bio vac bac Flashcards
Characteristics of a living thing
Reproduce, made of cells, use energy, grow/adapt, have a lifespan, respond to their environment
Viruses have what non living, and living characteristics
Non living: Are made of biological particles, don’t use energy, don’t grow or have lifespan, don’t respond to environment
Living: Do evolve, reproduce only with a host
Virus structure
capsid, nucleic acid, spikes/tail fibres
Viral specificity
- Proteins inside capsid match proteins of cells virus can invade.
- DNA of virus is more similar to its host than other types of virus.
Name virus with multiple hosts
Rabies
Cell structure is different from virus because
Virus has capsid, nucleic acid, tail fibres??
what does a virus need to replicate
a host cell
Why does lysogenic cycle make you fell sicker than the lytic cycle
The lytic cycle attacks quickly whereas the lysogenic cycle will lay dormant for years and not cause an immediate reaction while appearing healthy.
Lytic cycle can be triggered by what
- Traumatic event
- Compromised immune system
- Smoking/Poor diet
- Environmental Chemicals
Three lines of defence
First- Physical and chemical barrier
Second- Inflammatory Response
Third- Immune responce
What phagocytes engulf pathogens
White blood cells
What is an antigen
Made of white blood cells, induce an immune response in the host
Lytic Cycle Steps
- Attachment and entrance: Virus recognizes host cell and attaches to it. Whole Virus or nucleic acid, enters the cell.
- Synthesis of proteins and nucleic acid: Viruses rewire the hosts machinery to replicate its own nucleic acids, enzymes, capsid proteins, and other viral proteins.
- Assembly: The viral units assemble into new viral particles
- Lysis: Host cell explodes and releases the new viral particles. Can take place in 25-45 minutes.
Lysogenic Cycle Step
- Virus does not kill or cause immediate infection
- DNA/RNA is replicated along with the host cell DNA
- coexists with host cell for many cycles while appearing healthy
- Trigger will activate viral DNA to start lytic cycle such as: traumatic event, compromised immunes system, smoking, environmental chemicals
Symptoms of inflammatory response
Swelling, redness, pain in area of infection
Non specific, and specific lines of defence
1st, 2nd: Non specific
3rd: Specific
Proteins secreted by lymphocytes
Antibodies - attach to pathogens so phagocytic cells can recognize and destroy
Interferons - coat non-infected cells; mask proteins on cell membranes
Interleukins - activate other white blood cells to fight infection
What are vaccines made of
Solutions prepared from viral components or inactivated viruses
Vaccines protect us with
Passive Immunity - injection of antibodies; short lived ability to fight infection
Active Immunity - live micro organisms that have been cultivated under conditions that disable their virulent properties
Stimulate production of antibodies