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53 terms

Virus

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Picornaviridae
+ RNA virus, Enterovirus- Polio disease, Picornavirus shape, Rhinovirus- Common cold
Picornaviridae
+RNA virus, Hepatovirus- Hepatitis A, Picornavirus shape
Togaviridae
+RNA, Rubella virus- Rubella ( German measles)
Equine encephalitis virus- Equine encephalitis
Togavirus shape
Flaviviridae
+RNA, Flavivirus- Yellow fever- transmit by mosquito
Togavirus shape
Retroviridae ( 2 copies)
+RNA, HTLV-I =Adult leukemia, tumors
HIV - AIDS
Paramyxoviridae
-RNA, Morbillivirus- Measles
Paramyxorirus shape
Rhabdoviridae
- RNA, Lyssavirus- Rabies
Orthomyxoviridae ( 1 copy in 8 segments)
-RNA, Influenzavirus- Influenza A & B
9 pieces of RNA
Filoviridae
-RNA, Filovirus- Marburg, Ebola
Bunyaviridae ( 1 copy in 3 segments)
-RNA, Hantavirus- Respiratory distress, hemorrhagic fevers
Reoviridae ( 1 copy in 10-12 segments)
Double stranded RNA, Rotavirus- Respiratory and gastrointestinal infection - Reovirus shape
Adenoviridae ( linear DNA)
DNA virus, Human adenoviruses - Respiratory infection- Adenovirus shape
Herpesviridae ( linear DNA)
DNA virus, Simplexvirus- Oral and genital herpes, Varicellovirus- Chickenpox, shingles - Herpesvirus
Poxviridae
DNA virus, Orthopoxvirus- Smallpox, cowpox
Papovaviridae ( circular DNA)
DNA, human papilloma viruses- WArts, cervial and penile cancers, reovirus shape
Hepadnaviridae
DNA, Hepatitis B virus- Hepatitis B
parvoviridae ( linear DNA)
Single stranded DNA viruses, B19-Fifth disease (everythema infectiousum) in children, picornavirus.
Adsorption - 1
the attachment of viruses to host cells
Is chemical attraction. It requires specific protein recognition factors found in the phage tail fibers that bind to specific receptor sites on the host cells.
penetration-2
the entry of virions ( or thier genome) into host cells
Enzyme lysozyme present in phage tails, weakens the bacterial cell wall.
Synthesis-3
the synthesis of new nucleic acid molecules, capsid proteins, and other viral components within host cells while using the metabolic machinery of those cells
Maturation-4
the assembly of newly synthesized viral components into complete virions
Release-5
The departure of new virions from host cells. Release generally, but not always, kills (lyses) host cells
Burst time
the time from adsorption to release is called.
It varies from 20-40 minutes for different phages.
Attachment stage
Attachment of tail fibers to cell wall proteins
Attachment of spilkes, capsid or envelope to plasma membrane protein
Penetration stage
Injection of viral nucleic acid through bacterial cell wall
Endocytosis or fusion ( animal virus)
Uncoating stage
None needed on bacteriophage, Enzymatic digestion of viral proteins on animal virus
Synthesis stage
In cytoplasm- in cytoplasm RNA viruses or DNA viruses, bacterial synthesis ceased- host cell synthesis ceased, viral DNA or RNA replicated, formation of viral mRNA- same on animal virus
Viral components synthesized- viral component synthesized
Maturation stage
Addition of collar, sheath, base plate and tail fibers to viral nucleic acid containing head
Insertion of viral nucleic acid into capsid
Release
Host cell lysis- Budding ( enveloped viruses), cell rupture ( nonenvelopedviruses)
Chronic infection
Lysogeny
Latency, chronic infection, cancer
Viroids
are very different from viruses, each viroid is solely a small RNA molecule
Prions
are infectious particles made of protein. Research indicates that prions are normal proteins that become folded incorrectly
Oncogenes
are viral genes that cause host cells to divide uncontrollably
Protein
A chemical component that is found in all viruses is
Icosahedron
A common polyhedral capsid shape of viruses is a
Bacteriophages
What type of viruses contain the enzyme lysozyme to aid in their infection?
Bacteriophages
Viruses that infect bacteria are called
ectoparasites
parasites can be divided into , such as ticks and lice, which live on the surface of other organisms.
Endoparasites
such as some protoza and worms which live within the bodies of other organisms
Obligate parasites
Most parasites are, they must spend at least soem of their life cycle in or on a host
facultative parasites
are free living such some soil fungi but they obtain nutrients from a host
Permanent parasites
such as tapeworms, remain in or on a host once they have invaded
Temporary parasites
such as many biting insects, feed on and then leave their host
Accidental parasites
invade an organism other than their normal host
Hyperparasitism
refer to a parasite itself having parasites
such as mosquitoes, insect or many human parasitic diseases.
Biological vector
A vector in which the parasite goes through part of its life cycle is a
Mechanical vector
is a vector in which the parasite does not go through any part of tis life cycle during transit
definitive host
hosts are classified as ... if they harbor a parasite while it reproduces sexually
intermediate hosts
If they harbor the parasite during some other developmental stages.
Mosquito is
because parasite reproduces sexually in the mosquito.
Human is
mediate host
REservoir host
are infected organisms that makes parasites available for transmission to other hosts.
Host specificity
refer to the range of different host in which a parasite can mature.