Exam Two Flashcards
What are the three main parts to the lymphatic system?
Lymphatic vessels
Lymph
Lymph nodes
How does the lymphatic system help maintain homeostasis?
Returns fluid that has leaked from the blood vascular system back to the blood
Filtration
Immune system activation
What is the function of lymphatic vessels?
Forms a one way system that takes fluid that has leaked from capillaries back to venous system
What is lymph movement dependent on?
Skeletal muscle contraction
What is lymph?
Fluid in lymphatic vessels
Consists of water, electrolytes, proteins and waste
What is the specialized lymph that picks up fat?
Lactile
Found in the intestinal mucosa
What is the one location where lymph is thicker?
Intestines
What is the main function of lymph nodes?
Filters lymph
Activates the immune system
How does lymph go through lymph nodes?
Lymph enters through many afferent lymphatic vessels
Can only leave through two efferent vessels
What is the reasoning for having more afferent vessels than efferent vessels?
Causes the flow to be slow so filtration can occur
What are the main immunocompetent cells?
B cells
T cells
What is the function of B cells?
Produce plasma cells that produce antibodeis
What is the function of T cells?
Directly attack infected cells
Where do B cells mature?
Red bone marrow
Where do T cells mature?
Thymus gland
What is the function of the spleen?
Filters the blood
What are the two regions of the spleen?
Red pulp - where filtration occurs
White pulp - contains lymphocytes
What are the secondary lymphoid organs?
Spleen Thymus Tonsils MALT Peyer's Patches Appendix
What are the four types of tonsils?
Palantine
lingual
Pharyngeal
Tubal
Where are palantine tonsils located?
Back of the throat
Where are lingual tonsils located?
Base of the tongue
Where are pharyngeal tonsils located?
Posterior wall of nasopharynx
Often called adnoids
Where are tubal tonsils located?
Opening of the auditory tube
What is the function of tonsils?
Binds to and kills bacteria
Where are peyer’s patches located?
Throughout the distal wall of the small intestine
What is the function of peyer’s patches?
Attempts to kill bacteria before it breaches the intestine wall
What is MALT?
Mucosa Associated Lymphatic Tissue
Protects openings to the outside world
What is lymphoid tissue largely composed of?
Reticular connective tissue
What are medullary cords?
Thin inward extensions from the cortical lymphoid tissue
What are lymph sinuses?
Large lymph capillaries spanned by crisscrossing reticular fibers
What is the order of structures that lymph goes through in lymph nodes?
Afferent lymphatic vessels Subcapsular sinus Medullary sinuses Efferent lymphatic vessels Hilum
What are the two lymphatic ducts?
Right lymphatic duct
Thoracic duct
What is the function of the appendix?
Destroy pathogens before they can breach the intestinal wall
Generate many memory lymphocytes for long term immunity