Exam 2 Flashcards
Why are antiviral agents hard to develop?
There are severe side effects because replication is with host cell.
Why is the influenza virus prone to antigenic shift?
The genome allows viruses to swap and create new genes
On what viral features is the Baltimore Model of viral classification based?
Whether genome is RNA or DNA, single or double, if strand directly encodes protein.
Do HPV and HIV have the same or different tissue tropism?
They exhibit different tissue tropism.
Do HPV and HIV exhibit narrow or wide tissue tropism?
They exhibit narrow tissue tropism.
What type of organisms can viruses infect?
Viruses infect all taxonomic groups: bacteria, eukaryotes, archaea.
How does a virus obtain its envelope?
Capsid will keep the viral genome intact. The capsid is then further encased by the envelope.
Does AIDS have a cure?
No but ART treatment can keep it under control
What are the different ways viruses can evolve?
Mutation, recombination, and natural selection.
Know the difference between lytic and lysogenic bacteriophage infections.
Lytic: virulent with lysis of host cell. Lysogenic: phage genome that turns into a host cell.
With respect to viruses, what does host range refer to?
What organisms or cells are virus can effect
What are prions?
No nucleic acid, misfold of protein that causes disease, don’t have RNA or DNA.
HIV infects what type of cells?
Helper T cells.
Know the various types of white blood cells (WBCs).
Granulocytes: neutrophils (fight bacteria), eosinophils (attack parasites), basophils. Agranulocytes: lymphocytes (immune), monocytes (eat everything).
What is a phagosome?
Phagocyte eats pathogen. Traps pathogen.
What is a phagolysosome?
Phagosome fuses with lysosome. Breaks down and kills pathogen.
Be familiar with the process of inflammation and all of the players involved.
Capture white blood cell, WBC attach to protein and rolls to inflammation, protein bonds, WBC spreads.
How do NK cells identify their target cells and distinguish them from host cells?
NK cells are a type of white blood cell.
Be familiar with the various types of chemical and physical barriers to infection.
Know the function of cytokines.
Chemical messengers that help immune cells communicate.
Be able to distinguish between the components of innate and adaptive immunity.
Innate is fast and first line of response. Adaptive is slower and builds memory for future infection.
What is opsonization? What is its function?
Where antibodies coat a pathogen to make it easier to phagocyte to help them kill faster.
What type of cells phagocytose bacteria and process their macromolecules for antigen presentation?
What is an antigen?
Substance that stimulates immune response.
What type of cells secretes antibodies?
B cells recognize antigens then activate and become plasma cells. Plasma then releases antibodies.
What type of cell coordinates the humoral and cellular immune responses?
Helper T cells.
What is the function of antigen presenting cells? What is the role of MHC molecules in this process?
Present antigen to T cells to activate immune response. MHC presents to helper T cells.
Be familiar with the primary and secondary immune responses.
Primary: slow and weak. Secondary: fast and strong.
What are TLRs and what kind of macromolecules do they bind?
Proteins on immune cells that recognize pathogens. They bind to lipids, nucleic acids, and proteins.
Know EACH STEP of Phagocytosis and what happens during that step!
- Chemotaxis: phagocytes moves towards pathogen
- Phagocytes sticks to pathogen
Phagocytes takes in pathogen and makes phagosome
Phagosome fuses with lysosome
Lysosome enzyme breaks down the pathogen
Waste is released from phagocyte
Where are T cells
Thymus
Cd4
Helper T cells
Cd8
Cytotoxic T cells
Where do monocytes circulate
Blood
