Chapter 16: The Lymphatic System and Lymphoid Tissue

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Chapter 16:The Lymphatic Systemand Lymphoid Tissue


Cohen: Memmler’s The Human Body in Health and Disease

Overview



Key Terms

adenoid lymphadenopathy lymphoma

chyle lymphangitis spleen

lymph lymphatic duct thymus

lymphadenitis lymph node tonsil



The Lymphatic System

• System of tissues and vessels

• Scattered throughout the body

• Services almost all regions



Functions of the Lymphatic SystemLearning Outcome

1.List the functions of the lymphatic system.



Functions of the Lymphatic System

Three Main Functions

•Fluid balance (lymph)

•Protection from infection

•Absorption of fats



Functions of the Lymphatic System

✓Checkpoint

16-1 What are the three functions of the lymphaticsystem?



Lymphatic Circulation

Learning Outcomes

2.Explain how lymphatic capillaries differ from blood capillaries.

3.Name the two main lymphatic ducts and describe the area drained by each.




• One-way system

• Begins in tissues

• Ends in bloodstream



Figure 16-1 The lymphatic system in relation to the cardiovascular system.

What type of blood vessel receives lymph collected from the body?




Lymphatic Capillaries

•Capillary walls (endothelium) are flattened epithelial cells.

•They are more permeable than blood capillaries.

•Overlapping cells form one-way valves.

•They arise blindly (closed at one end).

•Lacteals absorb digested fats.



Figure 16-2 Lymphatic drainage in the tissues.




Lymphatic Vessels

•Superficial and deep sets

•Right lymphatic duct

•Thoracic duct (left lymphatic duct)

– Cisterna chyli



Figure 16-3 Vessels and nodes of the lymphatic system.

What are some nodes that receive lymph drainage from the breast?




Movement of Lymph

•Movement of lymph toward heart caused by:

– Valves in lymphatic vessels

– Contraction of lymphatic vessels

– Skeletal muscle contraction

– Breathing






✓Checkpoints

16-2 What are the two differences between bloodcapillaries and lymphatic capillaries?

16-3 What are the two main lymphatic vessels?




?Pop Quiz

16.1 Which of the following is NOT characteristic of lymphatic vessels?

A) They have thin walls.

B) They are blind-ended.

C) They can contract to propel lymph.

D) They transport lymph to the tissues.




?Pop Quiz Answer

16.1 Which of the following is NOT characteristic of lymphatic vessels?

A) They have thin walls.

B) They are blind-ended.

C) They can contract to propel lymph.

D) They transport lymph to the tissues.



Lymphoid Tissue

Learning Outcome

4.List the major structures of the lymphatic system and give the locations and functions of each.



Lymphoid Tissue

• Distributed throughout the body

• Makes up specialized organs of lymphatic system



Figure 16-5 Location of lymphoid tissue.



Lymphoid Tissue

Lymph Nodes

•Cervical nodes

•Axillary nodes

•Tracheobronchial

•Mesenteric nodes

•Inguinal nodes



Figure 16-3 Vessels and nodes of the lymphatic system.

What are some nodes that receive lymph drainage from the breast?



Figure 16-4 Lymph nodes.

What type of lymphatic vessel carries lymph into a node? What type of lymphatic vessel carries lymph out of a node?



Lymphoid Tissue

The Spleen

•Cleanses blood

– Filtration

– Phagocytosis

•Destroys old red blood cells

•Produces red blood cells before birth

•Is a reservoir for blood



Lymphoid Tissue

The Thymus

•Plays a key role in early immune system development

•Produces thymosin

– Develops T-lymphocyte cells

– Promotes lymphocyte growth

– Promotes lymphoid tissue activity

•Shrinks after puberty



Lymphoid Tissue

The Tonsils

•Remove contaminants and trap pathogens

•Palatine tonsils

•Pharyngeal tonsil (adenoids)

•Lingual tonsils

•Surgery to treat if recurrent infection or enlarged tonsils make swallowing or breathing difficult



Figure 16-6 Location of the tonsils.



Lymphoid Tissue

Other Lymphoid Tissue

•Appendix

•Mucosal-associated lymphoid tissue (MALT)

•Gut-associated lymphoid tissue (GALT)





Lymphoid Tissue

✓Checkpoints

16-4 What is the function of the lymph nodes?

16-5 What is filtered by the spleen?

16-6 What kind of immune system cells develop in the thymus?

16-7 What is the general location of the tonsils?



Lymphoid Tissue

?Pop Quiz

16.2 Lymph from the arm and breast passes through which of the following?

A) Inguinal nodes

B) Cervical nodes

C) Axillary nodes

D) Tracheobronchial nodes



Lymphoid Tissue

?Pop Quiz Answer

16.2 Lymph from the arm and breast passes through which of the following?

A) Inguinal nodes

B) Cervical nodes

C) Axillary nodes

D) Tracheobronchial nodes



Disorders of the Lymphatic System

Learning Outcome

5.Describe the major lymphatic system disorders.



Disorders of the Lymphatic System and Lymphoid Tissue

Disorders Related to Infection

● Lymphadenopathy

● Lymphadenitis

● Infectious mononucleosis

Lymphedema

● Elephantiasis



Figure 16-7 Infectious mononucleosis.



Figure 16-8 Lymphangitis.






• Splenomegaly

• Lymphoma

– Hodgkin lymphoma

– Non-Hodgkin lymphoma



Figure 16-9 Reed-Sternberg cell.




✓Checkpoints

16-8 What is lymphadenopathy?

16-9 What is lymphoma and what are the two examplesof malignant lymphoma?




?Pop Quiz

16.3 What is Hodgkin lymphoma?

A) A benign tumor of the lymph nodes

B) A malignant tumor of the lymph nodes

C) A benign tumor of the spleen

D) A malignant tumor of the spleen




?Pop Quiz Answer

16.3 What is Hodgkin lymphoma?

A) A benign tumor of the lymph nodes

B) A malignant tumor of the lymph nodes

C) A benign tumor of the spleen

D) A malignant tumor of the spleen



Case Study

Learning Outcome

6. Describe the spleen’s functions and the consequences of its removal.



Case Study

Functions of the Spleen

•Filters blood

•Removes worn-out old blood cells

•Acts as a large lymph node, detecting and fighting disease-causing organisms

Consequences of Splenectomy

•Liver will take over blood filtration and RBC removal

•Greater risk of infection



Word Anatomy

Learning Outcome

7.Show how word parts are used to build words related to the lymphatic system.



Word Anatomy



Documents

Chapter 16: The Lymphatic System and Lymphoid Tissue