Lymphatic System (capillaries, vessels, and organs) Flashcards
What are the three main functions of the lymphatic system?
- Maintains fluid balance in tissues
- Absorbs lipids from small intestine/digestive tract
- Defends the body against microorganisms and other foreign substance
Lymphatic vessels carry _____ away from ______.
lymph; tissues
Lymphatic capillaries lack a _____ and have loosely _______ ______ cells.
basement membrane; overlapping epithelial
Lymphatic capillaries join to form __________.
lymphatic vessels
Lymphatic vessels have _______ that ensure a _______ flow of
_________.
valves; one-way; lymph
What causes the lymph to move?
- Contraction of lymphatic vessel smooth muscle
- Contraction of skeletal muscle
- Thoracic pressure changes
Lymph moves through vessels by the ________ of the skeletal muscles and pressure changes created by respiration
“milking action”
Lymphatic capillaries are ________ tubes in which adjacent _______ cells _____ each other, forming _________.
blind-ended; endothelial; overlap; flaplike minivalves
Lymph nodes are found along the ________.
lymphatic vessel
After passing through the lymph nodes, the lymphatic vessels
converge to form larger vessels called ___________.
lymphatic trunks
drains lymph from a major portion of the body
lymphatic trunk
The lymphatic trunks either connect to large veins in the thorax or join to yet larger vessels called
lymphatic duct
The two lymphatic ducts
right lymphatic duct & thoracic duct
The largest lymphatic vessel is the ________.
thoracic duct
drains lymph from the right side of the body inferior to the thorax and the entire left side of the body
thoracic duct
drains lymph from the upper right quadrant of the body
right lymphatic duct
the lymphatic trunks form a sac called the _______, a sac that joins the inferior end of the thoracic duct
cisterna chyli
Lymphatic trunks and ducts empty into the blood at ________.
thoracic veins
Lymphatic tissue is ________ tissue that contains lymphocytes and other cells.
reticular connective
Areas where lymphatic tissue are concentrated
lymphatic/lymphoid organs
What are the Lymphatic tissues that are surrounded by a capsule?
lymph nodes, spleen, thymus
What are the nonencapsulated Lymphatic tissues?
diffuse lymphatic tissue, lymphatic nodules, tonsils, Mucosa-associated lymphoid tissue (MALT)
is nonencapsulated lymphatic tissue located in and below the mucous
membranes of the digestive, respiratory, urinary, and reproductive tracts
Mucosa-associated lymphoid tissue (MALT)
consists of dispersed lymphocytes, macrophages, and other cells, and has no clear boundaries blends with surrounding tissues
Diffuse lymphatic tissue
where immune cells (lymphocytes and macrophages) are PRODUCED and
MATURE to the point where they can produce a normal immune response
(immunocompetent)
Primary lymphoid organs
What are the 2 primary lymphoid organs?
Red Bone Marrow
Thymus Gland
are the sites where the MATURE lymphocytes RESIDE and carry
out immune response
Secondary lymphoid organs
denser arrangements of lymphatic tissue organized into compact, somewhat spherical structures
Lymphatic nodules
aggregations of lymphatic nodules in the distal half of the small intestine and the appendix.
Peyer’s patches
lymphatic nodules found within lymph nodes and the spleen
lymphatic follicles
where lymphocytes (both T-cell and B-cells) arise
Red bone marrow
Site of maturation in T-cells; decreases in size after puberty
Thymus gland
lymphatic tissue surrounding the ARTERIES within the SPLEEN; contains a great number of lymphocytes; 1/4 of the spleen’s volume
white pulp
associated with the VEINS within the SPLEEN; consists of a fibrous network, filled with macrophages and red blood cells, and enlarged capillaries that connect to the veins; 3/4 of the spleen’s volume
red pulp
Foreign substances in the blood passing through the spleen can stimulate an __________ because of the presence of _______ in the __________.
immune response; lymphocytes; white pulp
Foreign substances and defective red blood cells are removed from
the blood by ________ in the _________ of the spleen.
phagocytes; red pulp
Located in the left superior corner of the abdominal cavity; has an outer capsule of dense connective tissue and a small amount of smooth muscle
spleen
The spleen filters ________ instead of lymph.
blood
The spleen’s functions are:
- destroying defective red blood cells
- detecting and responding to foreign substances in the blood
- acting as a blood reservoir
The ________ of the spleen are a limited reservoir for blood.
splenic cords
bilobed gland in the superior mediastinum and is divided into a cortex and a medulla
Thymus
A hormone secreted by the thymus that is important in the
T-cell maturation process.
Thymosin
what are the secondary lymphoid organs?
Spleen, Lymph Nodes, MALT (Tonsils, Peyer’s Patches, and Appendix)
are small, round or bean-shaped structures distributed along the course
of the lymphatic vessels that filters lymph and removes bacteria and other materials.
Lymph nodes
lymphocytes ________, _________, and _________ within lymph nodes.
congregate; function; proliferate
Lymph nodes are categorized as __________ or ________.
superficial; deep
__________ carry lymph to the lymph nodes, where it is filtered, and __________ carry lymph away from the lymph nodes
Afferent lymphatic vessels; efferent lymphatic vessels
large groups of lymphatic nodules in the pharynx that protect against bacteria entering through the nasal or oral cavity; decrease in size after puberty and eventually may disappear
Tonsils
The three groups of tonsils
- Pharyngeal tonsils
- Palatine tonsils
- Lingual tonsil
When the pharyngeal tonsil is enlarged, it is commonly called the ________.
adenoid
large, oval, lymphatic masses on each side of the junction between the oral cavity and the pharynx; What most of us think of as our “tonsils” are
palatine tonsils
aggregated lymphoid nodules; large clusters of lymphoid follicles, structurally similar to the tonsils; located in the wall of the distal portion of the small intestine
Peyer’s patches
Function of Peyer’s patches
monitor intestinal bacteria populations and prevent the growth of pathogenic bacteria in the intestines
is a tubular offshoot of the first part of the large intestine and contains a high concentration of lymphoid follicles
Appendix
