CH 21 lymph and immune system

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 on the surface of infected lymph vessels has become inflamed and congested with blood.

The immune system cell type that is preferentially destroyed by the Epstein-Barr virus in mononucleosis is the

B lymphocyte.

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?

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." Specifically, this refers 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 have precapillary sphincters that regulate drainage of lymph from tissues.

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

We build up many varieties of memory lymphocytes during childhood, providing immunity to more and more antigens during adulthood.

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.

Lymph vessels drain lymph from all the lymphoid organs (simply because lymph vessels drain almost all organs of the body). However, lymph vessels enter (empty into) only one type of lymphoid organ. The only organ with such afferent lymph vessels is

a lymph node.

The distal region of the small intestine contains clumps of lymph follicles called

aggregated lymphoid follicles.

A bubo is

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

B lymphocytes are to ________ as T lymphocytes are to ________.

antibodies; programmed cell death

The lymph trunk that drains the thoracic organs is called the

bronchomediastinal trunk.

Lymphatic vessels perform all of the following functions except

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 has the responsibility of presenting foreign antigens to lymphocytes?

dendritic cell

The largest kind of lymphatic vessel is a lymphatic

duct.

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

in bones and bone marrow.

In lymph nodes, follicles are always located

in the cortex.

Lymphatic ducts deliver lymph to the cardiovascular system proximal to the

internal jugular and subclavian veins.

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 connective tissue.

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

lumbar trunks

Structures comprised of endothelial cells separated by flaplike minivalves that are opened as fluid accumulates in peripheral tissue describes

lymph capillaries

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

lymph nodes

Which of the following is not a part of MALT?

lymphocytes in the spleen

Masses of lymphoid tissue within a lymph node.

lymphoid follicles

The lymphatic capillaries are

more permeable than blood capillaries.

Given that 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)?

one

Because the appendix is a narrow tube, it 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?

red blood cells

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

right lymphatic duct

Which lymphatic structure drains lymph from the right upper limb?

right subclavian duct

Lymphatic capillaries are present in

skin.

Recycles red blood cells and initiates immune responses.

spleen

The ________ stores blood platelets.

spleen

The largest lymphoid organ.

spleen

Which of the following lymphoid structures have a hilum?

spleen and lymph nodes

Macrophages that destroy aged and defective blood cells from circulation are present in the ________ of the spleen.

splenic cords

Edema is

the accumulation of excess tissue fluid in loose connective tissue.

) In humans, B lymphocytes originate in

the bone marrow.

) In humans, T lymphocytes originate in

the red bone marrow.

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

the thymus

Lymph capillaries differ from blood capillaries in all of the following ways except that

their walls consist of endothelial cells.

Lymphoid tissue contains all of the following elements except

thick collagen fibers.

Begins at the cisterna chyli

thoracic duct

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

thoracic duct

Blockage of the ________ duct would prevent drainage only from the ________ and lumbar trunks.

thoracic; intestinal

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

All of the following mechanisms help move lymph through the lymphatic vessels except

tiny lymph hearts.

Lymphoid organs located in the mucosal lining of the pharynx.

tonsils

) Crypts of the tonsils

trap bacteria and particulate matter.

In the spleen, lymphoid tissue is confined to the

white pulp.