Module 9 Lymphatic System Flashcards
interstitial fluid
extracellular fluid out in the tissues; washes over the tissues delivering nutrients to the cells and washing away wastes, cellular debris, viruses, bacteria and loose cells
two collecting ducts
thoracic duct & right lymphatic duct
natural killer cells
NK Cells; large lymphocytes that are important in nonspecific defense; destroy bacteria, fight against trasplanted tissues, attack cells infected by viruses, and destroy cancer cells
T lymphocytes
T cells; migrate from red bone marrow to the thymus gland where they mature
B lymphocytes
B Cells; migrate from red bone marrow to lymphoid tissues; also functions as antigen-presenting cells (APCs) by constantly sampling material from their environment, processing it, and displaying it for other cells to see.
2 types of B cells:
B Plasma cells- produce antibodies which are dissolved proteins in plasma that seek out specific foreign antigens for their destruction
B Memory cells- remember pathogens that have been introduced to that repeat exposure can be fought more swiftly
dendritic cells
immune system cells of the epidermis that stand guard to alert the body of pathogens entering through the skin; also function as APCs
mucosa-associated lymphatic tissue
MALT; scattering of lymphocytes located throughout the mucous membranes lining tracts to the outside environment, such as the tracts for the digestive, respiratory, urinary, and reproductive systems; stands guard against any pathogens trying to enter the body
Peyer’s Patches
patches of lymphatic tissue located at the distal end of the small intestine; example of more densely packed pockets of lymphocytes called nodules
lymph nodes
remove anything that may be potentially harmful in lymph; packed with lymphocytes and macrophages where fibers trap debris, cells and bacteria picked up by the lymph
3 types of tonsils:
one pharyngeal (adenoids), two palatine, and numerous lingual tonsils
germinal centers
the site in the lymph node responsible for cloning lymphocytes
two lines of nonspecific defense:
- External barriers- skin, mucous membranes
2. inflammation, antimicrobial proteins, fever, and other active attacks
Inflammation: process-
- increased blood flow due to dilation of vessels (redness and heat), increased permeability (swelling and pain), increased cell division and healing.
- WBCs stick to the walls of the dilated vessels in the inflamed area (margination)
- WBCs crawl through the vessel walls (diapedesis)
- WBCs move to where the concentration of chemicals from damaged tissues is the greatest (chemotaxis)
- WBCs phagocytize foreign material, debris, and pathogens along the way (phagocytosis)
Fever-
initiated by the production of pyrogens from activated macrophages; travel to the hypothalamus which then raises the set point for body temp; one new set point is reached (a stage called stadium), the liver and spleen hoard zinc and iron needed for bacteria growth; once defeated hypothalamus resents temp to normal
specific immunity
require prior exposure;
antigen-presenting cells
APCs;
process of presenting:
1. phagocytosis of antigen
2.lysosome fuses with vesicle containing the antigen
3. enzymes from lysosome and the antigen mix
4. enzymes break down the antigen
5. antigen residue is exocytosed
6. antigen fragment (epitope) is displayed on an MHC protein
MHC protein
Major histocompatibility complex; like a billboard posting what the APC has sampled
humoral (antibody-mediated) immunity
involves B cells making antibodies to attack foreign antigen;
process:
1. antigen presentation and T helper cell recognition
2. Cloning and differentiation
3. Antibody production for the attack
Active Immunity: Passive
indicates that the immunity was acquired through someone or something else (like a horse or a pig)
Active Immunity: Active
indicates that the body actively created its own immunity
Active Immunity: Natural
indicates the immunity was accomplished through naturally occurring means
Active Immunity: Artificial
indicates the immunity was NOT acquired through naturally occurring means
neutrophils
fight bacteria
basophils
release histamine to promote inflammation
eosinophils
attack worm parasites
monocytes
become macrophages to phagocytize bacteria
Cellular (Cell-mediated) Immunity
specific immunity; Process: 1. Antigen recognition 2. Co stimulation 3. cloning and differentiation 4. Lethal hit or interleukin secretion for other outcomes
lymphadenopathy
swollen glands
lymph
clear fluid that is made up of water, WBCs, proteins, and fats that have filtered out of blood vessels into the spaces between cells
lymphadenitis
used when swollen lymph nodes are painful or have signs of inflammation
Causes of swollen lymph nodes:
Most common:
Upper respiratory infections, infections in tissues near the swollen lymph node, dental infection
Most Dangerous:
Cancer, HIV, tuberculosis
Warning signs of swollen lymph nodes:
node is more than an inch in diameter, node that is draining pus, node that feels hard, risk factors for HIV or tuberculosis, fever, unexplained weight loss
cancers that cause swollen lymph nodes:
leukemias (typically chronic and sometimes acute lymphocytic leukemia), lymphomas, metastatic cancers (often of the head and neck, thyroid, breast, or lung)
connective tissue disorders that cause swollen lymph nodes:
systemic lupus erythematosus, sarcoidosis, Kawasaki disease
