Cells, Organs, and Molecules: Anatomy and physiology of the immune system

Question 1

How many RBCs are there per uL of blood

Answer 1

about 5 x 10^6/ uL

Question 2

How many platelets are there per uL of blood?

Answer 2

between 150-400,000/uL

Question 3

The buffy coat is:

Answer 3

WBCs + platelets

Question 4

Leukocytes are nucleated, T or F?

Answer 4

T

Question 5

Which WBCs are mononuclear?

Answer 5

Monocytes and lymphocytes (agranulocytes)

Question 6

Which cells are polymorphonuclear?

Answer 6

granulocytes- Eosinophils, Basophils (related to mast cells), and Neutrophils.

Question 7

Monocytes are immature and becoming mature what?

Answer 7

macrophages or dendritic cells.

Question 8

which type of WBCs have a smooth outlined nucleus?

Answer 8

mononuclear (one nucleus, smooth)

Question 9

Which cells have a nucleus that is lobulated?

Answer 9

Polymorphonuclear cells.

Question 10

what color do polymorphonuclear cells generally stain?

Answer 10

Baso- blue
Neutro- colorless
Eosino- Red

Question 11

Total WBCs per uL of Blood

Answer 11

4500-10500/uL

Question 12

List the WBCs in descending order of prevalence

Answer 12

Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils

No Little Monkeys Eat Bananas

Question 13

Up to 2 years of age what is different about the WBC count?

Answer 13

can have more lymphocytes than Neutrophils

Question 14

Of Lymphocytes how many are T cells and how many are B cells

Answer 14

T- 70%

B- 20%

Question 15

What are central lymphoid organs?

Answer 15

The bone marrow and the thymus.

Question 16

What are peripheral lymphoid organs?

Answer 16

lymph nodes, spleen, Peyer’s patches and mesenteric lymph nodes of the gut, tonsils, and adenoids.

Question 17

Where are most lymphocytes found in the body at any given moment? Blood and lymph, or peripheral lymphoid organs.

Answer 17

In peripheral lymphoid organs,

Question 18

How do central and peripheral organs differ in function?

Answer 18

central- lymphocytes develop here
Peripheral- here mature lymphocytes are organized to trap and respond to foreign invaders, which usually arrive through the body surfaces via lymphatics.

Question 19

In a lymph node what goes through the hilum?

Answer 19

Blood in and out plus efferent lymph

Question 20

what part of blood flow through the lymph node has high cuboidal endothelium?

Answer 20

venules

Question 21

What passes through the lymph node periphery (as opposed to the hilum)?

Answer 21

Afferent lymph (comes in through the periphery, everything else goes through the hilum).

Question 22

The nodes outer region is called the _____ and it is full of tightly packed, highly motile lymphocytes arranged into _____.

Answer 22

cortex, follicles

Question 23

What is a germinal center? What do theses tend to represent?

Answer 23

Frequent, very crowded areas with many dividing cells within a follicle of the cortex (of a lymph node). They represent visible evidence of an immune response.

Question 24

what area of the lymph node is less dense than the cortex but still has huge numbers of dividing lymphocytes?

Answer 24

deep or paracortex.

Question 25

In what regions of a lymph node do B, T, and dendritic cells typically gather (respectively)?

Answer 25

B-cortex (come from bone marrow)
T-paracortex (come from thymus)
Dendritic- in the interface between cortex and paracortex

Question 26

Follicular helper T cells (Tfh) migrate from where to where and do what?

Answer 26

deep cortex into the follicles and help to activate the B cells there.

Question 27

how many lymphocytic circulations are there in the body?

Answer 27

2 blood and lymph

Question 28

in recirculation, a lymphocyte encounters cells lining a _______, in the peripheral lymphoid tissues (especially a lymph node). These cells are ___ and _____ and lymphocytes will bind and pass through these to re-enter the lymph.

Answer 28

postcapillary venule

high and cuboidal

Question 29

lymphocytes circulate between the blood and the lymph. They cross from the blood into the lymph at _____ and from the lymph back into the blood at the ____ via the ____ duct.

Answer 29

lymph nodes
heart
thoracic

Question 30

What is the role of red pulp in the spleen?

Answer 30

similar to medulla in the lymph node- lots of phagocytic cells, can make RBCs if necessary. Makes the body’s most important filter of particulates (bacteria or damaged platelets).

Question 31

the white pulp consists of____.

Answer 31

islands of cells.

Question 32

What kinds of cells are close to the arteriole? farther away?

Answer 32

The sheath of cells which surrounds the central arteriole is made mostly of T cells. the more diffuse cells, farther away, are mostly B cells (similar to lymph node structure).

Question 33

What is a Peyer’s patch?

Answer 33

A GALT or MALT (gut or mucosa associated lymphoid tissue). It underlies the mucosa (especially in the small intestine). There specialized M Cells ingest proteins including viruses and transport them to the location of the Peyer’s patch where B cell follicles and T cell zones are located.

Question 34

What is the difference between an antigen, an immunogen, and a tolerogen?

Answer 34

an antigen is recognized by an antibody, an immunogen is an antigen that triggers an immune response and a tolerogen is an antigen that prevents a immune response to subsequent immunogens containing the same antigenic determinant.

Question 35

The part of an antigen that fits into the receptor is called:

Answer 35

the antigenic determinant or epitope.

Question 36

what 3 conditions must be met to activate the T or B cell?

Answer 36

1. there must be good fit between antigen and receptor
2. several nearby receptors must be simultaneously bound to the antigen
3. Accessory or costimulation surface molecules (of the antibody) must also be involved with the antigen.

Question 37

Once a cell is activated it will differentiate into ____ and _____.

Answer 37

effectors- do the job of killing the foreign particle

memory cells- recirculate efficiently and are easily triggered by a second exposure.

Question 38

A stimulated T cell becomes a _____

Answer 38

T lymphoblast

Question 39

A stimulated B cell becomes a____. This second, larger, differentiated type of cell will go on to become a _____.

Answer 39

B lymphoblast; plasma cell

Question 40

An enormous, specialized cell that makes antibody proteins like nuts. Has a lot of Rough endoplasmic reticulum.

Answer 40

A plasma cell, comes from B lymphoblast.

Question 41

In mammalian embryos, bone marrow function is first found in the _____.

Answer 41

yolk sac and then later in the liver.