Exam 3. Lymphatic and Immune system Flashcards
A&P II chapter 22
Functions of the lymphatic system
Fluid recovery: To maintain blood pressure
Immunity: Lymphatic cells in the lymph and nodes
Lipid absorption: Lacteals pick up that were not absorbed
Components of the lymphatic system
Lymph Lymphatic vessels Lymphatic cells Lymphatic tissues Lymphatic organs
Lymph
clear colorless similar to plasma. No formed elements
Lymphatic vessels
Transport lymph back to the blood
Lymphatic cells
B, T-lymphocyte, NK, Macrophage, dendritic cells the and reticular cells
Dendritic and Reticular cells
Function like macrophages
Can also: Sound the alarm to alert other immune cells of a foreign substance, cancer cells, diseased cells
Lymphatic tissue
Not a new tissue, a large aggregation of lymphatic cells
Lymphatic organs
Several lymphatic cells
the structure will have a capsule that separates the lymphatic cell from everything else around them.
Bone marrow, Thymus, Lymph nodes, tonsils, spleen
Lymphatic capillaries
Exchange of fluid
penetrate almost all tissue int he body
absent from CNS, cartilage, cornea and bone marrow
Blind-ended capillaries
Large gaps that allow continues to flow into it
Lymphatic vessels
Very similar to veins
Tunica Interna, media and externa
How do we move the lymph?
Skeleton muscle pump
Thoracic pump
One way valves
Lymph flow
Lymphatic capillaries Collecting vessels Six lymphatic trunks Two collecting ducts Subclavian vein
Six lymphatic trunks
Jugular- cephalic Subclavian- arms Bronchomedistinal- heart, bronchi, lungs Intercostal- ridge cage muscles Intestinal- abdominal organs Lumbar- legs
2 Collecting ducts
End of line
RIght lymphatic duct: Right jugular, R. subclavian, R, bronchomediastenal, R intercostal.
Thoracic ducts: Everything else. Sarts below the diaphragm.
the starting point called cisterna chylii
Redbone marrow function in the lymphatic system
Where the lymphatic cells are produced, NK B, T, macrophages
Thymus in the lymphatic system
T-cell maturation
by secreting thymosin and thymopoietin
Spleen
Red and White Pulp.
In red pulp: storage of erythrocytes
In white pulp: lymphatic tissue, cells. Where spleen monitors for anything foreign.
Lymph Node
It monitors the lymph
Most numerous lymphatic organs
It cleanses the lymph
acts as a site of activation for T and B cell
The dendritic cells and macrophages will be the first to encounter foreign material here.
BMT cells will be activated here
The tonsils
Protects against invaders via respiration or ingesting food
1st line of defense against pathogens
External barriers
Skin, mucous membranes
Dermis, epidermis (stratifies squamous epithelium)
Sweating making it more acidic
2nd line of defense against pathogens
- Innate, non-specific, built in mechanisms
- Leukocytes, antimicrobial proteins, immune surveillence (NK cells) inflammation and fever
3rd line of defense against pathogens
- The immune system, most sophisticated
- Adaptive or specific immune response, meaning it can adapt to specific pathogens the boy is fighting.
- Once the pathogen is defeated, a memory will be produced so the body can respond it faster the second time.
Phagocytes
Phagocytic cells that phagocytize foreign matter
Five types of leukocytes
Neutrophils Eosinophils Basophils Monocytes Lymphocyte
Neutrophils
- 3-5 lobes
- most abundant
- defend against bacteria infection bu phagocytizing the bacteria, building NETS (neutrophil, extracellular traps) and they produce a cloud of chemicals through respiration burst
Respiration burst
Neutrophils dump their oxidizing chemicals into the environment.
They deploy their NETs to trap bacteria nearby
Since they use their own chromosomes to make the NETs the neutrophil will also die
Eosinophils
2 lobe, red granules
- Defend against parasitic infection
- Migrate to the area to bombard the parasite with enzymes
- Regulate cells that promote the inflammatory response
- Phagocytise antigen-antibody complex
- Promote basophils during allergic reactions
Basophils
Rare, dark and grany
- Initiates inflammatory response (leukotrienes, histamine, and heparin)
Leukotrienes
Signal chemical by basophils.
It attracts leukocytes to the area, neutrophils, and eosinophils
Histamine
Vasodilator
this speeds leukocytes tot he area of injury
Heparin
Prevent coagulation,
prevents the formation of clots to allow leukocytes to get to the area
Mast cells
Also, secrete same substances as basophils
they come from connective tissue
Monocytes
Large, kidney bean
- can leave blood vessel and go into the tissue
- Once they leave blood vessel they become macrophages
- Macrophages are cells that will phagocytize anything that is foreign, dead, damaged or diseased
Wandering macrophages
Macrophages that move from blood to tissue, to back into the blood
Fixed macrophages
Macrophages that cant leave an area or organ
Microglia: CNS
Alveolar: Lungs
Hepatic: Liver
Antimicrobial Proteins
Proteins that inhibit microbial reproduction and provide short term, non-specific resistance to pathogenic bacteria and viruses.
The two families of antimicrobial proteins
Interferons
Complement system
Interferons
Work against viral infection when they infect a lymphocyte.
Lymphocyte realizes they are infected and are dying
The lymphocyte will secrete interferons to alert cells of what is coming.
This prevents the virus from binding to other cells
Complement system
Part of antimicrobial proteins
It consists of about 30 proteins that complement the specific immunity and non-specific resistance
-It is activated by 3 different pathways
- Once it is activated it can start 4 methods of destructions
3 pathways, once they are activated they end up at complement protein C3. They become activated C3a or C3b. After, those go on to activate the 4 methods of destruction
3 pathways of the complement system
- Classical
- Alternative
- Lectin