The Immune System

Question 1

Nonspecific Immunity

Answer 1

• The body has a number of defenses in the immune system that fight off pathogens.
• Theses defenses are nonspecific because they are not aimed at a specific pathogen.
• Helps prevent disease.
• Helps to slow the progression of the disease.

Question 2

Skin Barrier

Answer 2

Dead skin cells help protect against invasion by microorganisms.
Bacteria that live symbiotically on the skin digest skin oil to produce acids that inhibit many pathogens.

Question 3

Chemical Barriers

Answer 3

• Saliva, tears, and nasal secretions contain the enzyme lysozyme.

Question 4

Lysozyme

Answer 4

breaks down bacterial cell walls, which kills pathogens.

Question 5

Mucus

Answer 5

Acts as a protective barrier, blocking bacteria from sticking to the inner epithelial cells.

Question 6

Nonspecific Response to Invasion.

Answer 6

• The body has nonspecific immune response to pathogens that get beyond its barriers.
• • Cellular defense.
• • Interferon
• • Inflammatory response.

Question 7

Phagocytosis

Answer 7

–Cellular Defense.

Is the process by which phagocytic cells surround and internalize the foreign microorganisms. the phagocytes release digestive enzymes and other harmful chemicals from their lysomes, destroying the microorganism.

Question 8

Interferon

Answer 8

Virus-infected cells secret a protein called interferon.
Binds to neighboring cells and stimulates theses cells to produce antiviral proteins which can prevent viral replication in theses cells.

Question 9

Inflammatory Response

Answer 9

• Increased blood flow to the infected area makes blood vessels more permeable to allow white blood cells to escape into the infected area.

Question 10

Lymphatic System

Answer 10

Specific Immunity

– Organs and cells that filter lymph and blood and destroy foreign microorganisms.

Question 11

Lymphatic Organs

Answer 11

Lymphatic Tissue, includes the lymph nodes, tonsils, spleen, thymus gland, diffused lymphatic tissue found in mucous membranes of the intestinal, respiratory, urinary and genital tracts.

Question 12

Lymphocytes

Answer 12

Are a type of white blood cell that is produced in red bone marrow.

Question 13

Antibodies

Answer 13

Are proteins produced by B lymphocytes that specifically react with a foreign antigen.

Question 14

B lymphocytes (B Cells)

Answer 14

Are located in all lymphatic tissues and can be though of as antibody factories.

The activated helper T cell reproduces, binds, processed antigens, and attaches to a B cell.

The new helper T cells continue the process of binding antigens, attaching to B cells, and reproducing.

Once an activated helper T cell binds to a B cell holding an antigen, the B cell begins to manufacture antibodies that specifically bind to the antigen.

The antibodies can enhance the immune response by binding to microorganisms, making them more susceptible to phagocytosis and by initialing the inflammatory response, helping promote The nonspecific response.

Question 15

T-Cells

Answer 15

Helper T cells bind to and activate cytoxic T cells.
Activated cytotoxic T cells destroy pathogens and release chemicals called cytokines. Cytokines stimulate the cells of the immune system.

Question 16

Passive Immunity

Answer 16

Temporary protection occurs when antibodies are made by other people or animals and are transferred or injected into the body. (mom to baby, pregnancy)

Question 17

Active Immunity

Answer 17

Active immunity occurs after the immune system is exposed to the disease antigens. Immunization is the deliberate exposure of the body to an antigen so a primary response and immune memory cells will develop.

Question 18

Active Immunity (bonus)

Answer 18

• The secondary response to the antigen has a number of different characteristics.
• The response is more rapid than the primary response.
• The overall response, both B and T cell response is greater during the second exposure.
• The overall memory lasts longer after the second exposure.

Question 19

Immune System Failure

Answer 19

Some diseases can affect the immune system effectiveness.
AIDS
HIV infects mainly helper T cells.
The helper T cells become HIV factories, producing new viruses.
The number of helper T cells in an infected person decreases.