Midterm 3 parades Flashcards
What are the pressures that influence capillary exchange?
Hydrostatic pressure and osmotic pressure
Explain Hydrostatic pressure
Pushes fluid across the boundary
Explain Osmotic pressure
Pulls fluid thru the boundary
what influences the vasomotor tone of our blood vessels
sympathetic nervous system which innervates the smooth muscles to cause vasodilation and vasoconstricton
what is the function of the lymph node
filter lymph and activate immune response
when are lymph nodes most active
where there is an infection
What is the function of the spleen
stores breakdown products of RBCs for later re-use, stores blood platelets, site of fetal erythrocyte production (normally ceases after birth)
when is the spleen most active
where there is any injury or disease that affects the blood supply
What is the function of the tonsil
gather and remove many of the pathogens entering the pharynx in food or inhaled air
When is the tonsil most active
during childhood (ages 4-10)
what is the function of the Thymus (lymph system)
trains T cells (does not directly fight antigens)
when is the thymus most active
during childhood (neo-natal and pre-adolescent periods)
what is the principal lymphoid organ
lymph node
how does lymph flow through a lymph node
flows into the node thru afferent lymphatic vessels and filters thru to exit thru the efferent lymphatic vessels
Why are there fewer efferent than afferent vessels in the lymph node
to slow the flow to allow time for filtration
What is the simplest lymphoid organ
the tonsils
What is the distribution of the lymphatic vessels
right lymphatic duct and thoracic duct
What body parts does the thoracic duct drain
all of body EXCEPT right upper arm, right side of head and thorax
What body parts does the Right Lymphatic duct drain
Right upper arm and the right side of head and thorax
what is a lacteal
special lymphatic capillaries of small intestines that take up lipids
What is Peyer’s Patches
Clusters of lymphoid follicles found in the wall of the distal portion of the small intestine
what is the function of Peyer’s patches
- destroy bacteria, preventing them from breaching the intestinal wall;
- Generate “memory” lymphocytes (for long term immunity)
Which cells mature in the Hassall’s corpusles (found in thymus)
Regulatory T cells (prevents autoimmune responses)
What is the difference between innate and adaptive immune systems?
Innate Immune system is
Non-specific
Has 2 lines of defense (skin and mucosa; cells, chemicals
adaptive immune system is specific
specific (this is 3rd line of defense)
attacks a particular foreign substance
takes longer to react than the innate