Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
51 Cards in this Set
- Front
- Back
How big is a virus? |
50-100 um |
|
Viruses are ___________ than Bacteria |
Smaller |
|
Viruses called ______________ can infect and set in motion a __________ takeover of bacteria |
bacteriophages, genetic |
|
The viruses use the cell as a viral factory? T/F |
T |
|
Virus comes from the latin word ___________ |
Poison |
|
In two decades HIV has killed ___________ people |
25 million |
|
Place in order of smallest to largest: atom virus bacteria small molecule protein |
atom, small molecule, protein, virus, bacteria |
|
How were viruses discovered? |
When they passed the bacterial solution through a filter and they inject rabbits who still got infected. |
|
What is the ratio of RNA:DNA based viruses?
|
50:50
|
|
What are a couple of the main features of viruses? |
* Have a docking mechanism to attach to cells * Can be RNA or DNA and single or double stranded * Totally dependant on living cells * Can takeover once inside |
|
What is a virion? |
They are the ones that float around looking for new hosts to infect. |
|
What is seropositivity? |
Antibodies measurement - measured as get older- increases |
|
Virions acquire an __________ during maturation through a process termed ___________ - from cellular membranes |
envelope, budding, |
|
No envelope = __________________ |
naked virus |
|
What are the 2 types of proteins in the envelope that a viral coded? |
Glycoproteins (Spikes) matrix Protein (Helical) |
|
Enveloped Viruses are released by _______ and cell __________ |
budding, lysis |
|
Enveloped viruses are environmentally sensitive to? |
acid, detergent, desiccation, heat |
|
Enveloped Cells modify Host _______________ ______________ during replication |
Cell membrane |
|
What are some of the downfalls of these enveloped features? |
Must be in moist enviro Cannot survive in GIT Doesn't always kill cell |
|
Naked Capsids are environmentally stable against: |
acids, temp, proteases, detergents, dessication |
|
What are the consequences of a naked virus? |
easy spread retain infectivity after drying resist detergent survive in GIT resist sewage treatment |
|
What are the 2 architecture of visions? |
Sphere and Helical |
|
Sphere is normally in the form of an ________________ |
isocahedron |
|
Why is a sphere great? |
best way of protecting strong structure that uses min energy |
|
What shape is a helical virus? |
cylindrical |
|
Several RNA viruses undergo self assembly as a __________ _____________. |
cylindrical nucleocapsid. |
|
The viral ______ forms a spiral within the __________ structure |
RNA, capsid |
|
Each ____________ consists of a single protein |
capsomer |
|
All animal viruses with __________ symmetry have a lipid envelope |
helical |
|
An ICOSAHEDRON is composed of ____ facets, each an equilateral ___________, and ____ vertices (corners) |
20, triangle, 12 |
|
IN the icosahedron, Because of the axes of rotational symmetry is said to have _:_:_ symmetry |
5:3:2 |
|
How are viruses named? |
DNA or RNA > envelope or naked > helical or icosahedral |
|
What system of naming is most important in viruses? |
Family |
|
What is replication? |
Copy genome |
|
What is transcription? |
copy genome to make RNA |
|
What are the 4 types of polymerase? |
RdRp RT DdDp DdRp (not viral) |
|
Routes of entry of viruses include: |
Skin/Wounds Mucosal Blood vertical Respiratory enteric sexual milk transplant |
|
What has a short incubation period? |
Enterovirus Common cold flu arbovirus |
|
What virus has a medium incubation period? |
Polio,
measles mumpsrubella varicella |
|
Long incubation periods?
|
Hep a Hep b Rabies mononucleosis |
|
Very Long incubation |
SSPE Cruetzfeldt-jakobs |
|
Mechanism of viral disease production include, 1) Cell _______ 2) Interference with the __________ of essential cells 3) Body’s response to deal with cell ___________. 4) Rashes 5) Fever 6) Triggering autoimmune response – post-infectious ____________________. |
1) Death 2) function 3) damage 6) encephalomyelitis |
|
pro-inflammatory cytokines cause _______, ________ and __________ |
Fever Rash Malaise |
|
unrestricted viral _____________ can directly cause death of cells eg neurones |
replication |
|
CTL mediated _______ of infected cells can cause damage to the organ |
lysis |
|
high levels of _________-_________ complexes can cause kidney disease |
antigen- antibody |
|
Viral replication within a cell produces visible effectsor appearances known as _____________ __________ (____) |
cytopathic effects (CPE) |
|
CPE - Cytopathic effects include: |
Cell Lysis Cell fusion Inclusion bodies = aggregation of visions Transformation |
|
Acute non-persistent infections have either a: |
Rapid Recovery (flu) or Rapid Death (rabies)
|
|
Persistent infection with acute onset have a: |
Symptom free period ( herpes) Long Symptom free followed by death or illness ( EBV, HIV) Chronic disease (HCV, HBV) |
|
Why are persistent infections important? |
Reactivation Cause chronic or progressive disease Tumours Confusion of diagnosis |