Chapter 21 lymphatic system and lymphnoid organs and tissues

How is the skeletal system tied to the lymphatic system?

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

14) 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.

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

30) 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

Where are the lymph node aggregations most dense?

Lymph node aggregations are most dense near the body surface in the inguinal, axillary, and cervical regions of the body

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.

26) The tonsils located at the base of the tongue are the ________. A) lingual tonsils B) palatine tonsils C) pharyngeal tonsils D) Peyer's tonsils

A) lingual tonsils

8) The lymphatic capillaries are ________. A) more permeable than blood capillaries B) less permeable than blood capillaries C) as permeable as blood capillaries D) completely impermeable

A) more permeable than blood capillaries.

2) 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

17) Lymphoid tissue that appears as a swelling of the mucosa in the oral cavity is called a(n) ________. A) tonsil B) thymus C) Peyer's patch D) appendix

A) tonsil

5) The thymus is most active during ________. A) fetal development B) childhood C) middle age D) old age

B) childhood

12) 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

19) Peyer's patches are found in the ________. A) duodenum of the small intestine B) ileum of the small intestine C) large intestine D) jejunum of the small intestine

B) ileum of the small intestine

1) Small organs associated with lymphatic vessels are termed __A) lymph follicles B) lymph nodes C) axillary nodes D) cisterna chyli______.

B) lymph nodes

11) Which cells become immunocompetent due to thymic hormones? A) basophils B) lymphocytes C) macrophages D) monocytes

B) lymphocytes.

9) Antibodies that act against a particular foreign substance are released by ________. A) T lymphocytes B) plasma cells C) lymph nodes D) medullary cords

B) plasma cells

16) 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.

What is the consequence of obstruction of the lymphatics?

Obstruction of the lymphatics results in edema distal to the obstruction

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

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

medullary

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

trunks

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

white

10) Lymph leaves a lymph node via ________. A) efferent lymphatic vessels B) afferent lymphatic vessels C) the cortical sinus D) the subscapular sinus

.A) efferent lymphatic vessels

3) The distal portion of the small intestine contains clumps of lymph follicles called ________. A) islets of Langerhans B) Peyer's patches C) rugae D) villi

B) Peyer's patches

What is the special role of the thymus gland?

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

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 flaplike minivalves. (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.

1) The ________ are the simplest lymphoid organs and are found at the entrance to the pharynx.

Answer: tonsils

15) 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.

13) When the lymphatic structures are blocked due to tumors, the result is ________. A) shrinkage of tissues distal to the blockage due to inadequate delivery of lymph B) severe localized edema distal to the blockage C) increased pressure in the lymphatics proximal to the blockage D) abnormally high lymph drainage from the distal region

B) severe localized edema distal to the blockage

Both lymph and venous blood flow are heavily dependent on A) the pumping action of the heart B) skeletal muscle contractions and differences in thoracic pressures due to respiratory movement C) contraction of the vessels themselves D) two-way valves________.

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

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

B) thymus

31) 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

27) 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

6) Which lymphatic structure drains lymph from the right upper limb and the right side of the head and thorax? A) lumbar trunk B) thoracic duct C) right lymphatic duct D) cisterna chyli

C) right lymphatic duct

29) 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

7) What effect does age have on the size of the thymus? A) The size of the thymus increases continuously from birth to death. B) The size of the thymus decreases continuously from birth to death. C) The thymus is not affected by age. D) The thymus initially increases in size and then decreases in size from adolescence through old age.

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

21) What is a bubo? A) a wall in a lymph node B) a lobe of the spleen C) an infected Peyer's patch D) an infected lymph node

D) an infected lymph node

20) 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

22) The thymus is the only lymphoid organ that does not: A) have lymphocytes B) produce hormones C) have a cortex and medulla D) directly fight antigens

D) directly fight antigens

24) 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

23) 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

25) 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

28) A sentinel node is ________. A) a lymph node found in the intestinal lamina propria B) the first node at the junction of all the lumbar trunks C) a small node in the spleen D) the first node to receive lymph from an area suspected to be cancerous

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

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.

2) 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.

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.

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

Tonsils have blind-ended structures called

crypts