28

146. In the keyhole concept for the shape of the cross-section of enamel rods
 

a. the crystallites in the head lie parallel to the surface of the enamel
b. the tails are directed mesially
c. the heads are directed mesially
d. the tails are directed incisally
e. the heads are directed incisally

147. The epithelial (Hertwig's) root sheath is involved in the formation of
 

a. enamel
b. crown
c. root
d. coronal pulp chamber
e. epithelial pearls

 
148. Mucous secreting cells are least appropriately described as having
 

a. lighter stained cytoplasm than serous cells
b. flattened nuclei
c. relatively vacant appearing cytoplasm
d. distinct cell boundaries
e. the ability to form demilunes

 
149. Which one of the following glands would possess numerous demilunes?
 

a. parotid
b. palatine
c. posterior lingual
d. von Ebner
e. sublingual

 
150. Sharpey's fibers are generally oriented in cementum
 

a. parallel to collagenic fibers produced by cementoblasts
b. randomly
c. parallel to the surface of cementum
d. perpendicular to the dentinocemental junction
e. either b or c