Group 7 - Lymphatic System Flashcards
complex network of cells, tissues, and organs that work together to defend the body against harmful pathogens like bacteria, viruses, and parasites
immune system
system of vessels that carries lymph, a fluid that contains proteins, white blood cells, and other materials, throughout the body
lymphatic system
immune system and lymphatic system work hand in hand to protect the body from what?
illness and infection
main functions of the lymphatic system
- fluid balance
- lipid absorption
- defense
- by filtering and distributing lymph fluid throughout the body
- helps to eliminate waste products, toxins, and excess fluid from the tissues
- ~30L of fluid pass from the blood capillaries into the interstitial fluid each day
- only 27L pass from interstitial fluid back to capillaries
fluid balance
pass from the blood capillaries into the interstitial fluid each day
~30L of fluid
pass from the interstitial fluid back into the capillaries
27 L
- Absorbs lipids and other substances from the digestive tract through lymphatic vessels called lacteals located in the lining ofthe small intestine.
- Lipids enter the lacteals and pass through the lymphatic vessels to the venous circulation.
- The lymph passing through these lymphatic vessels, called chyle, appears white because of its lipid content.
lipid absorption
lymphatic vessels that absorbs lipids and other substances from the digestive tract
lacteals
lipid that entered the lacteals and pass through the lymphatic vessels
chyle
- Microorganisms and other foreign substances are filtered from lymph by lymph nodes and from blood by the spleen.
- Lymphocytes and other cells are capable of destroying microorganisms and other foreign substances.
- Fights infections, and filters blood and lymph to remove microorganisms.
defense
- Tiny, close – ended vessels consist of simple squamous epithelium, more permeable to blood vessels, fluid moves easily into them
- Present in most of the body tissues except CNS, bone marrow, tissues lacking blood vessels (such as epidermis and cartilage)
lymphatic capillaries
- have thinner walls than veins (same tunicas asveins)
- Contain in many valves, giving them a beaded appearance
- Lymph nodes present at certain intervals
- Small openings between endothelial cells allow for high permeability to large substances
lymphatic vessels
have a beaded appearance because they have one – way valves
small lymphatic vessels
have valves to prevent backflow of fluid
large lymphatic vessels
- characterized by housing lymphocytes and other defense cells
- found within lymphatic organs
lymphatic tissue
- originate in the red bone marrow and is carried by blood to the lymphatic organs
- divide and increase in number when expose to pathogens (part ofimmune response)
lymphocytes
lymphoid organs
- lymph nodes
- tonsils
- spleen
- thymus gland
- red bone marrow
- appendix
- rounded structures varying from small seed to almond
- Distributed vessels
lymph nodes
three superficial aggregation lymph nodes
- cervical lymph nodes
- axillary nodes
- inguinal nodes
parts of the lymph nodes
- capsule
- trabeculae
- lymphatic nodules
- lymphatic sinuses
- germinal centers
dense connective tissue surrounding each lymph node
Capsule
extension of the capsule, subdivide lymph node into compartments containing lymphatic tissue
Trabeculae
aggregation ofother cells (besides lymphocytes)
Lymphatic nodules
spaces between the lymphatic tissue that contain macrophages on a network of fibers
Lymphatic sinuses
contains rapidly dividing lymphocytes
Germinal Centers
- Patches of lymphatic tissue located around the pharynx
- First to encounter pathogens that enter via the nose and mouth
tonsils
Three groups of tonsils
- paired palatine tonsils
- pharyngeal tonsils
- lingual tonsils
Located on each side of the posterior opening of the oral cavity these ones are referred to as “thetonsils”
Palatine Tonsils
Located near the internal opening of the nasal cavity
pharyngeal tonsils
enlarged pharyngeal tonsils (this can interfere with normal breathing)
Adenoid
Made up of small bumps on the posterior surface of the tongue’sbase
lingual tonsils
surgical procedure that involves the removal of palatine tonsils
tonsillectomy
surgical procedure to remove adenoids the (pharyngeal tonsils)
adenoidectomy
- Roughly the size of a clenched fist and islocated in the left superior corner of the abdominal cavity
- Cleanses blood
- Found in all vertebrates
- Mechanical filtration of red blood cells toremove old red blood cells
- Active immune response through humoral and cell-mediated pathways
spleen
parts of the spleen
- trabeculae
- white pulp
- red pulp
from the capsule, divide the spleen into small, interconnected compartments containing two specialized types of lymphatic tissue
Trabeculae
lymphatic tissue surrounding the arteries within the spleen
White Pulp
associated with veins, consists of a fibrous network, filled with macrophages and blood cells
Red Pulp
a surgical procedure in which the spleen is removed from the body
Splenectomy
- bilobed gland roughly triangular in shape
- Located along trachea behind the sternum in upper thoracic cavity
- Produces thymic hormones
Thymus
from the capsule, divide each lobe into lobules
Trabeculae
what matures in the thymus
T cells
Dark staining area (lymphocytes are numerous)
cortex
lighter staining, central portion of the lobules (lymphocytes are few)
medulla
- Blind-ended tube connecting to the caecum
- Regarded as a vestigial organ with no known function in humans
- Rich in immune cells, including lymphocytes and plasma cells
- Located near the junction of the small and large intestines
- Shrunken remnant of the part of the caecum
appendix
diseases of the lymphatic system
- lymphadenitis
- lymphangitis
- lymphadema
- mononucleosis
- kawasaki disease
- Inflammation of one or more lymph nodes in the body
- Typically caused by an infection, such as a bacterial or viral infection, that has spread to the lymph nodes
lymphadenitis
- Swelling of lymph vessels due to inflammation
- Caused by strep infections following trauma
- Characterized by red streak at bacterial entry toarea of lymph node
lymphangitis
- A chronic condition characterized by abnormal collection of lymph fluid in extremities
- Possible caused by surgery, radiation treatments, pregnancy, burns, or trauma
lymphedema
- viral infection caused by the Epstein-Barr virus
- Somewhat contagious
- Often referred to as the “kissing disease”
mononucleosis
- Also known as syndrome”“mucocutaneous lymph node
- Acute febrile disease that is found mostly inchildren
kawasaki disease
