Lymphatic System Flashcards
Functions of the lymphatic system
- Transport dietary lipids (absorbing product of fat digestion in small intestine)
- immune response (against pathogens)
- Regulate interstitial fluid volume (returning to blood)
-filter lymph before returning to blood
Pathogen
Microscopic organism that causes disease
Viruses, parasites, fungi, bacteria
Proliferation
When immune cells are stimulated to divide
Immunity
Ability to fight infection/disease
Susceptibility
Vulnerability or lack of resistance to disease
Antigen
Substance able to provoke an immune response
Protect the mucous membranes and don’t have a capsule.
Two types: tonsils and Peyers Patch
MALT
Innate immunity
- Present from birth
- response genetically predetermined
- produces the same response every time
Phagocytic cells
- Engulf and destroy foreign compounds and pathogens
- 1st cellular defense
- act as antigen presenting cells
Small phagocytic cell
Microphages
Phagocytic cell forms pseudopod to engulf target
Pseudopod
Formed when pseudopods engulf target
Phagosome
Heparinized
Prevent blood clot
Agglutinogen
Genetically determined antigens on the surface of ones erythrocytes
Agglutinins
Antibodies in plasma of blood
- test presence of agglutinogens
- bind to antigens
Hematocrit
Percentage of total blood volume of comprised packed red cells.
OXYGEN CARRYING CAPACITY
Hematocrit calculation:
Red cell/total blood X 100
Normal hematocrit ranges
Male: 40-50%
Female: 36-45%
Agglutination
Antigen/antibody reaction that causes RBC to clump together
Clumping = positive or negative?
No agglutination = negative
Agglutination = positive
Leukocyte
WBC protecting the body against disease (5 types)
Agranulocytes
Lymphocytes = 25-30% Monocytes = 3-8%
*no cytoplasmic granules
Granulocytes
Neutrophils = 60-70% Eosinophils = 2-4% Basophils = 0.5-1%
*contain cytoplasmic granules
Class average {hematocrit}
Male: 62.4%
Female: 53.4%
Heme
Iron containing compound of porphyrin
Forms non protein part of hemoglobin
5 nodes
Cervical Axillary Cubical Intestinal Inguinal
Red pulp
Vascular tissue forming majority of the spleen
-venous sinus
White pulp
Lymphatic tissue (purple dots) in dark nuclei of lymphoid tissue -central arteries
Red pulp function
Store platelets
Hemopoiesis in fetal life
Macrophage remove old RBC
White pulp function
“Islands” consisting of lymphocytes and macrophages
-T and B cells perform immune responses, while macrophages phagocytize (destroy pathogens)
Lymphoid nodules
Composed of a compact mass of close and overlapping lymphoid cells
- not distinct because no capsule
- measure in mm
Peyers Patch
Located in submucosa of ileum and colon
Tonsils
Nodules in connective tissue deep to epithelia lining respiratory tract
Two primary lymphatic organs
Red bone marrow and thymus gland
- where lymphocytes form and mature
- provide stem cells to divide and mature into B and T cells
Secondary lymphatic organs
Where lymphocytes are activated: lymph nodes and spleen
-capsule, trabeculae, reticular fiber
Lymphatic nodules: MALT
Tonsils and Peyers Patch
-egg shaped mass of lymphatic tissue not surrounded by capsule because they’re scattered through lamina propia of mucous membrane
(Line GI, urinary, respiratory tract/airway)
Lysosomal enzymes
Digest targets
Broken down components leave by:
Exocytosis
Immunological surveillance
NK cells - lymphocyte
- look for abnormal cells
- release perforins
- performs create a hole in abnormal cell membrane
- causes lysis of cell and kills it
Complement activation
30+ plasma proteins made in the liver
Can begin in 3 pathways
Cytolysis
Complement proteins form membrane attack complex
Opsonization
Complement proteins coat target cell and enhance phagocytosis
-increase inflammation, typically due to mast? Cells
Interferon
Viruses that need host cell to replicate 3 types: alpha beta gamma
Alpha and beta
Inhibit viral replication
Stops virus from replication within host cell
Gamma
Produced by lymphocytes
Stimulates macrophages and neutrophils to kill bacteria
Chemotaxis
Attracts other immune cells
Inflammation
Localized tissue response to injury
Macrophages
Phagocytic cell clean up cell debris and pathogens
Attract neutrophils and monocytes
Fever
Greater than 37.7 C or 99.9 F
Pyrogens
Reset internal thermostat in hypothalamus to higher set point
Pyrogens functions
Can inhibit pathogen activity
Increases metabolic rate
Speeds up immune response
Adaptive immunity
Body identified and recognizes foreign substances
Response should be better and faster each time it encounters the same pathogen
