Exam III

Question 1

What are features of lymph follicles?

Answer 1

Are not enclosed within a capsule

Occur singly or in aggregates

Are sites of B cell localization and proliferation

Question 2

What distinguishes a primary lymph node from a secondary lymph node?

Answer 2

the presence (secondary) or absence (primary) of a germinal center.

Question 3

What are the two components of secondary lymph follicles?

Answer 3

germinal center and corona (cortex)

Question 4

What are CD16 cells also known as?

Answer 4

NK cells

Question 5

CD8+ T cells

Answer 5

recognize peptide fragments of foreign proteins bound to MHC class I on the surface of cells.

Question 6

CD4+

Answer 6

recognize peptide fragments of foreign proteins bound to MHC class II on the surface of cells.

Question 7

What do CD4+ T cells assist in the differentiation of?

Answer 7

CD8+ cells and B cells

Question 8

What do CD8+ cells release?

Answer 8

perforins and fas ligand

Question 9

What molecule stimulates the proliferation of NK cells?

Answer 9

Interleukin-2

Question 10

What is the most important opsonin?

Answer 10

C3B

Question 11

Where are high endothelial venules found?

Answer 11

In lymph nodes

Question 12

What are the functions of high endothelial venules?

Answer 12

They bring blood and lymphocytes from the bone marrow in the lymphnodes.

Question 13

When T cells enter the thymus, what receptors do they initially have?

Answer 13

CD4 and CD8 (they are double positive).

Question 14

here are double positive T cells found in the thymus?

Answer 14

In superifical regions (subcapsule).

Question 15

Where are Hassall’s corpuscles found?

Answer 15

in the thymus

Question 16

What are the results of the complement system?

Answer 16

activation of the membrane attack complex

production of opsonins

Release of chemokines which attract phagocytes to areas of infection or inflammation.

Question 17

What are the cords of Billroth associated with?

Answer 17

the spleen

Question 18

Lymph does not circulate through the thymus. Why is this so?

Answer 18

Because there are no afferent lymphatics in the spleen.

Question 19

What do Hassall’s corpuscles produce, and what is it used for?

Answer 19

thymic stromal lymphopoietin; it is used for stimulation of dendritic cells needed for the maturation of single positive T cells.

Question 20

Where are double negative T cells found?

Answer 20

the subcapsular arear

Question 21

Where are double positive T cells found?

Answer 21

the outer cortex

Question 22

Where are single positive T cells found?

Answer 22

the inner cortex

Question 23

Where does clonal deletion occur?

Answer 23

the medulla

Question 24

What is the purpose of the blood thymus barrier?

Answer 24

to prevent antigens in the blood from reaching developing T cells in the thymus

Question 25

Where are T cells found in the spleen?

Answer 25

surrounding the central artery near the center of the white pulp.

Question 26

Where in the spleen are B cells activated?

Answer 26

marginal zone

Question 27

What happens at the Billroth cords?

Answer 27

macrophages destroy worn-out or defective blood cells.

Question 28

What occurs at the venous sinusoids?

Answer 28

storage sites for healthy red blood cells.

Question 29

What is the flow of the splenic artery?

Answer 29

splenic artery, trabecular artery, central artery

Question 30

What space separates the plates of hepatocytes and the endothelium of sinusoids?

Answer 30

space of disse

Question 31

What is the major duct of the pancreas?

Answer 31

duct of wirsung

Question 32

What do intercalated ducts in the pancreas secrete?

Answer 32

water and bicarbonate ion

Question 33

What do acinar cells in the pancreas secrete?

Answer 33

trypsin, chymotrypsin, amylase and lipase

Question 34

Where are digestive enzymes concentrated and stored in the pancreas?

Answer 34

the golgi

Question 35

What regulates bicarbonate ion secretion?

Answer 35

secretin

Question 36

what do A cells secrete?

Answer 36

glucagon

Question 37

What do B cells secrete?

Answer 37

insulin

Question 38

What is the function of D cells?

Answer 38

to control levels of insulin and glucagon.

Question 39

What two types of cells are present at the islets of langerhan?

Answer 39

A cells (glucagon) and B cells (insulin)

Question 40

What substance acts in response to gastric contents and the pyloric sphincter?

Answer 40

cholecystokinin.

Question 41

What separates the upper two thirds of the tongue from the lower one third?

Answer 41

sulcus termianlis. It is also a taste bud fund in the V shaped landmark of the tongue.

Question 42

What are the type of taste buds (papellae) found at the sulcus terminalis?

Answer 42

circumvallate

Question 43

What is the most numerous of all of the papillae?

Answer 43

filiform papillae

Question 44

What type of epithelium is present at the gut?

Answer 44

simple columnar with goblet cells.

Question 45

What are the four layers of the digestive tube?

Answer 45

mucosa submucosa muscularis externa outermost layer (serosa and adventitia)

Question 46

Where is the myenteric nerve plexus located between?

Answer 46

between two layers of muscle tissue

Question 47

What are the functions of the muscularis externa?

Answer 47

regulates the size of the lumen regulates rhythmic movement of the Gi tract

Question 48

What sympathetics are associated with Meissner's plexus?

Answer 48

parasympathetics

Question 49

What is the function of Meissner's plexus?

Answer 49

regulates local secretions, blood flow and absorption.

Question 50

What is the function of Auerbach's plexus?

Answer 50

coordinates muscular activity of the gut wall

Question 51

In what layer of the digestive tract is Meissner's plexus found?

Answer 51

submucosa

Question 52

What are the walls of the alveoli composed of?

Answer 52

Type I and ii alveolar cells

Question 53

What type of alveolar cells cover the largest surface area?

Answer 53

Type I

Question 54

What is the function of type II alveolar cells?

Answer 54

they serve as stem cells for type I and type II pneumocytes

Question 55

What do goblet cells secrete?

Answer 55

mucous

Question 56

What do neuroendocrine cells release?

Answer 56

catecholamines

Question 57

What pulmonary cells secrete surfactant?

Answer 57

Clara cells and type II alveolar cells.

Question 58

What do type II cells phaocytize?

Answer 58

old surfactant

Question 59

What is the most common type of alveolar cell?

Answer 59

type 1

Question 60

What is the function of clara cells?

Answer 60

to secrete surface active lipoprotein that prevents collapse of terminal bronchioles during exhalation.

Question 61

What are dust cells related to?

Answer 61

congestive heart failure

Question 62

What are the three components of the blood air barrier?

Answer 62

capillary endothelium pneumocyte epithelitum basal lamina of both cell types

Question 63

What are intercalated and principal cells associated with?

Answer 63

the kidney tubules

Question 64

Where does the digestion of sugars begin?

Answer 64

the mouth

Question 65

What epitheliu is characteristic of the gut tract?

Answer 65

simple columnar with goblet cells.