lymphatic system

what does the lymphatic system do?

transports, filters and cleans body fluids of pathogens, toxins and other unwanted substances

what does the extracellular body fluids include?

plasma in the bloodstream, interstitial fluid in tissues, lymph in lymphatic vessels and nodes

microscopic _________ _________ are very permeable

lymphatic capillaries

what does microscopic lymphatic capillaries feed into?

larger and larger lymphatic vessels and ducts

what are 3 functions of the microscopic lymphatic capillaries?

pick up excess interstitial fluid, route it through lymph nodes for filtering, and return it to the blood stream

what is the pathway of the lymph?

lymph always moves toward the heart and is eventually returned to the venous system through ducts

what does the right lymphatic duct do?

drains lymph from the upper, right side of the body

_________ ____ receives lymph from the rest of the body

thoracic duct

how does lymph move through the body?

contraction of skeletal muscles, pressure changes in the thoracic cavity, smooth muscle contractions in vessel walls

what is the function of the lymph nodes?

filter unwanted substances such as pathogens and cancer cells from the lymph

where is the primary site of lymphocyte production during an immune response

lymph nodes

what type of fiber acts as a net to catch debris?

reticular fibers

_________ live on the fibers

macrophages

_________ live within the spaces of reticular fibers

lymphocytes

what are the two types of white blood cells in lymph nodes

macrophages and lymphocytes

where do macrophages develop?

monocytes

what do macrophages do?

engulf and destroy bacteria and other foreign substances

what are two functions of lymphocytes?

monitor fluid for presence of antigens and can trigger an immune response

how do you know when an infection is present?

lymph nodes may swell and become tender

how are swollen lymph nodes caused?

by large numbers of trapped bacteria or viruses

how does metastasis occur?

cancer spreads to a new location in the body away from its original site

why does metastasis often happen through the lymphatic system?

the extreme permeability of lymphatic vessels

what is the function of the tonsils?

trap pathogens entering the throat

what is the function of the thymus?

involved in producing lymphocytes in children

what is the function of Peyer’s Patches?

capture and destroy bacteria in the small intestine

what is the function of the spleen?

filters pathogens and debris from blood

(1)

right lymphatic duct

(2)

thymus gland

(3)

axillary lymph node

(4)

peyer’s patches

(5)

appendix

(6)

red bone marrow

(7)

tonsils

(8)

cervical lymph node

(9)

entrance of thoracic duct subclavian vein

(10)

spleen

(11)

thoracic duct

(12)

cisterna chyli

(13)

lumbar lymph node

(14)

inguinal lymph node

(15)

pelvic lymph node

(1)

arteriole

(2)

endothelial cells

(3)

blood vessel capillaries

(4)

closed valves prevent backflow

(5)

venule

(6)

lymph flows through open valves

(7)

interstitial fluid

(8)

tissue cells

(9)

lymphatic capillaries