Create an account
the first few layers of cells are dead and cannot be invaded; the living cells are small and tightly connected to each other.
is a secretion of the epithelial cells that line the respiratory, digestive, urinary, and reproductive tracts. Mucus traps pathogens. In the respiratory tract, cilia on the epithelial cells, sweep the mucus to the throat, where it is swallowed.
2nd line of defense (non-specific)
mechanisms that reduce pathogen growth or destroy pathogens that enter the cells
the release of histamines by mast cells that cause itchiness, fluid leaking from capillaries, and an increase in blood flow to the area
is the body's response to pathogen invasion; elevated temperature can slow bacterial growth and speed activity of white blood cell's
phagocitic cells (such as macrophages)
are fixed in the lungs and lymph vessels that engulf pathogens and foreign materials
chemical made by body cells infected with viruses to help nearby cells resist invasion by those viruses.
Macrophage engulfs a pathogen and displays the foreign antigens on its cell membrane receptors.
The correct helper T cell bind to the activated macrophage; the activated helper T cell releases growth chemicals.
Chemicals from helper T cells cause Cytotoxic T cells to divide. These kill infective body cells with chemicals (perforins).
The antigen-antibody complex, the dead body cell, and the dead WBC's will be engulfed by macrophages.
a protein on the surface of a pathogen or a body cell that is recognized by immune system cells.
nucleic acid core; protein; capsid
A virus is made of a _________ (center) and a _______coat called a ______.
viral nucleic acids; viral cells
A virus' nucleic acid codes for making more __________ and ____________.
a virus needs to invade a host cell to use the cell's _________ as a site for protein synthesis.
antibodies; our cells don't have cell walls
bacteria are pathogens which can be killed by medications called _________ because most of these medications work by destroying the cell walls of bacteria. These medications do not hurt our cells because ________________________.
Helper T cells, cytotoxic T cells, plasma cells, macrophages and memory B cells are a few types of _________.
phagocitic cells; defense 2
large blood cells which circulate in the lungs or in the lymph nodes, and in the fluid between cells that engulf pathogens
histamines; defense 2
chemicals made by mast cells in response to allergens or pathogens; they cause the inflammatory response
RNA to DNA
Before the viral genome can be incorporated into the host cell, it must first convert its ____ to ____. (for retrovirus)
the viral DNA is incorporated into the host's DNA and the viral DNA will not be "turned on" until triggered by a later conditions.
natural active immunity
a pathogen enters the body, infection occurs, and the immune response follows
artificial passive immunity
receiving an injection of antibodies specific to an antigen (such as antivenom)
occurs when the body's immune system begins to attack its own cells in a case of mistaken identity.
the scientist who figures out what causes a certain disease and why some people get the disease while others don't. Then they tell people how to prevent it.
Please allow access to your computer’s microphone to use Voice Recording.
Having trouble? Click here for help.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!Reload
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Please upgrade Flash or install Chrome
to use Voice Recording.
For more help, see our troubleshooting page.
Your microphone is muted
For help fixing this issue, see this FAQ.
Star this term
You can study starred terms together