Pro And Viruses Flashcards
Who originated and promoted the endosymbiosis theory and what is it
Mito from animal eukaryote cell came from mito from pro, chloroplasts from a plant cell came from chloroplasts from pro. Lynn margulis
Define subcellular
Smaller in size than normal cells
Define parasitic
Lives and/or attaches to host and uses its resources
Define intracellular
Active only within host
Virus definition
A subcellular and parasitic organism that has an intracellular life cycle and is structurally simple, but has a complex life cycle (must regulate themselves and their host)
2 common components that comprise a virus
A nucleus acids genome (either DNA or RNA) and an exterior protein capsid
Third component many animal viruses are also comprised of
A lipid envelope around capsid (enveloped)
Differentiate from a naked and an enveloped viruses
Naked don’t have lipid envelope around capsid while enveloped do
Components of a virion
The entire virus (genome and capsid) is called the virion
Explain in order the 6 stages of a viruses life cycle
- Attach to host cell
- Penetrate cell membrane/cell wall
- Uncial/release genetic material
- Replicate genetic material (using host resources)
- Assemble new virion
- Release new virion from cell
State two common strains of influenza virus
Influenza A and B
Describe characteristics of influenza virus
Enveloped with single strand RNA, genome has 8 segmented regions-promotes mutation, causes infection of respiratory tract (both upper-from vocal cords up, and lower-vocal cords down)
Explain why having 8 ssRNA promotes mutations
It’s easier to change out a section of a single strand rather than a section of a double stranded DNA
Identify initial site of infection and the cells affected by pathogens (the influenza virus)
Infects upper respiratory tract first, damages the ciliated epithelial cells
Define lumen
The central cavity of a tubular or other hollow structure in an organism or cell
Describe the subsequent sites of infection and the tissue affected by the influenza virus
Virus spreads down respiratory tract, damaging bronchial or alveolar tissue (usually stays in localized respiratory tract)
Identify influenza transmission
Spread by inhalation of aerosol droplets, very contagious
Explain why the flu is more common in winter than summer
It survives best in cool, less humid atmosphere (aka winter)
Incubation period of influenza virus
1-4 incubation period
5 common symptoms of influenza virus and period that they last
High fever and chills Severe muscle pain Weakness and fatigue Sore throats and non productive cough Loss of appetite Last 5-8 days
Explain why anti-influenza drugs are not effective after 2 days
They can’t prevent later, host-induced symptoms
Differentiate and explain 3 types of prevention from influenza viruses
Immunization-
natural immunity (acquired from prior exposure, long term)
vaccination (killed virus-flu shot: high risk groups and children, grown in eggs so not for egg allergies, strain of the year)
Vaccination (live attenuated vaccine- nasal spray, more natural protection, ages 5-50)
Identify the most common cause of the common cold and URT infections
Rhinoviruses
4 characteristics of rhinoviruses
Usually does not cause serious diseases, 100 types( host receptors are on epithelial, fibroblast, and B cells aka immune cells), can’t replicate in acidic conditions (gastrointestinal tract), resistant to drying and detergents (hard to kill outside body)
