense against fungal infection is primarily through: |
|
Definition
| Phagocytosis Adaptive immune response |
|
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Term
| cause antibiotic resistance |
|
Definition
|
|
Term
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 |
|
Definition
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 |
|
|
Term
| protein molecule forming capsid |
|
Definition
|
|
Term
protein shell surrounding nucleic acid
protein coat |
|
Definition
|
|
Term
|
Definition
|
|
Term
phospholipid bilayer w/ embedded glycoproteins surrounding the capsid in enveloped virus
viral membrane |
|
Definition
|
|
Term
complete infectious viral structure: nucleic acid plus capsid for non-enveloped virus; nucleic acid plus capsid plus envelope for enveloped virus
viral partical |
|
Definition
|
|
Term
| ribbon like protein that forms spiral around nucleic acid (ex: tobacco) |
|
Definition
|
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Term
|
Definition
|
|
Term
|
Definition
|
|
Term
| combination of helical and icosahedral |
|
Definition
|
|
Term
•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 |
|
Definition
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 |
|
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Term
| Viral infections are _______ within the host and _____ from one host to another |
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Definition
|
|
Term
| antibiotic resistance, synthesis of pilus, utilization of unusual nutrients, increased virulence, toxin production, antibiotic synthesis |
|
Definition
| thngs that can be transferred on plasmids |
|
|
Term
- live on the surface of the host
Ticks, lice |
|
Definition
|
|
Term
live w/in the body of the host
Some protozoa and worms |
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Definition
|
|
Term
must spend part of its lifecycle in or on the host
Most parasites, plasmodium- protozoa |
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Definition
|
|
Term
free living soil fungi, but can obtain nutrients from the host
Fungi that cause skin infections |
|
Definition
|
|
Term
| tapeworms, remain in or on host once they have invaded |
|
Definition
|
|
Term
| biting insects feed on host then leave (mosquito) |
|
Definition
|
|
Term
invade organisms other than normal host.
Tick invading human rather than dog or wild animals |
|
Definition
|
|
Term
parasites that have parasites (mosquitos that have malaria)
Vectors-agents that transmit |
|
Definition
|
|
Term
harbors host while it reproduce sexually
Malaria- mosquito |
|
Definition
|
|
Term
- harbor parasite during a developmental stage
human |
|
Definition
|
|
Term
| range of different host in which parasite can mature Anopheles mosquitoes (malaria) |
|
Definition
|
|
Term
•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 |
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Definition
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