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