LYMPH AND IMMUNE SYSTEM WB OLA (6)

.docx

School

Kennesaw State University *

*We aren’t endorsed by this school

Course

123

Subject

Biology

Date

Dec 6, 2023

Type

docx

Pages

19

Uploaded by brookehornsby20

Report
The Lymphatic System and Body Defenses The lymphatic system, with its many lymphoid organs and vessels derived from veins of the cardiovascular system, is a rather strange system. Although both types of organs help to maintain homeostasis, these two elements of the lymphatic system have substantially different roles. The lymphatic vessels keep the cardiovascular system functional by maintaining blood volume. The lymphoid organs help defend the body from pathogens by providing operating sites for phagocytes and cells of the immune system. The immune system, comprising the body's specific defense system , is a unique functional system made up of billions of individual cells, most of which are lymphocytes. The sole function of this defensive system is to protect the body against an incredible array of pathogens. In general, these "enemies" fall into three major camps: (1) microorganisms (bacteria, viruses, and fungi) that have gained entry into the body, (2) foreign tissue cells that have been transplanted (or, in the case of red blood cells, infused) into the body, and (3) the body's own cells that have become cancerous. The result of the immune system's activities is immunity, or specific resistance to disease. The body is also protected by a number of nonspecific defenses provided by intact surface membranes such as skin and mucosae, and by a variety of cells and chemicals that can quickly mount an attack against foreign substances. The specific and nonspecific defenses enhance each other's effectiveness. Chapter 12 tests your understanding of the functional roles of the various lymphatic system elements, and both the nonspecific and specific body defenses. THE LYMPHATIC SYSTEM Lymphatic Vessels 1 . Complete the following statements by writing the missing terms in the answer blanks. 1. 2. 3. 4. 5. 6. Although the cardiovascular system has a pump (the heart) and arteries, veins, and capillaries, the lymphatic system lacks two of these structures: the (1) and (2) . Like the (3) of the cardiovascular system, the vessels of the lymphatic system are equipped with (4) to prevent backflow. The lymphatic vessels act primarily to pick up leaked fluid, now called (5) , and return it to the bloodstream. About (6) of the fluid is returned every 24 hours.
2 . Figure 12-1 provides an overview of the lymphatic vessels. In part A, the relationship between lymphatic vessels and the blood vessels of the cardiovascular system is depicted schematically. Part B shows the different types of lymphatic vessels in a simple way. Label these specific structures in part B: A. Lymph capillaries C. Lymphatic collecting vessels E. Valves B. Lymph duct D. Lymph node F. Vein 3. Highlight the term that does not belong in each of the following groupings. 1. Blood capillary Lymph capillary Blind-ended Permeable to proteins 2. Edema Blockage of lymphatics Elephantiasis Inflammation Abundant supply of lymphatics 3. Skeletal muscle pump Flow of lymph Respiratory pump High-pressure gradient Action of smooth muscle cells in walls of lymph vessels 4. Minivalves Endothelial cell overlap Impermeable Lymphatic capillaries
Lymph Nodes and Other Lymphoid Organs 4. Match the terms in Column B with the appropriate descriptions in Column A. More than one choice may apply in some cases. Column A Column B 1. The largest lymphatic organ; a blood reservoir A. Lymph Nodes 2. Filter lymph B. Peyer’s patches 3. Particularly large and important during youth; C. Spleen produces hormones that help to program the immune system D. Thymus 4. Collectively called MALT 5. Removes aged and defective red blood cells E. Tonsils 6. Prevents bacteria from breaching the intestinal wall 5. Figure 12-2 depicts several different lymphoid organs. Label all lymphoid organs indicated by a leader line (red text boxes) and label (blue text boxes) the sites where the axillary, cervical, and inguinal lymph nodes would be located. Color the lymphoid organs as you like, and then shade in light green the portion of the body that is drained by the right lymphatic duct (done).
6. Figure 12-3 is a diagram of a lymph node. First, using the terms with color coding circles, learn all structures in black labels on the diagram that have leader lines. Color those structures as well. Then, add arrows to the diagram to show the direction of lymph flow through the organ (done). Circle the region that would approximately correspond to the medulla of the organ (done ). Finally, answer the questions that follow. 1. Which cell type is found in greatest abundance in the germinal centers? 2. What is the function of their daughter cells, the plasma cells? 3. What major cell type in cortical areas other than the germinal centers? 4. The third important cell type in lymph nodes (usually found clustered around the medullary sinuses) are the _________________________________. These cells act as capsule Afferent lymphatic trabeculae Subscapular sinus cortex Germinal center Medullary sinus medullary cord hilus Efferent lymphatics
5. Of what importance is the fact that there are fewer efferent than afferent lymphatics associated with lymph nodes? 6. What structures assure that one-way flow of lymph through the node? 7. The largest collections of lymph nodes are found in what three body regions? 8. What is the general function of lymph nodes? BODY DEFENSES Nonspecific Body Defenses 7. The three major elements of the body’s nonspecific defense system are: the (1) , consisting of the skin and _____________________ ; defensive cells, such as (2) _____________________ and phagocytes; and a whole deluge of (3) _____________________ . 8. Indicate the sites of activity or the secretions of the nonspecific defenses by writing the correct terms in the answer blanks. 1. Lysosome is found in the body secretions called and 2. Fluids with an acid pH are found in the and 1. 2. 3.
3. Sebum is a product of the glands and acts at the surface of the 4. Mucus is produced by glands found in the respiratory and system mucosae. 9. Highlight the term that does not belong in each of the following groupings. 1. Redness Pain Swelling Itching Heat 2. Neutrophils Macrophages Phagocytes Natural killer cells 3. Inflammatory chemicals Histamine Kinins Interferon 4. Intact skin Intact mucosae Inflammation First line of defense 5. Interferons Antiviral Antibacterial Proteins 10. Match the terms in Column B with the descriptions of the nonspecific defenses of the body in Column A. More than one choice may apply. Column A Column B 1. Have antimicrobial activity A. Acids 2. Provide mechanical barriers B. Lysozyme 3. Provide chemical barriers C. Mucosae 4. Entraps microorganisms D. Mucus entering the respiratory E. Protein-digesting enzymes passages F. Sebum 5. Part of the first line of defense G. Skin 11. Describe the protective role of cilia in the respiratory tract. 12. Define phagocytosis . 1. 2. 3. 4. 5.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
  • Access to all documents
  • Unlimited textbook solutions
  • 24/7 expert homework help