Lymphatic

Functions of lymphatic system?

Transport escaped fluids from cardio system back to blood... body defense/resistance to disease

What is "lymph"?

excess tissue fluid and plasma proteins carried by lymphatic vessels

What happens if fluids are not picked up?

edema (swelling)

Where do lymphatics pick up and return lymph?

lymph capillaries (between blood and tissue cells), return to venous system

Which direction do lymphatic vessels flow?

One-direction... TO HEART

How do lymph capillaries pick up lymph?

Lymph capillary walls overlap to form minivalve flaps, fluid leaks in, higher pressure inside closes the minivalves -> fluid forced toward heart

What connects lymph capillaries to local region?

filaments anchored to connective tissue

These structures collect lymph from lymph capillaries...

lymph vessels

What structures carry lymph to and from lymph nodes?

lymph vessels

What drains lymph from Rt arm, head, thorax?

Right lymphatic duct

What drains MOST of body?

Thoracic duct

What pumps lymph transport?

NOTHING. It is low pressure, pumpless system

How is lymph transported?

milking action of skeletal muscles, pressure changes due to breathing, smooth muscle in walls of lymphatics

T/F, lymphatics are lined with smooth muscle?

TRUE

Function of lymph nodes?

Filter lymph (bacteria, viruses, cancer cells, cell debris)

What kind of defense cells are produced in lymph nodes?

Macrophages and lymphocytes

function of macrophages?

engulf and destroy bacteria, viruses, etc

function of lymphocytes?

respond to foreign substances in lymph

Sections of lymph nodes?

Cortex (outer), Medulla (inner)

What is contained in lymph node cortex?

follicles - collections of lymphocytes... germinal centers - enlarge when antibodies released by plasma

What is contained in lymph node medulla?

phagocytic macrophages

Trace the flow of lymph through a node...

Enters convex side of kidney shape through afferent vessels -> through sinuses -> exits through efferent vessels

Why is flow slowed through lymph node?

Less efferent (exit) than afferent (enter) vessels

Are lymph nodes the only lymphatic structures?

No. Spleen, thymus, tonsils, Peyer's patches, Appendix

Lymphatic function of spleen?

Filters bacteria, viruses, debris from blood.. Destroys worn out blood cells... blood reservoir

What organ is a site of lymphocyte proliferations and immune surveillance?

Spleen

Function of thymus?

peak levels only during youth.... Ok nice

Function of tonsils?

trap and remove bacteria --> tonsilitis is congested with bacteria

These structures are found in the wall of small intestine, containing lymphoid follicles (similar to appendix) that contain macrophages that capture and destroy bacteria in intestine...

Peyer's patches

What are MALT's? (Mucosa associated lymphoid tissue)

sentinels that protect respiratory and digestive tracts...

Peyer's patches, Tonsils, and appendix are forms of _____

MALT's. Mucosa associated lymphoid tissues