Immune System

Question 1

What are the two main types of immunity in the immune system?

Answer 1

Non-specific (innate) immunity and adaptive (specific) immunity

Non-specific immunity is the first line of defense against pathogens, while adaptive immunity develops over time.

Question 2

What is the first line of defense against pathogens?

Answer 2

Mechanical barriers such as the skin and mucous membranes

These barriers prevent pathogens from entering the body.

Question 3

Name some chemical barriers involved in the immune response.

Answer 3

• Low pH of gastric juice
• Interferons
• Antimicrobial proteins such as defensins
• Complement proteins

These chemicals help to inhibit pathogen growth.

Question 4

What role do phagocytes play in the immune system?

Answer 4

They engulf pathogens

Phagocytes are key components of the innate immune response.

Question 5

What is the function of natural killer cells?

Answer 5

They destroy infected cells

Natural killer cells are part of the non-specific immune response.

Question 6

How does inflammation contribute to immunity?

Answer 6

It offers nonspecific protection

Inflammation helps to isolate and eliminate pathogens.

Question 7

What triggers an adaptive immune response?

Answer 7

An antigen

An antigen is a toxin or molecule on the surface of a pathogen that the immune system recognizes as foreign.

Question 8

What is the role of lymphocytes in adaptive immunity?

Answer 8

They produce antibodies, kill infected cells, or direct other immune responses

Lymphocytes are crucial for the adaptive immune response.

Question 9

What are the two main types of lymphocytes involved in adaptive immune responses?

Answer 9

T-lymphocytes (T cells) and B-lymphocytes (B cells)

Both types of lymphocytes play distinct roles in the immune response.

Question 10

Where do T cells mature?

Answer 10

Thymus

Question 11

What type of immunity are T cells involved in?

Answer 11

Cell-mediated immunity

Question 12

What is the role of cytotoxic T cells?

Answer 12

Kill infected or abnormal cells

Question 13

What do helper T cells secrete?

Answer 13

Cytokines

Question 14

What is the function of regulatory (suppressor) T cells?

Answer 14

Inhibit T and B cells to stop the immune response

Question 15

Where do B cells mature?

Answer 15

Bone marrow

Question 16

What type of immunity are B cells involved in?

Answer 16

Humoral-mediated immunity

Question 17

What is required for the initial activation of B cells?

Answer 17

Encountering freely circulating antigens and possibly co-stimulation by helper T cells

Question 18

What do plasma cells produce?

Answer 18

Antibodies

Question 19

What do memory B cells do during a subsequent infection?

Answer 19

Produce antibodies

Question 20

What type of cells are neutrophils?

Answer 20

Phagocytes

Question 21

What is the primary function of eosinophils?

Answer 21

Regulate inflammatory responses and kill foreign invaders, often parasitic worms

Question 22

What do mast cells and basophils release?

Answer 22

Histamine and heparin

Question 23

What are macrophages derived from?

Answer 23

Monocytes

Question 24

What is the function of dendritic cells?

Answer 24

Activate naive T cells

Question 25

How do natural killer cells destroy infected cells?

Answer 25

By binding and releasing granzymes that trigger apoptosis

Question 26

What is the function of bone marrow in the immune system?

Answer 26

Produces hematopoietic stem cells and is the site of B cell differentiation

Question 27

What is the role of the thymus in the immune system?

Answer 27

Site of T cell differentiation

Question 28

What does the spleen filter from the blood?

Answer 28

Aged blood cells, pathogens, and debris

Question 29

What is found in the white pulp of the spleen?

Answer 29

B and T cells

Question 30

What do lymph nodes provide for lymphocytes?

Answer 30

A place to proliferate and filter lymph

Question 31

Where are clusters of lymphatic cells found in the body?

Answer 31

Tonsils, appendix, and Peyer's patches of the small intestine

Question 32

Fill in the blank: T cells, B cells, and macrophages provide protection against _______.

Answer 32

Pathogens

Question 33

What are lymphocytes?

Answer 33

Specialized white blood cells that destroy disease-causing microorganisms.

Question 34

What is an antigen?

Answer 34

A substance that elicits a response from the immune system.

Question 35

What are common types of antigens?

Answer 35

* Viruses * Bacteria * Fungi * Pollen grains

Question 36

What are self-antigens?

Answer 36

Antigens produced by the body that rarely initiate an immune response.

Question 37

What are antibodies also known as?

Answer 37

Immunoglobulins.

Question 38

How do antibodies function in the immune response?

Answer 38

They bind to specific antigens and can disarm pathogens in various ways.

Question 39

What is opsonization?

Answer 39

A process that enhances phagocytosis.

Question 40

What role do lymphatic capillaries play in fluid balance?

Answer 40

They collect excess interstitial fluid and return it to the bloodstream.

Question 41

What is lymph?

Answer 41

Excess interstitial fluid collected by lymphatic capillaries.

Question 42

What are chylomicrons?

Answer 42

Fats transported in lymph that give it a whitish appearance.

Question 43

Fill in the blank: Antibodies can _______ pathogens by blocking their ability to attach to cells.

Answer 43

neutralize

Question 44

What is the function of the thoracic duct?

Answer 44

Drains lymph into the left subclavian vein.

Question 45

What is the role of the right lymphatic duct?

Answer 45

Drains lymph into the right subclavian vein.

Question 46

What is the primary function of the immune system regarding fluid distribution?

Answer 46

Equalization of fluid between the blood and tissues.

Question 47

What can activate the complement system?

Answer 47

Binding of antibodies to antigens.

Question 48

What can cause inflammation in the immune response?

Answer 48

Antibodies promoting inflammation.

Question 49

What are the primary lymphatic organs involved in lymphocyte production?

Answer 49

Bone marrow and thymus ## Footnote These organs are crucial for the production and differentiation of lymphocytes.

Question 50

What type of stem cells in the red bone marrow give rise to immature lymphocytes?

Answer 50

Hemocytoblasts ## Footnote Hemocytoblasts are the progenitor cells that develop into various blood cells, including lymphocytes.

Question 51

What do lymphocytes that remain in the bone marrow differentiate into?

Answer 51

B cells and natural killer (NK) cells ## Footnote These cells play important roles in the immune response.

Question 52

Where do immature lymphocytes migrate to differentiate into T cells?

Answer 52

Thymus ## Footnote The thymus is essential for the maturation of T cells, a type of lymphocyte.

Question 53

What are the secondary lymphatic organs where lymphocytes migrate?

Answer 53

Lymph nodes, spleen, and tonsils ## Footnote These organs play critical roles in filtering lymph and housing immune cells.

Question 54

What happens to lymphocytes when they make contact with antigens?

Answer 54

They are activated and mature into effector cells ## Footnote Effector cells are responsible for carrying out immune responses.