Section 1 After Lecture Questions

Question 1

What are our natural barriers against infection?

Answer 1

Skin, tears, coughing/sneezing, vomiting/diarrhea, etc.

Question 2

How do innate immune cells work?

Answer 2

Phagocytosis and antigen presentation

Question 3

How do innate cells recognize pathogens?

Answer 3

Specific molecules on the pathogen that do not occur on host cells

Question 4

What are the two components of the adaptive immune system?

Answer 4

Humoral and cell-mediated

Question 5

What do the humoral and cell-mediated immune systems do?

Answer 5

Humoral – produce antibodies to fight extracellular infections

Cell-mediated immunity – fight intracellular infections through communication with a damaged host cell

Question 6

Which cells are damaged, that begin the inflammatory process?

Answer 6

Endothelial cells

Question 7

What cell fragments are involved in clotting?

Answer 7

Platelets, which are cytoplasmic fragments of megakaryocytes in bone.

Question 8

What cells cause vasodilation and allow immune cells to exit the blood?

Answer 8

Mast cells; also involved in allergic response (sneeze, watery eyes and nose)

Question 9

What are the first types of innate cells that respond to an infection?

Answer 9

Granulocytes, especially neutrophils – phagocytosis and reactive oxygen killing

Question 10

What cells are phagocytes and antigen presenting cells?

Answer 10

Macrophages (dendritic cells, Kupffer cells, etc)

Question 11

What cells are involved in adaptive immunity?

Answer 11

Lymphocytes

Question 12

What cells are involved in wound healing?

Answer 12

Fibroblasts

Question 13

What does a lymphatic vessel look like?

Answer 13

Thin wall, one-way valves

Question 14

What is lymph composed of?

Answer 14

Water, protein, white blood cells, bacteria, viruses, cancer cells, cell debris

Question 15

What moves the lymphatic fluid and where does it go?

Answer 15

Skeletal muscular contractions; bathes interstitial tissue, back to heart

Question 16

What is the purpose of the lymphatic system?

Answer 16

Clean interstitial tissue, bring infectious/neoplastic debris to secondary lymphoid organ

Question 17

List and describe the functions of the primary lymphoid organs.

Answer 17

Bone marrow – produce immune cells; thymus – mature T lymphocytes

Question 18

What are the secondary lymphoid organs and what do they do?

Answer 18

Lymph nodes, tonsils, spleen, appendix, BALT/GALT/NALT.

They are the sites of the adaptive immune response.

Question 19

What is a follicle? PALS? A germinal center?

Answer 19

• Collection of B cells. T cells lining vessels in spleen. Activated B cells.

Question 20

What are the 3 complement pathways?

Answer 20

Classical, alternate, lectin-binding mannose

Question 21

What initiates each of these pathways?

Answer 21

Classical – Ab binding to microbe; alternate – spontaneous; lectin-binding mannose – L-M.

Question 22

Where do all three pathways converge? What is the end result of complement activation?

Answer 22

C3; MAC

Question 23

What are the main functions of complement?

Answer 23

Cell lysis, opsonization, chemotaxis, inflammation, disposal of waste, regulate immune response.

Question 24

Which by-products induce chemotaxis? Mast cell degranulation? Smooth muscle contraction?

Answer 24

C5a>C3a>C4a are anaphylatoxins – smooth muscle contraction, histamine release, increased vascular permeability, chemoattraction, inflammation.

Question 25

Which by-products induce opsonization?

Answer 25

C3b, C4b

Question 26

What is the name of the group of molecules that helps to regulate complement activation?

Answer 26

Complement control proteins; they act on complement convertases

Question 27

What is the most common complement deficiency and what disease is associated with this? What body parts are most commonly affected?

Answer 27

C1 inhibitor; hereditary angioedema