Download Chapter 7 Lymphatic System and Immunity

CHAPTER 8
LYMPHATIC AND IMMUNE SYSTEMS
BEHAVIORAL OBJECTIVES
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List three functions of the lymphatic system. [8.1, p.146]
Describe the structure of lymphatic vessels. [8.1, p.146, Fig. 8.2]
Name and locate the lymphoid organs. [8.1, p.147, Fig. 8.3]
Explain the structure and purpose of lymph nodes. [8.1, p.147]
Discuss the functions of the spleen, and of the white and red pulp it contains. [8.1, p.147]
Describe how the thymus gland and red bone marrow participate in immunity. [8.1, p.148]
Describe barriers to entry, the inflammatory reaction, natural killer cells, and protective proteins as agents of
nonspecific immunity. [8.2, pp.148-150, Figs. 8.4 & 8.5]
Compare the origin, maturation, and function of B cells and T cells. [8.3, pp.150-151]
Tell how a T cell recognizes an antigen. [8.3, p.150]
Explain how and where B cells undergo clonal selection and expansion. [8.3, p.151, Fig. 8.6]
Describe the general structure of an antibody, and state a function for the variable and constant regions. [8.3,
p.152, Fig. 8.7]
Describe the five classes of antibodies. [8.3, p.152, Table 8.1]
Describe the dangers pesticides pose for the immune system. [8.3, p.153, Ecology Focus]
Explain clonal selection as it applies to T cells. [8.3, p. 154, Fig. 8.8]
List the different types of T cells, and give the action of each. [8.3, pp.154-155]
Differentiate between active and passive immunity. [8.4, pp.156-158]
Describe how monoclonal antibodies are produced. [8.4, p. 158, Fig. 8.12]
List three types of immunological side effects, and relate them to the function of the immune system. [8.5,
pp.158-160]
Describe the role of the immune system in homeostasis. [8.6, p.160]
Discuss how the lymphatic and immune systems work with other body systems to maintain homeostasis. [8.6,
pp.160-161, Human Systems Work Together]
Understand and use the bold-faced and italicized terms included in this chapter. [Understanding Key Terms,
p.163]
EXTENDED LECTURE OUTLINE
8.1 Lymphatic System
The lymphatic system consists of lymphatic vessels and lymphoid organs.
Lymphatic Vessels
The lymphatic vessels collect fat molecules at intestinal villi and excess tissue fluid at blood capillaries, and carry
lymph to the subclavian veins.
Lymphoid Organs
Lymphocytes are produced and accumulate in the lymphoid organs (red bone marrow, lymph nodes, spleen, and
thymus gland). Lymph is cleansed of pathogens and/or their toxins in lymph nodes, and blood is cleansed of
pathogens and/or their toxins in the spleen. T lymphocytes mature in the thymus, while B lymphocytes mature in the
red bone marrow where all blood cells are produced. White blood cells are necessary for nonspecific and specific
defenses.
Mader VRL CD-ROM
Image 0154l.jpg (Fig. 8.1)
Image 0155l.jpg (Fig. 8.2)
Image 0156al.jpg (Fig. 8.3)
Image 0156bl.jpg (Fig. 8.3)
Dynamic Human 2.0 CD-ROM
Lymphatic/Anatomy/Gross Anatomy
Lymphatic/Anatomy/Microscopic Components
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Dynamic Human 2.0 CD-ROM, con’t.
Lymphatic/Explorations/Lymph Movement
Lymphatic/Histology/Lymph Node
Lymphatic/Histology/Peyer’s Patches
Lymphatic/Histology/Spleen
Life Science Animations VRL 2.0
Lymphatic/Histology/Thymus
Animal Biology/Immune System/ Lymphatic System
Animal Biology/Immune System/The Immune System
Mader ESP Modules Online
Animals/Lymph and Immunity/Lymph System
Transparencies
115 (Fig. 8.2)
116 (Fig. 8.3)
8.2 Nonspecific Defenses
Immunity involves nonspecific and specific defenses.
Barring Entry
Skin, mucous membranes, oil glands, and an acidic stomach all contribute to keeping pathogens from entering the
body.
Inflammatory Reaction
Redness, heat, swelling, and pain characterize the inflammatory reaction. The release of histamine and kinins from
damaged tissue cells and mast cells bring about redness and swelling. A rise in temperature increases phagocytosis
by neutrophils and macrophages. The swollen area stimulates free nerve endings, causing the sensation of pain.
Natural Killer Cells
Natural killer cells attack virus-infected cells and tumor cells by cell-to-cell contact.
Protective Proteins
Complement which includes various plasma proteins assist nonspecific immunity. They amplify the inflammatory
reaction by attracting phagocytes and promoting phagocytosis. Some complement proteins form pores in the surface
of bacteria and thereby cause them to burst.
Mader VRL CD-ROM
Image 0157l.jpg (Fig. 8.4)
Image 0158l.jpg (Fig. 8.5)
Dynamic Human 2.0 CD-ROM
Lymphatic/Explorations/Fever
Lymphatic/Explorations/Inflammation
Lymphatic/Explorations/Interferon
Life Science Animations VRL 2.0
Lymphatic/Explorations/Phagocytosis
Animal Biology/Immune System/ Phagocytic Cells
Animal Biology/Immune System/Inflammatory Reaction
Animal Biology/Immune System/Fever
Animal Biology/Immune System/Complement Proteins
Animal Biology/Immune System/ Antiviral Defense
Mader ESP Modules Online
Animals/Lymph and Immunity/Nonspecific Immunity
Transparencies
117 (Fig. 8.4)
118 (Fig. 8.5)
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8.3 Specific Defenses
Specific defenses include the actions of B and T lymphocytes, along with the recognition of specific antigens.
B Cells and Antibody-Mediated Immunity
B cells mature in the bone marrow. They undergo clonal selection with production of plasma cells and memory B
cells after their specific plasma membrane receptors directly combine with a particular antigen. Plasma cells secrete
antibodies and eventually undergo apoptosis. Memory B cells remain in the body and produce antibodies if the same
antigen enters the body at a later date.
Structure of IgG
The most common type of antibody, the IgG antibody, is a Y-shaped molecule that has two binding sites
for a specific antigen.
Other Types of Antibodies
Immunoglobulins include four other types aside from IgG. They differ in structure and function as
described in Table 7.1.
T Cells and Cell-mediated Immunity
Like B cells, each T cell bears a specific receptor. However, for a T cell to recognize an antigen, the antigen must be
presented by an antigen-presenting cell (APC), usually a macrophage, along with an HLA (human lymphocyteassociated) antigen. Thereafter the activated T cell undergoes clonal expansion until the infection has been stopped.
Then most of the activated T cells undergo apoptosis. A few cells remain, however, as memory T cells.
Types of T Cells
T cells mature in the thymus. The two main types of T cells are cytotoxic T cells and helper T cells.
Cytotoxic T cells kill infected cells that bear a foreign antigen on contact; helper T cells stimulate other
immune cells and produce cytokines.
Mader VRL CD-ROM
Image 0159l.jpg (Fig. 8.6)
Image 0160l.jpg (Fig. 8.7)
Image 0161l.jpg (Fig. 8A)
Image 0162l.jpg (Fig. 8.8)
Image 0163l.jpg (Fig. 8.9)
Dynamic Human 2.0 CD-ROM
Lymphatic/Explorations/Cytotoxic T Cells
Lymphatic/Explorations/Humoral Immunity
Lymphatic/Explorations/T-Helper Cells
Life Science Animations VRL 2.0
Lymphatic/Histology/Lymphocyte(s)
Animal Biology/Immune System/ Immune Response
Recognizes Many Targets
Animal Biology/Immune System/ T-Cell Function
Animal Biology/Immune System/Clonal Selection
Animal Biology/Immune System/ Clonal Selection Theory as It
Applies to B Cells
Animal Biology/Immune System/ Clonal Selection Theory as It
Applies to T Cells
Mader ESP Modules Online
Animals/Lymph and Immunity/Specific Immunity
Transparencies
119 (Fig. 8.6)
120 (Fig. 8.7a)
121 (Fig. 8.8)
122 (Fig. 8.9b)
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8.4 Induced Immunity
Active Immunity
Vaccines are available to induce long-lived active immunity. After exposure to a vaccine, antibodies are present in
the body. The secondary response is higher than the primary response. Active immunity is long-lived because there
are memory B cells and memory T cells in the body.
Passive Immunity
Passive immunity occurs when an individual is given antibodies from an outside source. For example, nursing
passes antibodies from mother to child.
Cytokines and Immunity
Cytokines, including interferon, are used in an attempt to promote the body’s ability to recover from cancer and to
treat AIDS.
Monoclonal Antibodies
Activated B lymphocytes are fused with myeloma cells and these hybridomas produce only one type of antibody.
Monoclonal antibodies are most often used in diagnostic procedures such as pregnancy tests.
Mader VRL CD-ROM
Image 0164al.jpg (Fig. 8.10)
Image 0164bl.jpg (Fig. 8.10)
Image 0165l.jpg (Fig. 8.11)
Image 0166l.jpg (Fig. 8.12)
Dynamic Human 2.0 CD-ROM
Lymphatic/Clinical Concepts/Vaccination
Life Science Animations VRL 2.0
Animal Biology/Immune System/Vaccination
Animal Biology/Immune System/ Production of Monoclonal
Antibodies
Transparencies
123 (Fig. 8.10)
124 (Fig. 8.12)
8.5 Immunity Side Effects
Allergies
Allergic responses occur when the immune system reacts vigorously to substances not normally recognized as
foreign.
Immediate Allergic Response
Immediate allergic responses, usually consisting of coldlike symptoms, are due to the activity of antibodies.
Delayed Allergic Response
Delayed allergic responses, such as contact dermatitis, are due to the activity of T cells.
Autoimmune Diseases
An autoimmune disease occurs when T cells or antibodies mistakenly attack the body’s own cells. It’s been
suggested that insulin-dependent diabetes is an autoimmune disease.
Tissue Rejection
Rejection occurs when cytotoxic T cells bring about the destruction of foreign tissue in the body. Immunosupressive
drugs act by inhibiting the response of T cells to cytokines.
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Image 0167l.jpg (Fig. 8B)
Mader ESP Modules Online
Animals/Lymph and Immunity/Abnormalities
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8.6 Homeostasis
In general the lymphatic system and the immune system contribute to homeostasis by protecting the body from takeover by pathogens. A Human Systems Work Together box shows how the lymphatic system works with other
systems in the body to maintain homeostasis.
Mader VRL CD-ROM
Image 0168al.jpg (Fig. TA8.1)
Image 0168bl.jpg (Fig. TA8.1)
Image 0169l.jpg (Fig. TA8.2)
Case Studies Online
Biological Weapons Site Threatens to Spread Disease
Transparencies
125 (Fig. TA8.1)
126 (Fig. TA8.2)
SEVENTH EDITION CHANGES
New/Revised Text:
This was chapter 7, Lymphatic System and Immunity, in the previous edition. The introductory story was
revised to better introduce the immune system and its functions.
8.4 Induced Immunity. The immunization schedule for infants and young children has been updated to
contain the latest requirements. In Cytokines and Immunity, the explanation of the technique to activate cytotoxic T
cells to destroy cancer cells has been clarified. The explanation of the delayed allergic response has been simplified.
New/Revised Figures:
8.6 Clonal selection theory as it applies to B cells; 8.8 Clonal selection theory as it applies to T cells; 8.10b
(updated Immunization table)
New/Revised Table:
8.1; immunization table in Figure 8.10
STUDENT ACTIVITIES
Do You Suffer from Allergies?
1. Have students read the Health Focus “Immediate Allergic Responses” before coming to class. Then, survey
your class and tally the number of students who are allergic to common allergens, such as mold, dust, and
pollen. Next, ask if anyone has food allergies, and tally the number of students who have had reactions to
peanuts, wheat gluten, milk products, certain fruits (strawberries), or mushrooms. Finally, determine whether
any students are allergic to bee or wasp stings. Discuss whether students feel allergies are a nuisance or are lifethreatening.
Pesticides: Are They Needed?
2. Students should read the Ecology Focus, “Pesticide: An Asset or a Liability,” before coming to class. Several
groups, such as farmers, pesticide producers, environmentalists, and the general public are involved in this
controversy, and the class can be divided so that each group is represented. The “farmers” decide what their
needs are, and then the “pesticide producers” and the “environmentalists” try to convince the farmers that they
can meet those needs. The farmers try to find flaws in the arguments based on their needs. The “general public”
decide what their needs are and, after hearing the arguments of the pesticide producers and environmentalists,
counsel the farmers to choose the group they support. Each student writes a short article covering the event.
How Stress Affects the Immune System
3. Devise a questionnaire for your students that examines their unique responses to stress. Alternatively, hold a
class discussion, asking volunteers to describe their responses to stress in a variety of situations. What certain
people find stressful may not bother other people at all. Discuss what students find stressful (e.g., exam days,
oral reports, term papers, dating). Relocating, relationship breakups, illness, and relationships with bosses or
parents are other potential stressors.
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The stress questionnaire might go something like this (students circle answers):
Frequency of Illness
Under stress, are you:
more likely to become ill
as likely to become ill as when I am not
under stress
less likely to become ill.
Sleeping Habits
Under stress, do you:
sleep more
sleep the same amount
sleep less
What are your dreams like when you are under stress?
dream about what is stressing me
dream about the same things as usual
have nightmares
don’t dream at all
Eating Habits
Under stress, do you:
eat more and more nutritiously
eat more, usually junk food
eat the same as I always do
eat less but more nutritiously
eat less, period
Relationships with Others
Under stress, are you:
more likely to argue, yell, or be angry
likely to act pretty much the same as always
more likely to become more docile
Compile the results of class questionnaires. Discuss the outcome. Ask students whether punishing their bodies (lack
of sleep, eating junk food, etc.) during times of stress creates more stress.
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