four functions of lymphatic network to maintain fluid balance in the human body
collects H20 and solutes that drain from blood vessels
return them to the blood via lymphatic vessels
pick up absorbed fats and deliver to blood
transprot foreign material to lymph nodes for disposal
difference between plasma, interstitial fluid, and lymph
plasma - from capillaries and has gasses
interstitial fluid - blood plasma that moves out of the capillaries and 90% moves back
lymph - the remaining material that doesn’t return to capillaries
illustrate the pathway of lymph and identify the structures it passes through
thoracic duct collects lymph from below the diaphragm and the left side above the diaphragm
lymph empties into the bloodstream at the left subclavian vein
lymph originates in the lower abdomen and runs against the back wall to the neck
the right lymphatic duct collects lymph from the right side above the diaphragm, empties into right subclavian vein
describe how lymph forms
plasma leaves blood capillaries and becomes interstitial fluid
interstitial fluid increases in pressure by adding proteins
increased pressure opens lymph capillaries, releasing interstitial fluid
what causes lymph to enter the lymphatic system
pressure pushes lymph from capillaries to vessels
what causes lymph to move through the lymphatic system
skeletal muscles push lymph in the direction that valves dictate
structure of lymph nodes
packed with white blood cells
function of lymph nodes
filter foreign material out of the lymph that is traveling through with lymphocytes and macrophages
define innate immunity
defenses that are already in humans (e.g. barrier defenses like the skin)
acquired immunity
defenses that are not already in humans (e.g. B and T lymphocytes)
example of barrier defense & how it works against infection
skin - prevents diseases and germs from going into our body
example of cellular innate defenses & how it works against infection
eosinophils - damage / kill multicellular invaders / parasites
example of natural killer cells & how it works against infection
NK cells - recognize and remove disease body cells or cancerous cells
steps involved in inflammatory response
histamines are release when tissue is damaged
this triggers dilation & permeability of nearby capillaries
clotting agents & phagocytic cells are delivered to the site, causing redness, swelling, and fever to occur
observable steps of inflammation
redness, soreness, swelling
define antigen
protein labels on molecules that identifies it. antibodies can bind to it to label it
define antibody
bind to antigens to identify foreign invaders for the other components of the immune system
describe how MHCs are used in the acquired immune response
they are a group of proteins designed to display proteins on a cell’s surface for a T cell to recognize
how do macrophages contribute to the immune system
engulfs foreign invaders
how do Helper-T cells contribute to the immune system
contact B or T cells that also match the current protein antigen
secretes cytokines which activate matching B or T cells
how do Cytotoxic T cells contribute to the immune system
produced by activated T cells and directly lyse body cells
how do Plasma B cells contribute to the immune system
produced by activated B cells & attach to specific antigens & incapacitates them & mark them for phagocytosis
how do memory cells contribute to the immune system
bear receptors for the same antigen & allow them to quickly mount an immune response if infected in the future
how do antigen-presenting cells contribute to the immune system
internalizes & digests foreign antigen & display it on its surface, allowing other cells to recognize the antigen & bind to it, instigating a series of events that allows the immune system to fight the foreign antigen
describe T cell maturation (process and location)
location: thymus
process: T cells bind to antigens, which activates the T cell, allowing it to directly attack cells or produce cytokines
describe B cell maturation (process and location)
location: bone marrow
process: B cells bind to an antigen & produces clones that become plasma cells, which produce large amounts of antibodies against the antigen, while others become memory B-cells
cell-mediated response
involves the use of cytotoxic cells in defending the body
humoral-mediated response
involves the use of antibodies for defending the body
naturally acquired active immunity
gained through natural exposure to antigens. body produces its own antigens
naturally acquired passive immunity
natural, passive acquisition of antibodies by the fetus from the mother. body does not produce its own antibodies
artificially acquired active immunity
the body produces its own antibodies from the vaccines
artificially acquired passive immunity
acquisition of antibodies through injection & the antibodies only last as long as the injected antibodies last
define allergic response
hypersensitive immune response to a substance that can result in inflammation, itching, or tissue damage, but is normally harmless
antigen-presenting cell (body cell)
travel around and make sure there are no foreign antigen; if there are, they digest and present it on its surface
antigen-presenting cell (macrophages)
engulf damaged cells and cell debris and present it on its surface