Grant Sanders

Immune System Wiki Homework. (Chapter 7)

7.2 Lymphatic System
For each of the following define their function and include their role in immunity (the ability to combat disease). (p.127-128)
Red bone marrow- produces all types of blood cells, and they also produce white blood cells help fight disease.
thymus gland- The thymus gland produces thymic hormones, and if they live they attack pathogens.
Spleen- filters blood, and a person with a spleen is more open to infections.
lymph nodes- filter lymph, and doctors believe that the lymph node swells because it is fighting deadly diseases.

7.3 Nonspecific Defenses (p. 128-130)

Describe the barriers to entry and include their role in immunity
Skin and mucous membranes- Intact skin is a generally very effective physical barrier that prevents disease.
Chemical Barriers- Chemical barriers are oil glands of the skin, and it contains an antibacterial that washes bacteria from the body called lysozyme.
Resident Bacteria- A chemical barrier to infection that usually reside in the mouth, intestine, and other areas.

Define the players in the inflammatory response
Histamine- A chemical mediator released by damage tissue cells.
mast cells- cause the capillaries to dilate and become more permeable.
pus- If neutrophils die off in great quantity, they become a yellow- white substance we call pus.
cytokines- If the neutrophils are overwhelmed, they call for reinforcements by this secreting chemical mediator.
macrophages.- More powerful phagocytes than nuetrophils.

List the four steps in the inflammatory response (figure 7.9)
1. Injured tissue cells and mast cells release histamine, which causes capillaries to dilate and increases blood flow.
2. Macrophages and dendritic cells phagocytize pathogens and release cytokines, which stimulate the inflammatory response.
3. Nuertophils and monocytes squeeze through the capillary wall and phagocytize pathogens.
4. Blood clotting walls off capillary and prevents blood loss.

Describe the complement system and its role in immunity.
They are known to compliment certain immune responses, and they are composed of a number of blood plasma proteins.
Describe the membrane attack complex and its role in immunity.
They produce holes in the surface of bacteria and some viruses. Fluids and salts then enter the bacteria cell or virus to the point that they burst.
Describe interferon and its role in immunity.
Proteins produced by virus- infected cells as a warning to noninfected cells in the area. Interferons are used to treat such diseases as hepatitis C.

7.4 Specific Defenses (pp.130)
Define Antigens.
Molecules the immune system recognizes as foreign to the body.
How does specific defense differ from nonspecific defense?
Specific defenses primarily depend on B cells and T cells, were nonspecific defenses depend on all types of cells.
Which blood cells are mainly responsible for specific defense, and how do they function? (make a table like the one on page 130)
Cell Funtion

B cells- Produce plasma cells and memory cells.
Plasma cells- Produce specific antibodies.
Memory cells- Ready to produce antibodies in the future.

T cells- Regulate immune response, produce cytotoxic T cells and helper T cells.
Cytotoxic T cells- Kill virus- infected cells and cancer cells.
Helper T cells- Regulate immunity.
Memory T cells- ready to kill in the future.

7.5 Acquired Immunity (pp.136)
What is acquired immunity?
Immunity that occurs naturally through infection or is brought about artificially by medical intervention.
What is active immunity and explain an example?
The individual alone produces antibodies against an antigen.
What is passive immunity and explain an example?
The individual is given prepared antibodies via an injection.

7. 6 Hypersensitivity Reactions (pp.138-139)
When is the immune system hypersensitive?
When an individual develops allergies, suffer tissue rejection, or have an autoimmune disease.
Explain how an allergy is an example of hypersensitivity.
They are hypersensitive to substances, such as pollen, food, or animal hair, that wouldn’t usually do harm to the body.
Explain how tissue rejection is an example of hypersensitivity.
Tissue rejection is hypersensitive because it rejects certain organs such as the heart, the skin, and the kidneys.
Define autoimmune disease.
When cytotoxic T cells or antibodies mistakenly attack the body’s own cells as if they bear foreign antigens.
Define the following autoimmune diseases.
multiple sclerosis (MS)
T cell attack the myelin sheath of nerve fibers.
Various symptoms prior to death due to kidney damage from the deposition of excessive antigen- antibody complexes.
rheumatoid arthritis affects the joints.