The Lymphatic System (Chapter 20 A&P)

How is the skeletal system tied to the lymphatic system?

1. The lymphatic system removes excess fluids in the periosteal. 2. The lymphocytes protect the bones from pathogens. 3. Parts of the skeletal system produce the lymphocytes found in the lymphatic system.

Which of the following is not a function of the lymphatic system? A) draining excess interstitial fluid B) carrying out immune responses C) transporting dietary fats D) transporting respiratory gases

D) transporting respiratory gases

How does the lymphatic system both help and hinder the spread of cancer through the body?

Lymph nodes help rid the body of cancer cells by immune mechanisms. Lymph vessels may also be used to spread cancer cells throughout the body if immunity is not effective against the cancer cells.

Which of the following would not be classified as a lymphatic structure? A) pancreas B) spleen C) tonsils D) Peyer's patches of the intestine

A. pancreas

Functions of the spleen include all of those below except ______. A) removal of old or defective blood cells from the blood B) forming crypts that trap bacteria C) storage of blood platelets D) storage of iron

B) forming crypts that trap bacteria

Select the correct statement about lymphoid tissue. A) Once a lymphocyte enters the lymphoid tissue, it resides there permanently. B) Lymphoid macrophages secrete antibodies into the blood. C) Lymphoid tissue is predominantly reticular connective tissue. D) T lymphocytes act by ingesting foreign substances.

C) Lymphoid tissue is predominantly reticular connective tissue

Which of the following are functions of lymphoid tissue? A) house and provide a proliferation site for lymphocytes B) house and provide a proliferation site for neutrophils C) furnish an ideal surveillance vantage point for lymphocytes and macrophages D) A and C

D) A and C

What is the consequence of obstruction of the lymphatics?

Obstruction of the lymphatics results in edema distal to the obstruction.

Peyer's patches are found in the ______.

ileum of the small intestine

Highly specialized lymph capillaries called ______ are present in the villi of the intestinal mucosa.

lacteals

The thoracic duct of the lymphatic system empties into the ________.

left subclavian vein

The tonsils located at the base of the tongue are the ________.

lingual tonsils

Small organs associated with lymphatic vessels are termed _________.

lymph nodes

Which cell becomes immunocompetent due to thymic hormones?

lymphocytes

Hassall's corpuscles are always found in the lighter-colored ________ regions of the thymus.

medullary

The lymphatic capillaries are ______.

more permeable than blood capillaries

Where are the lymph node aggregations most dense?

near the body surface in the inguinal, axillary, and cervical regions of the body

Antibodies that act against a particular foreign substance are released by _______.

plasma cells

Which lymphatic structure drains lymph from the right upper limb and the right side of the of the head and thorax?

right lymphatic duct

When the lymphatic structures are blocked due to tumors, the result is _______.

severe localized edema distal to the blockage

Both lymph and venous blood flow are both dependent on _______.

skeletal muscle contractions and differences in thoracic pressures due to respiratory movement

A sentinel node is ______.

the first node to receive lymph from an area suspected to be cancerous

Lymphoid tissue that appears as a swelling of the mucosa in the oral cavity is called a(n) _________.

tonsil

The ______ are the simplest lymphoid organs and are found at the entrance to the pharynx.

tonsils

Lymphatic ________ are formed from the union of the largest collecting vessels.

trunks

The ________ pulp of the spleen forms cuffs around the central arteries.

white

Lymph leaves a lymph node via ______.

efferent lymphatic vessels

How do the lymph capillaries differ from blood capillaries?

Although similar to blood capillaries, lymphatic capillaries differ structurally in the following ways: (1) The endothelial cells forming the walls of lymphatic capillaries are not tightly joined. Their edges loosely overlap one another, forming flap like mini-valves. (2) Bundles of fine filaments anchor the endothelial cells to surrounding structures so that any increase in interstitial fluid volume separates the cell flaps, exposing gaps in the wall rather than causing the lymphatic capillary to collapse.

Select the correct statement about lymphocytes. A) The two main types are T cells and macrophages. B) B cells produce plasma cells, which secrete antibodies into the blood. C) T cells are the precursors of B cells. D) T cells are the only form of lymphocyte found in lymphoid tissue.

B) B cells produce plasma cells, which secrete antibodies into the blood.

Which of the following is not a mucosa-associated lymphatic tissue? A) tonsil B) thymus C) Peyer's patch D) appendix

B) thymus

What is the special role of the thymus gland?

By secreting hormones, the thymus gland causes T lymphocytes to become immunocompetent.

Which of the following is not a function of lymph nodes? A) act as lymph filters and activate the immune system B) produce lymphoid cells and granular WBCs C) produce lymph fluid and cerebro-spinal fluid D) serve as antigen surveillance areas

C) produce lymph fluid and cerebro-spinal fluid

Which of the following is not a normal component of lymph? A) water B) plasma proteins C) red blood cells D) ions

C) red blood cells

Lymph capillaries are absent in all but which of the following? A) bones and teeth B) bone marrow C) CNS D) digestive organs

D) digestive organs

Digestive tract-associated lymphatic tissue includes all of the following except ________. A) Peyer's patches B) palatine tonsils C) lingual tonsils D) islets of Langerhans

D) islets of Langerhans

Large clusters of lymph nodes occur in all of the following locations except the ________. A) inguinal region B) cervical region C) axillary region D) lower extremities

D) lower extremities

Which of the following is not a method that maintains lymph flow? A) skeletal muscle contraction B) breathing C) valves in lymph vessel walls D) smooth muscle contraction

D) smooth muscle contraction

Select the correct statement about lymph transport. A) Under normal conditions, lymph vessels are very high-pressure conduits. B) Lymph transport is faster than that occurring in veins. C) Lymph transport is only necessary when illness causes tissue swelling. D) Lymph transport depends on the movement of adjacent tissues, such as skeletal muscles.

Lymph transport depends on the movement of adjacent tissues, such as skeletal muscles

Characterize lymph transport in terms of rate, volume, and ability to change.

Lymph transport is sporadic and much slower than that occurring in veins. About 3 liters of lymph enters the bloodstream in a 24-hour period. An increase in physical activity will cause lymph flow to increase, balancing the greater rate of fluid outflow from the vascular system.

Describe the mechanisms by which lymphatic fluid is moved through the lymphatics.

Lymphatic fluid is moved through the lymphatics by the milking action of active skeletal muscles, pressure changes within the thorax during breathing, valves to prevent backflow, and pulsation of adjacent arteries.

The appendix, tonsils, and Peyer's patches are examples of ______.

MALT

Explain the term MALT. What is its function?

MALT is an acronym for mucosa-associated lymphatic tissue. It includes Peyer's patches, the appendix, and the tonsils in the digestive tract, lymphoid follicles in the walls of the bronchi, and genitourinary tract. Collectively, MALT protects passages open to the exterior from foreign matter entering them.

How does the structure of a lymph node allow lymphocytes and macrophages to perform their protective function?

Macrophages and lymphocytes are located in lymph nodes. Macrophages ingest microorganisms and cellular debris. Lymphocytes monitor the lymphatic stream for the presence of antigens and mount an immune response. Because there are fewer efferent vessels draining the node than afferent vessels that feed it, the flow of lymph through the node stagnates somewhat, allowing time for the lymphocytes and macrophages to work.

Name the tonsils and state their body locations.

Palatine tonsils are located on either side at the posterior end of the oral cavity. The lingual tonsils lie at the base of the tongue. The pharyngeal tonsils are in the posterior wall of the nasopharynx.

The distal portion of the small intestine contains clumps of lymph follicles called ______.

Peyer's patches

The thymus is the only lymphoid organ that does not _____.

directly fight antigens

List the functions of the spleen.

The spleen's main functions are to remove aged or defective blood cells and platelets from the blood and to store or release some of the breakdown products of RBCs to the blood for processing by the liver. Other functions include acting as a blood filter and reservoir, serving as a site for erythrocyte production in developing embryos, storing blood platelets, and providing a site for lymphocyte proliferation and immune surveillance and response.

What effect does age have on the thymus?

The thymus initially increases in size and then decreases in size from adolescence through old age.

Describe the structural and functional relationship of the vessels of the blood vascular system and the lymphatic system.

Vessels of the blood vascular system are relatively high-pressure conduits compared to vessels of the lymphatic system. The same mechanisms that promote venous return in blood vessels act within lymphatic vessels. Because lymphatics are usually packaged together in connective tissue sheaths with blood vessels, the pulsating expansions of the nearby arteries also promote lymph flow

What is bubo?

an infected lymph node

The thymus is most active during ______.

childhood

Tonsils have blind-ended structures called ________.

crypts