Anatomy Ch 21

A germinal center arises from a single activated lymphocyte; how many different kinds of antibodies are secreted by a single germinal center and by the plasma cells it produces?

1

The Epstein-Barr virus (which causes mononucleosis) preferentially destroys which of these cell types?

B lymphocytes.

Which of the following would best explain why most people are sick more often as children than as adults in their 20s through 50s?

During childhood, we build up many varieties of memory lymphocytes, which provide immunity to more and more antigens during adulthood.

A person with many enlarged lymph nodes that do not feel tender or sore is most likely to have

Hodgkin's lymphoma.

Which of the following statements about the right lymph duct is false? Not all people have one. This duct and its tributaries drain the superior right quarter of the body. It empties into the thoracic duct. It forms from the union of a jugular, subclavian, and bronchomediastinal trunk.

It empties into the thoracic duct.

Lymphoid tissue associated with the digestive, respiratory, urinary, and reproductive tracts.

MALT

One location where lymphoid tissue is found is "in the frequently infected mucous membranes of the digestive, respiratory, urinary, and reproductive tracts." This description refers specifically to

MALT

By secreting hormones, the thymus causes which cells to become immunocompetent?

T lymphocytes

Which of these statements regarding lymph capillaries is false? They begin as closed-ended tubes. They have precapillary sphincters that regulate drainage of lymph from tissues. They lack barriers to stop cancer cells from entering the lymphatic system. They unite with each other to form collecting vessels.

They have precapillary sphincters that regulate drainage of lymph from tissues.

Is it possible for lymphocytes to gain immunocompetence in the thymus of an 82-year-old person?

Yes, but fewer than in youth.

A lymphoid nodule is

a cluster of densely packed lymphocytes.

A bubo is

an infected lymph node containing a large number of pathogens that are trapped in the node but not destroyed

Any molecule that induces an immune response from a lymphocyte is called a(n)

antigen

In humans, B lymphocytes originate in

bone marrow

Lymphatic vessels perform all of the following functions except returning excess tissue fluid to the bloodstream. returning leaked blood proteins to the bloodstream. transporting digested fats. carrying blood.

carrying blood.

The thymus is most active during

childhood

The sinuses within lymph nodes

contain macrophages living along a reticular fiber network.

Blind-end invaginations of tonsil epithelium that trap bacteria and particulate matter.

crypts

Which cell type has the responsibility of presenting foreign antigens to lymphocytes?

dendritic cell

The largest type of lymphatic vessel is a lymphatic

duct.

Lymphatic vessels in the ________ collect cerebrospinal and interstitial fluid from the sub-arachnoid space.

dura mater

Lymph leaves a lymph node via

efferent lymphatic vessels

In a histological cross section through an artery, a vein, and a lymphatic vessel, one can recognize the lymphatic vessel because it

has the thinnest walls.

Which cell secretes cytokines that will stimulate the proliferation of other types of immune cells?

helper CD4+ T lymphocyte

The immune system cell type that is preferentially destroyed by the AIDS virus is the

helper T lymphocyte.

Clusters of lymph nodes occur in all of the following sites except along the aorta. in the mediastinum. in bones and bone marrow. in the inguinal region.

in bones and bone marrow.

In lymph nodes, follicles are always located

in the cortex

The lymph trunk that contains chyle and is unpaired is the

intestinal.

Set of lymphatic capillaries that collect fat-laden fluids from the intestinal tract.

lacteals

The tonsil located on the posterior surface of the tongue is the ________ tonsil.

lingual

Which of the following is not classified as a lymphoid organ?

liver

Lymphocytes attack antigens mostly in lymphoid organs (except the thymus) and in

loose CT

The paired lymph trunks that carry lymph from the lower limbs are the

lumbar trunks.

_______ are structures comprised of endothelial cells separated by flaplike minivalves, which open as fluid accumulates in peripheral tissue.

lymph capillaries

Lymph vessels drain lymph from all the lymphoid organs, as they do from almost all organs of the body. However, afferent lymph vessels enter (empty into) only one type of lymphoid organ, the

lymph node

Small, bean-shaped organs abundant in the cervical, axillary, and inguinal regions.

lymph nodes

Which of the following is not a part of MALT? lymphoid tissue in the appendix lymphoid tissue in the tonsils aggregated lymphoid nodules lymphocytes in the spleen

lymphocytes in the spleen

Masses of lymphoid tissue within a lymph node.

lymphoid follicles

The lymphatic capillaries are

more permeable than blood capillaries.

The appendix is a narrow tube which traps microorganisms from the digestive tract, and these microorganisms enter its wall and activate memory lymphocytes for long-term immunity. Another immune organ that traps microorganisms is the

palatine tonsil

Which of the following cells are the largest producers of antibodies?

plasma cells

The bulges that give lymph vessels a string-of-beads appearance are really

pockets for valves.

Which of the following is not a normal component of lymph? water plasma proteins red blood cells ions

rbc

Lymphoid tissue is basically ________ connective tissue.

reticular

Large lymphatic vessel that, if present, is comprised of the right subclavian trunk, right jugular trunk and right bronchomediastinal trunk.

right lymphatic duct

The ________ stores blood platelets.

spleen

The largest lymphoid organ is the

spleen

Which of the following recycle(s) red blood cells and initiates immune responses?

spleen

Edema is

the accumulation of excess tissue fluid in loose connective tissue.

In humans, T lymphocytes originate in

the red bone marrow.

A patient with lymphangitis presents with visible red lines on the skin that are tender to the touch. The best explanation for this sign is that

the vasa vasorum of the infected lymph vessels has become inflamed.

Lymph capillaries differ from blood capillaries in all of the following ways except that they are more permeable than most blood capillaries. they carry lymph instead of blood. they are blind-ended. their walls consist of endothelial cells.

their walls consist of endothelial cells.

Begins at the cisterna chyli.

thoracic duct

Blockage of the ________ would prevent drainage from both the intestinal and lumbar trunks.

thoracic duct

Duct of the lymphatic system that drains the body's entire lower half.

thoracic duct

T cells gain immunocompetence in this lymphoid organ.

thymus

The lymph organ that lies in the superior part of the thoracic mediastinum is the

thymus

The lymphoid organ that atrophies with age

thymus

This organ has a superficial cortex filled with lymphocytes and an inner medulla with few lymphocytes and a sizable number of degenerating epithelial reticular cells.

thymus

Two-lobed lymphoid organ located posterior to the sternum.

thymus

Which of the following lymphoid organs does not directly fight antigens?

thymus

Lymphoid organs located in the mucosal lining of the pharynx.

tonsils

The crypts of the tonsils

trap bacteria and particulate matter

The muscular ________of the lymphatic vessels contract(s) to help propel the lymph.

tunica media

In the spleen, lymphoid tissue is confined to the

white pulp