Unit 2-Lesson 1 The immune system

Question 1

What is the immune system?

Answer 1

The body’s defense against disease-causing organisms, malfunctioning cells, and foreign particles.

Question 2

What role does the lymphatic system play in the immune system?

Answer 2

It helps remove toxins from the body, destroys pathogens, and filters waste.

Question 3

What is immunity?

Answer 3

The condition of being resistant to pathogens and the diseases they cause.

Question 4

What are pathogens?

Answer 4

Harmful microorganisms that could cause disease.

Question 5

What is nonspecific (innate) immunity?

Answer 5

Protects the body against everyday foreign invaders through general mechanisms.

Question 6

Give an example of nonspecific immunity.

Answer 6

• Skin forming a barrier
• Hairs in lungs filtering bacteria
• Stomach acid breaking down food and pathogens

Question 7

What is specific (adaptive) immunity?

Answer 7

Targets and attacks a specific foreign agent or pathogen.

Question 8

Name a structure in the immune system.

Answer 8

• Tonsils
• Thymus
• Lymph Nodes
• Spleen
• Appendix
• Peyer’s Patch
• Bone Marrow

Question 9

What do lymph nodes contain?

Answer 9

Reticular tissue filled with lymphocytes and macrophages.

Question 10

What is the major function of the lymphatic system?

Answer 10

To pick up extra tissue fluid (lymph), filter it, and return it to the bloodstream.

Question 11

How does lymph circulate throughout the lymphatic system?

Answer 11

Moves via a one-way system with contraction of skeletal and smooth muscles.

Question 12

What happens when there is obstruction in the lymphatic system?

Answer 12

It leads to edema, which is the accumulation of fluid in the tissues.

Question 13

What are the three types of defenses in the immune system?

Answer 13

• First Line of Defense: Non-specific Immunity
• Second Line of Defense: Non-specific Immunity
• Third Line of Defense: Immune Specific or Adaptive Response

Question 14

What are mechanical barriers in the first line of defense?

Answer 14

• Skin
• Mucous membranes
• Cilia hairs

Question 15

What are chemical barriers in the first line of defense?

Answer 15

• Sweat
• Mucus
• Tears
• Saliva
• Stomach acid

Question 16

What role do resident microorganisms play in immunity?

Answer 16

Normal flora that help prevent the growth of harmful pathogens.

Question 17

What are the components of the second line of defense?

Answer 17

• Immune cells (e.g., Basophils, Phagocytes)
• Proteins
• Inflammation
• Fever

Question 18

What triggers the inflammatory response?

Answer 18

Cytokines and histamines released when tissues are damaged or attacked.

Question 19

What is phagocytosis?

Answer 19

The process by which phagocytes engulf and digest foreign cells.

Question 20

What happens during a fever?

Answer 20

Core body temperature increases to kill pathogens and enhance cell metabolism.

Question 21

What is the maximum temperature for a fever to avoid damaging host cells?

Answer 21

40 degrees Celsius.

Question 22

What are antigens?

Answer 22

Surface markers on all cells that the body recognizes as self or non-self.

Question 23

What is the role of Helper T-cells in the specific immune response?

Answer 23

Recognize pathogens and activate B-cells and Cytotoxic T-cells.

Question 24

What do plasma cells produce?

Answer 24

Antibodies that deactivate pathogens.

Question 25

What is the function of memory B-cells and memory T-cells?

Answer 25

Remain in the body to speed up the immune response if the same antigen reappears.

Question 26

True or False: Suppressor T-cells stop the immune response when all foreign antigens have been destroyed.

Answer 26

True.

Question 27

Fill in the blank: The first line of defense includes _______ barriers.

Answer 27

physical, chemical, and mechanical.

Question 28

What are the two types of immunity?

Answer 28

* Cellular Immunity * Antibody or Humoral Immunity

Question 29

What do lymphocytes detect?

Answer 29

Presence of foreign antigens ## Footnote Lymphocytes are essential for identifying threats to the immune system.

Question 30

What specific proteins do lymphocytes produce?

Answer 30

Antibodies ## Footnote Antibodies play a crucial role in the immune response.

Question 31

How does an antibody operate?

Answer 31

Deactivation of a bacterium by an antibody ## Footnote Antibodies neutralize pathogens and mark them for destruction.

Question 32

What is the first line of defense in the immune system?

Answer 32

Non-specific Immunity ## Footnote This includes physical, chemical, and mechanical barriers.

Question 33

What role do Basophils play in the immune system?

Answer 33

Release Histamine ## Footnote Histamine is involved in inflammatory responses.

Question 34

What do Phagocytes do?

Answer 34

Engulf pathogens ## Footnote Phagocytes are essential for clearing infections.

Question 35

What type of cells patrol the lymph and blood looking for abnormal cells?

Answer 35

Natural killer cells ## Footnote They can destroy infected or cancerous cells.

Question 36

What is inflammation caused by?

Answer 36

Histamine ## Footnote Inflammation is characterized by redness, warmth, swelling, pain, and discharge.

Question 37

What does fever do in the immune response?

Answer 37

Triggers an increase in body temperature ## Footnote This helps kill pathogens and reduces iron levels to inhibit reproduction.

Question 38

What is the third line of defense in the immune system?

Answer 38

Specific Immunity ## Footnote This targets specific pathogens for a tailored immune response.

Question 39

What do T-lymphocytes initiate?

Answer 39

Cell-mediated immunity ## Footnote T-lymphocytes are crucial for fighting infections at the cellular level.

Question 40

What do B-lymphocytes initiate?

Answer 40

Antibody immunity ## Footnote B-lymphocytes are responsible for producing antibodies.

Question 41

What is acquired immunity?

Answer 41

A state of immunity developed after exposure to specific antigens ## Footnote This allows for quicker response upon re-exposure.

Question 42

What are the three types of acquired immunity?

Answer 42

* Naturally Occurring Immunity (NAI) * Artificially Acquired Immunity (AAI) * Passively Acquired Immunity (PAI) ## Footnote Each type has different mechanisms of protection.

Question 43

What is Naturally Occurring Immunity (NAI)?

Answer 43

Occurs when the body is exposed to infectious agents ## Footnote This can happen through infections.

Question 44

What is Artificially Acquired Immunity (AAI)?

Answer 44

Occurs when the body is exposed to weakened or killed infectious agents through vaccination ## Footnote Vaccines help prepare the immune system for future infections.

Question 45

What is Passively Acquired Immunity (PAI)?

Answer 45

Results when antibodies are introduced into the body ## Footnote This can occur through breastfeeding or antibody treatments.

Question 46

What do antibiotics do?

Answer 46

Kill or inhibit the growth of microorganisms ## Footnote Antibiotics target bacteria specifically.

Question 47

What is the function of Penicillin?

Answer 47

Inhibits cell wall synthesis in bacteria ## Footnote This mechanism damages bacterial cells without harming human cells.

Question 48

What is the most common antibody in the blood?

Answer 48

IgG ## Footnote IgG can cross the placental membrane and provides passive immunity to the fetus.

Question 49

What does IgM do?

Answer 49

Reacts with certain antigens, usually on first exposure ## Footnote IgM is often the first antibody produced in response to an infection.

Question 50

What is the role of IgA?

Answer 50

Protects mucosal surfaces from attachment of pathogens ## Footnote Found in secretions like saliva and tears.

Question 51

What is the function of IgE?

Answer 51

Involved in allergic reactions ## Footnote IgE binds to mast cells, which release inflammatory substances.

Question 52

Where is IgD typically found?

Answer 52

On B cells ## Footnote IgD may be involved in B cell activation but is not released into the bloodstream.