Overview: Elements of the Immune System

Question 1

Where does hematopoiesis occur in adults vs fetal development?

Answer 1

Adult: bone marrow

Fetus: liver and spleen

Question 2

In what phase of the cell cycle are unactivated T-cells locked?

Answer 2

G1

Question 3

What are the proportions of neutrophils, eosinophils, basophils, monocytes, and lymphocytes in the body?

Answer 3

• Neutrophils: 40-75%
• Eosinophils: 1-6%
• Basophils: <1%
• Monocytes: 2-10%
• Lymphocytes: 20-50%

Question 4

Large reserves of neutrophils are stored in the _____ and are released when needed to fight infection

Answer 4

Bone marrow

Question 5

What happens to neutrophils after they go to the site of infection?

Answer 5

• Phagocytize bacteria
• Neutrophils die in the tissue
• Phagocytized by macrophages

Question 6

On encountering their specific antigen, B cells and T cells differentiate into _____?

Answer 6

Effector cells

Question 7

What are some examples of gut-associated lymphoid tissue (GALT)?

Answer 7

• Tonsils
• Adenoids
• Appendix
• Peyer’s patches

Question 8

_____ are less organized aggregates of secondary lymphoid tissue that line the respiratory epithelium and other mucosal surfaces?

Answer 8

Bronchial-associated lymphoid tissue (BALT)

Question 9

Which white blood cells are directly derived from the common lymphoid precursor?

Answer 9

• B-cells
• NK/T Precursor

Question 10

Which white blood cells are directly derived from the common myeloid precursor?

Answer 10

• Granulocyte-macrophage progenitor
• Megakaryocyte/erythroid progenitor

Question 11

Which white blood cells are directly derived from granulocyte-macrophage progenitors?

Answer 11

• Macrophage and dendritic precursor
• Neutrophils
• Eosinophils
• Basophils
• Unknown precursor that leads to mast cells

Question 12

Which white blood cells are directly derived from the megakaryocyte/erythroid progenitor?

Answer 12

• Megakaryocytes
• Erythroblast

Question 13

What are the two types of small lymphocytes?

Answer 13

1. B cells
2. Cytotoxic and Helper T cells

Question 14

_____ cells are the fully differentiated form of B cells that secrete antibodies

Answer 14

Plasma cells

Question 15

_____ cells kill cells infected with certain viruses

Answer 15

Natural killer cells

Question 16

What is the function of neutrophils?

Answer 16

Phagocytosis and killing of microorganisms

Question 17

Which white blood cells are responsible for controlling immune responses to parasites?

Answer 17

Basophils

Question 18

_____ are white blood cells responsible for killing antibody-coated parasites through release of granule contents

Answer 18

Eosinophils

Question 19

Which white blood cells are responsible for activation of T cells and initiation of adaptive immune responses?

Answer 19

Dendritic cells

Question 20

Which white blood cells are responsible for the expulsion of parasites from the body through release of granules containing histamine and other active agents?

Answer 20

Mast cells

Question 21

_____ cells are the circulating precursors to macrophages

Answer 21

Monocytes

Question 22

What are the functions of macrophages?

Answer 22

1. Phagocytosis and killing of microorganisms
2. Activation of T cells
3. Initiation of immune responses

Question 23

Which white blood cells are responsible for platelet formation and wound repair?

Answer 23

Megakaryocyte