Lymphatic and Immune System Lab Part 1 Flashcards
what other system does the lymphatic system work parallel with?
cardiovascular system
What is a nickname for the lymphatic vessels?
cleanup crew
What are characteristics of the lymphatic vessels?
thin walled, low pressure
what do lymphatic vessels do?
return excess tissue fluid to venous circulation
What else can be present in excess tissue fluid?
damaged cells, bits of tissue and microbes
what makes up lymph?
tissue fluid, cells, and microorganisms
What does lymph bass through when returning to the venous system?
numerous small filters called lymph nodes
What are the major operational sites of the immune system?
lymphatic vessels, lymph nodes, and other lymphatic tissue
What do the major operational sites of the immune system do?
attack and destroy microorganisms and even cancer cells
what is the immune system?
collection of cells that specifically target foreign cells to prevent the spread of infections and even cancers, but it does not have its own organs
What part of the immune system makes use of other organ systems?
cells of the immune system, primarily lymphocytes
what environments does the immune system combat?
internal and external
What does the lymphatic system work with the cardiovascular system to do?
maintain fluid homeostasis in the extracellular fluid, gastrointestinal system to absorb fats
Lymphatic systems 3 primary functions
Transporting excess interstitial fluid back to the heart, absorbing dietary fats, activating the immune system
what is the process of filtration?
pushes water out of blood into the interstitial fluid
Approximately how much fluid is lost in filtration?
1.5 mL/min
What does the lymphatic system do to the lost fluid?
It picks up the lost fluid, carries it through the lymphatic vessels, and returns it to the cardiovascular system
Where does the water from interstitial fluid first go?
It enters small, blind ended lymph capillaries that surround blood capillary beds
What allows the lymph capillaries to allow substances to enter and exit?
highly permeable walls that allow large volumes of fluid to enter and exit
when is fluid called lymph?
when the fluid is inside the lymph capillaries
Where is lymph delivered to?
large lymph collecting vessels which contain valves that ensure that lymph flows in a singular direction
What do lymph collecting vessels drain into?
lymph trunks
What are the nine main lymph trunks (some split)?
jugular trunks, subclavian trunks, bronchomediastinal trunks, intestinal trunk, lumbar trunk
What does the jugular trunks drain?
head and neck
what does the subclavian trunks drain?
upper limbs
What do the bronchomediastinal trunks drain?
thorax
what does the intestinal trunk drain?
abdomen
What do the lumbar trunks drain?
pelvis and lower limbs
What do the lymph trunks drain into?
lymph ducts
What are the two lymph ducts?
right lymphatic duct and thoracic duct
What does the right lymph duct drain?
right upper limb, right side of the head, neck and thorax
What does the thoracic duct drain?
remainder of the body
Where does the right lymphatic duct deliver lymph to?
the blood at the junction of the right subclavian and internal jugular veins
Where does the thoracic duct deliver lymph to?
the blood at the junction of the left subclavian and internal jugular veins
Why are fats not directly absorbed from the small intestine directly into blood capillaries?
they are too large to enter the small vessels
where are fats absorbed?
lymphatic capillary called the lacteal
Where does the lacteal deliver fats to?
delivers the fats to lymph-collecting vessels and intestinal trunks
Where does fatty lymph go?
enters a large lymphatic vessel called the cisterna chyl
Where does the cisterna chyli drain?
thoracic duct
What do lymphatic organs activate?
the immune system
What does the immune system protect us from?
cellular injury such as trauma or pathogens
what are pathogens?
disease causing organisms, cells or chemicals
how many lobes does the thymus have?
two
where is the thymus located?
anterior mediastinum
What does the thymus secrete?
thymosin and thymopoietin
What do thymosin and thymopoietin do?
stimulate maturation of T lympocytes
When is the thymus the largest and most active?
infants and young children
What happens to the thymus in adults?
atrophies and becomes filled with adipose and other connective tissue
what are lymph nodes?
arrangements of lymphatic tissue surrounded by a connective capsule
What are lymph nodes also called?
lymph glands
Are lymph nodes glands?
No, they do not secrete any products
What do lymph nodes do?
act as filters that remove potential pathogens from lymph before it is delivered to the blood
Where are lymph nodes found?
along lymphatic vessels
What type of vessels delivers lymph?
afferent lymphatic vessels
What type of vessels drain lymph?
efferent lymphatic vessels
Where are clusters of lymph nodes found?
cervical, axillary, inguinal, mesenteric
What happens in the lymph node cortex?
immune system cells (lymphocytes, specifically B lymphocytes) and macrophages are arranged into clusters called lymphoid follicles
What seperates lymph node follicles?
inward extensions of lymph mode capsule called the trabeculae
What do germinal centers contain?
dendritic cells, macrophages, and large number of B lymphocytes
Where is the spleen located?
upper left quadrant of the abdominopelvic cavity
What does the spleen do?
filters blood and houses phagocytes
What are the two distinct regions of the spleen?
white pulp and red pulp
What does red pulp contain and what does it surround and do?
macrophages surrounding trabecular veins that destroy old or damaged erythrocytes
What does white pulp contain and what does it surround?
T lymphocytes, B lymphocytes, macrophages, dendritic cells that surrounds branches of splenic artery called central arteries
Where does the blood flow from the central arteries?
through the central arteries, and a series of arterioles until it gets to the sinusoids
What are sinusoids?
very leaky capillaries in the spleen
How does blood get to the white pulp?
pathogens leak from blood into the white pulp, they encounter immune cells that attempt to remove them from the blood
What are mucosa associated lymphoid tissues and tonsils?
clusters of loosely organized lymphatic tissue are scattered throughout mucous membranes in locations such as the gastrointestinal tract
Another name for mucosa associated lymphatic tissue?
MALT
What can MALT lack?
connective tissue capsule
What can specialized MALT be?
partially encapsulated
What is an example of specialized MALT?
tonsils
Where are the tonsils located?
posterior oropharynx and nasopharynx
Another name for pharyngeal tonsils?
adenoids
Where is the pharyngeal tonsil located?
posterior nasopharynx
Where are the palentine tonsils located?
posterior oropharynx
Where are the lingual tonsils located?
base of tongue
What tonsils may or may not be present in everyone?
tubal tonsils
What is another example of MALT?
peyers patches
What are peyers patches?
clusters of MALT located in the terminal portion of the small intestine (ileum)
Characteristics of Peyers patches
somewhat resemble lymph nodes, less defined germinal centers and lymphoid follices, capsules are incomplete or absent
