Chapter 13 Flashcards
Define a host range
What host cells a virus can infect
How do receptors determine what cells a virus and infects
By specific attachment sites and cellular functions
Define a bacteriophage
Virus that only infect bacteria
Define zoonotic
Disease that can be transmitted from animals to humans
What are examples of infections from zoonotic
Rabies
Cowpox
Anthrax
SARS
Define a virion
Complete, fully developed viral particle (infectious form of virus outside cell)
What is the capsid in a virus
Protein coat made of capsomeres subunits- that surround the core of the virus
What are the three shapes of of a virus
Helical
Polyhedral
Complex
What is capsomere
Protein subunit
What are nucleic acids in a virus
DNA or RNA
What are examples of enveloped viruses
Herpes,Mumps,Measles
What are examples of naked viruses
HPV, Polio, Rhinovirus
What is the taxonomy of viruses
Order name ends in- ales
Family name ends in- viridae
Genus name ends in- virus
Define viral species
A group of viruses sharing the same genetic information and ecological niche( host)
How are subspecies designed
By a number
Define acute infection
Burst of virus/ Virions released from infected host cells
Examples of acute infection
Polio, Ebola, Flu
Define Latent
Viral genome remains silent, can reactivate later causing a productive infection
Examples of a latent infection
Chicken pox, shingles
Define persistent( Chronic)
Gradual infection over a long period
Examples of persistent ( chronic)
HIV, Liver cancer
What are spikes
Projections from outer surface
Why are enveloped viruses harder to get rid of
Made of host cell plasma membrane
Explain the lyric cycle
Phage causes lysis and death of the host cell, cell brakes open and viruses are released
What are the phases of the lytic cycle
Attachment Penetration Biosynthesis Maturation Release
In the attachment phase of the lytic cycle what happens
Phage attaches to the host cell
In the penetration stage what happens
Phage lysozyme opens the cell wall, tail sheath contracts to force the tail core of the dna in the cell
What happens in the biosynthesis stage
Production of phage dna and proteins
What happens in the maturation stage
Assembly of phage particles
What happens in the release stage
Phage lysozyme breaks the cell wall and virions are released
What happens in the lysogenic cycle
Phage DNA is incorporated in the host DNA
Phage Conversion
Specialized transduction
Requirements for viral multiplication
Invade host cell
Take over hosts metabolic machinery
One step growth curve
Prions are
Proteinaceous infectious particles- inherited and transmissible by ingestion, transplant, and surgical instruments
What are the challenges with growing animal viruses
Trying to find a animal
What is a oncogenic virus
Virus capable of causing tumors
Examples of cancers caused by virus are
Liver cancer adult leukemia lapis’s sarcoma
Influenza virus is
Zoonose comes from animals
Enveloped virus, RNA- strand
Neuraminidase( NA)
9 subtypes about 100/ virus
Hemagglutinin HA
16 subtypes and about 500 viruses major antigen
The health related issues with the flu are
Respiratory infections, fever, cough, achy, can cause pneumatic
Why do you need to get a new flu shot each year
Evolves rapidly and many types it’s not a one pice if nucleic acid
Ebola is a
Enveloped RNA - strand virus
What is a viroid
Short piece of naked RNA, no protein coat. Only infects plants/ potato spindle tuber disease
How do prions cause disease
By conversion of a normal protein into an infectious from called ( prpsc)
How do prions do damage
Plaques of fragments of prpsc molecules form in the Brian
