Questions and Notes - Chapter 20
Both types of lymphocytes are found in the medullary cords, which are
inward extensions of cortical lymphoid tissue in lymph nodes.
Twenty years ago, it was common practice to remove the spleen if it was damaged. This is now contraindicated, because
it has been shown that the spleen can heal itself
What lymphatic structure absorbs lipids in the intestine?
lacteal
Fats absorbed from the small intestine are transported to the bloodstream via ________
lacteals
Liquefied fat, called chyle, is carried by
lacteals from the small intestine to the blood stream.
lymph enters blood circulation through where?
left subclavian vein
Where would you expect buboes to develop?
likely near or at the site of an infection
What is protein-containing fluid within the lymphatic vessels?
lymph
A sentinel node is the first lymph node that receives
lymph drainage from a body area suspected of cancer
Small secondary lymphoid organs, which cluster along lymphatic vessels, are termed
lymph nodes
What is the pathway of lymph (from where to where)?
lymphatic capillaries to lymphatic vessels to lymphatic trunks to lymphatic ducts
lymph nodes filters debris and foreign matter from the
lymphatic fluid
Vessels that collect excess tissue fluid and return it to the blood stream are called
lymphatics
The spleen's white pulp is composed primarily of _________
lymphocytes
What is the unique structural modification in lymphatic capillaries that increases their permeability?
minivalves
What lymphatic structures trap bacteria in the posterior oral cavity?
palatine tonsils
What tonsils are most often infected?
palatine tonsils
Which tonsil is located in the posterior wall of the nasopharynx and is referred to as the adenoids if it is enlarged?
pharyngeal tonsil
Antibodies that act against a particular foreign substance are released by ________
plasma cells
Which lymphoid cells produce antibodies?
plasma cells
Spleen contains specific tissues called the
red and white pulp
Lymphangitis presents itself as __________.
red lines under the skin that are sensitive to touch
Which region of the spleen has splenic cords and splenic sinusoids
red pulp also the site of red blood cell destruction
What is typically found within the sinuses of a lymph node?
reticular fibers
lymph nodes contain macrophages suspended on a network of
reticular fibers
B cells produce plasma cells, which do what?
secrete antibodies into the blood.
The unresponsiveness of our lymphcytes to our own body cells is called
self tolerance
lymph nodes contains fluid-filled spaces called the
sinuses
In addition to its lymphoid function, which organ holds a reservoir of platelets?
spleen
What lymphatic structure may also be a site of erythrocyte production in the fetus?
spleen
Right lymphatic duct drains all lymph collected from the upper right area of the torso, as well as the right arm and right side of the head and thorax and feeds it into what?
the Internal Jugular Vein
Spleen filters debris and foreign matter from
the blood
The trabeculae of lymph nodes extend deeply from the what and do what
the capsule divide the node into multiple compartments.
Where are the three large clusters of superficial lymph nodes?
the cervical (neck), inguinal, and axillary (armpit) regions
the thoracic duct drains the lymph from
the entire left side of the body and the right abdomen and leg.
What are the 3 types of tonsils
the pharyngeal tonsil the palatine tonsils the lingual tonsils
Spleen is served by fluid-containing vessels at the helium called
the splenic artery
The Tonsillar crypts allow better immune function, but
they are prone to infection
Which of the following is false in regard to natural killer cells - they are specialized lymphocytes - they react against very specific pathogens
they react against very specific pathogens
Medullary cords are what
thin, inward extensions from the cortical lymph tissue in the lymph node.
Although B and T lymphocytes originate in the bone marrow, T cells mature in the ________
thymus
EXCEPT for the __________, which is/are an endodermal (inner layer in the embryo) derivative, the lymphoid organs develop from mesodermal (middle layer in the embryo) mesenchymal cells.
thymus
Which region of the spleen is composed mostly of lymphocytes
white pulp; it is the region composed mostly of lymphocytes.
Where do B cells mature?
B cells mature in the bone marrow.
The first antibody class to. be released into bloodstream during a primary immune response is
IgM
What is lymph? Where does it come from?
Lymph is the fluid inside lymphatic vessels. It enters lymphatic vessels from interstitial fluid. Interstitial fluid, in turn, is a filtrate of blood plasma.
What is the driving force for lymph movement?
Lymph movement is driven by the contraction of adjacent skeletal muscles, pressure changes in the thorax during breathing, the pulsations of nearby arteries, and contraction of smooth muscle in the lymphatic vessel walls. (Valves in lymphatic vessels prevent backflow of lymph.)
What small organs are intimately associated with lymphatic vessels?
Lymph nodes
What distinguishes lymphatic vessels from veins?
Lymphatics can collect and carry large materials, even some cellular debris, that cannot penetrate the walls of veins
What is the largest lymphatic organ?
Spleen
What lymphoid organ is not apart of MALT?
Spleen
What stores blood platelets?
Spleen
What are the 4 important lymphoid organs?
Spleen thymus tonsils adenoids
Where do T cells mature?
T cells mature in the thymus.
Larger Thoracic duct takes lymph from the lower and left side of the body and feeds it into what?
The Subclavian vein
Lymphatic capillaries are NOT found in what?
bone marrow
These proteins are release by infected cells and help protect surrounding unaffected cells
interferons
What lymphatic trunks is unpaired?
intestinal trunk
List several functions of the spleen (4)
- The spleen cleanses the blood - recycles breakdown products of RBCs - stores iron, platelets and monocytes - thought to be a site of erythrocyte production in the fetus.
Tonsillar crypts are invaginations deep into the interior of the tonsil. What structure(s), found in most other lymphoid organs, is/are missing from the tonsil that allows for the presence of these crypts?
Absence of a capsule allows fluids from the throat and mouth to enter crypts and get close to lymphatic tissue.
Your patient has had her spleen removed after it was ruptured in a motorcycle accident. Which of the following is your greatest concern for her future health status?
After splenectomy, your patient has a markedly increased risk of overwhelming bacterial infection. The spleen helps fight certain kinds of bacteria that cause pneumonia and meningitis
What is a bubo?
Buboes are swollen lymph nodes that are usually tender to the touch. This is usually due to the lymph node being overwhelmed by pathogens, such as large numbers of bacteria.
Excess tissue fluid in the brain drains into the __________
CSF (Cerebrospinal fluid)
How are collecting lymphatic vessels different from veins?
Collecting lymphatic vessels have more internal valves than do veins.
Which of the following lymphoid cells trap antigens and transport them to lymph nodes?
Dendritic cells assist in the immune response by capturing antigens and delivering them to T cells in the lymph nodes.
True or False Blood plasma and lymph are identical except for their respective locations in the body.
False Lymph is more like interstitial fluid than plasma, except for lymph from the digestive organs, where it is a nutrient-rich fluid.
Which of the following is a function only of the lymph nodes and not the other lymphoid organs Filter lymph Store lymphocytes fight infection generate memory lymphocytes
Filter lymph
Cytotoxic T cells release which two molecules when they recognize their targets?
Granzymes and performs
What is the benefit of having fewer efferent (carries filtered lymph out of the node) than afferent (flow into a lymph node and carry unfiltered lymph fluid) lymphatics in lymph nodes?
Having fewer efferents causes lymph to accumulate in lymph nodes, allowing more time for its cleansing.
What is a lymphoid follicle? What type of lymphocyte predominates in follicles, especially in their germinal centers?
Lymphoid follicles are solid, spherical bodies consisting of tightly packed reticular fibers and lymphoid cells, often with a lighter-staining central region. They are regions where B cells predominate.
What lymphoid organs destroys bacteria before it can breach the intestinal wall and generates "memory" lymphocytes for long-term memory?
MALT (mucosa associated lymphatic tissue) in the intestinal wall destroy bacteria before they can breach the intestinal wall. They also generate "memory" lymphocytes for long-term memory.
What is MALT? List several components of MALT
MALT (mucosa-associated lymphoid tissue) is lymphoid tissue found in the mucosa of the digestive, respiratory, and genitourinary tracts. It includes tonsils, Peyer's patches, and the appendix.
Which cell type in the lymph node has an active role in filtering the lymph through the phagocytosis?
Macrophages
What are isolated clusters of lymph follicles found in the wall of the small intestine?
Peyer's patches
Which of the following lymphoid organs is NOT matched with its function? bone marrow: form lymphocytes spleen: remove old red blood cells Peyer's patches: site of B cell maturation thymus: site of T cell maturation
Peyer's patches: site of B cell maturation
Where do B lymphocytes mature?
Red bone marrow
Both B and T cells originate in red bone marrow. Where do you find red marrow in adults?
Red bone marrow in adults is found in the cavities between trabeculae of spongy bones in the flat bones of the skull, the sternum, ribs, clavicles, scapulae, hip bones, and vertebrae. In addition it is found in the heads of the femur and humerus.
What is the main function of the lymphatic system?
The lymphatic system returns leaked fluid and plasma proteins that escape from the bloodstream to the blood.
What are the primary lymphoid organs and what makes them special?
The primary lymphoid organs are the red bone marrow and thymus. Primary lymphoid organs are special because they are the organs where lymphocytes originate and mature.
Name two lymphatic ducts and indicate the body regions usually drained by each.
The right lymphatic duct receives lymph from the right upper arm and the right side of the head and thorax. The thoracic duct drains lymph from the rest of the body.
Which lymphoid organ extracts aged and defective blood cells and platelets from the blood in addition to storing some of the breakdown products for later reuse?
The spleen harbors macrophages that ingest and recycle materials from erythrocytes that have aged or become damaged.
From which blood vessel does the splenic artery arise?
The splenic artery arises from the celiac trunk.
The splenic vein empties into which blood vessel?
The splenic vein empties into the hepatic portal vein.
Which lymphoid organ is primarily active during the early years of life?
The thymus is responsible for the maturation of T lymphocytes, and while it is large in youth, it tends to be reduced in size as the body ages.
What lymphoid organs is part of a collection of tissues called the mucosa-associated lymphoid tissues (MALT) and removes pathogens entering the pharynx (throat)?
The tonsils function to protect the throat and surrounding tissues from infection via the mouth and nose.
What causes the pooling of lymph inside a lymph node?
There are more afferent vessels than efferent lymph vessels
What is a role of lymph nodes?
They filter lymph
lymph nodes have fewer efferent vessels than afferent vessels. why
This slows the flow of the lymph through the node
What receives lymph from most of the body
Thoracic duct
B cells are not found in what lymphatic organ?
Thymus
The lymphoid organ that does not directly fight antigens?
Thymus
What structure ensures that the T lymphocytes are immunocompetent
Thymus
These connective tissue strands divide lymph nodes into compartments
Trabeculae
Lymphatic vessels push blood back to the heart by what 3 mechanisms?
Valves smooth muscles skeletal muscles
list the correct order of lymph flow through the lymph node?
afferent vessel, subcapsular sinus, medullary sinuses, efferent vessel
Lymph follicles are what
aggregations of lymphocytes in the lymph node.
Where in the body are lymph nodes located?
along lymph vessels and clustered in the axillary, inguinal, and cervical regions
Dendritic cells have many appendages like tree branches, and collect
antigens to deliver to lymph nodes for recognition by immune cells.
Which structure, attached to the cecum, is in an ideal location to destroy bacteria before they breach the intestinal wall?
appendix
Which of the following is NOT a method that maintains lymph flow? valves in lymph vessel walls breathing skeletal muscle contraction capillary smooth muscle contraction
capillary smooth muscle contraction
lymph nodes are surrounded by the fibrous
capsule
dendritic cell
captures antigens and brings them back to lymph nodes
Only lymphatic collecting ducts transport what
chyle (which is a term for fatty lymph)
What region of the lymph node contains follicles filled with dividing B cells?
cortex
lymph nodes contains specific tissues called the
cortex and medulla
What is the purpose of red pulp?
destruction of worn-out red blood cells and bloodborne pathogens
lymph nodes are served by fluid-conducting vessels at the helium called the
efferent lymph vessels
reticular cell description and function
fibroblast-like cell that produces the reticular fiber stroma
When B lymphocytes are dividing rapidly, the __________ of the lymphoid tissue enlarge(s).
germinal centers
Where is the spleen located?
in the left side of the abdominal cavity just beneath the diaphragm and curled around the anterior aspect of the stomach