641. The structures which are not seen in a decalcified section are:
A.Dentinal tubules.
B.Incremental lines of Retzius.
C.Secondary dentin.
D.Cellular cementum.

642. Interglobular spaces:
A. Do not contain dentinal tubules.
B. Do not contain type I collagen.
C. Are formed during the course of globular mineralization.
D. Are seen only in secondary dentin.

643. Which would not be present in a ground section?
A. Inorganic crystals.
B.Odontoblast.
C.Interglobular space.
D. Dentinal tubules.

644. A major difference between secondary and primary dentine is that:
A. There is no predentine.
B. There is no hydroxyapatite.
C. There is no collagen fibers.
D. The dentinal tubules pass in wavier course through secondary dentine.

645. The interglobular dentin is found:.
A. Near the amelo-cemental junction.
B. In the root dentin.
C. Near the amelo-dentinal junction.
D. Near the dentino-cemental junction.

646. Which of the following is MOST likely to be found in the dentinal tubules:
A. Tomes’ fibers.
B.Oxytalan fibers.
C. Tomes’ process.
D. Thick collagen fibers.

647. Primary dentin differs from both secondary and reparative dentin in that:
A. Its matrix is calcified.
B. Its inorganic component is hydroxyapatite.
C. It usually has a greater number of tubules per unit area.
D. It is produced by mesenchymal cells.

648. Which of the following is not present within dentin?
A.Cell bodies.
B.Hydroxyapatite.
C.Collagen type I.
D. Incremental lines.

649. Which of the following is true of peritubular dentin ?It :
A. Is less mineralized than intertubular dentin.
B. May be considered as intratubular dentin.
C. Is best visualized in decalcified sections.
D. Is found in the interglobular dentin.

650. Which of the following is not present in odontoblasts?
A. Golgi saccules and vesicles.
B. Rough endoplasmic reticulum.
C. Desmosome-like junctions.
D.Numerous processes forming a striated border.

NOTE
IF YOU THINK ANY OF THE MCQ ABOVE IS WRONG.
PLEASE COMMENT WITH CORRECT ANSWER AND ITS DETAIL EXPLANATION IN COMMENT BOX.
THANK YOU