Chapter 09 Pharyngeal Apparatus

Chapter 09  Pharyngeal Apparatus

Complete Chapter Questions And Answers
 

Sample Questions

7. ________ Glossopharyngeal nerve
a.
First pharyngeal arch
b.
Second pharyngeal arch
c.
Third pharyngeal arch
d.
Fourth pharyngeal arch
e.
Sixth pharyngeal arch

ANS: C
The glossopharyngeal nerve (CN IX) is the nerve of the third pharyngeal arch; it supplies the stylopharyngeus muscle derived from the muscle element in this arch. Because the dorsal part of the root of the tongue is derived from the third arch, its sensory innervation is partly supplied by the glossopharyngeal nerve.

8. ________ Muscles of facial expression
a.
First pharyngeal arch
b.
Second pharyngeal arch
c.
Third pharyngeal arch
d.
Fourth pharyngeal arch
e.
Sixth pharyngeal arch

ANS: B
The muscles of facial expression are derived from the second pharyngeal arch. Other muscles derived from this arch are the stylohyoid, posterior belly of digastric, and stapedius. From the position of the second arch in the embryo, one would not expect it to give rise to facial muscles. During development, the primordial muscle cells (myoblasts) migrate to the head and retain their original nerve supply from the second arch (i.e., the facial nerve).

9. ________ Supplied by the maxillary division of the fifth cranial nerve
a.
First pharyngeal arch
b.
Second pharyngeal arch
c.
Third pharyngeal arch
d.
Fourth pharyngeal arch
e.
Sixth pharyngeal arch

ANS: A
The maxillary prominence of the first pharyngeal arch is supplied by the maxillary division of the trigeminal nerve (CN V2). The mandibular prominence is supplied by the mandibular branch of this nerve (CN V3). The trigeminal nerve also supplies the muscles of mastication and other muscles derived from this arch. This nerve also supplies the skin over the mandible and the anterior two thirds of the tongue.

10. ________ Stylohyoid ligament
a.
First pharyngeal arch
b.
Second pharyngeal arch
c.
Third pharyngeal arch
d.
Fourth pharyngeal arch
e.
Sixth pharyngeal arch

ANS: B
The stylohyoid ligament is derived from the perichondrium of the second pharyngeal arch cartilage, after it regresses between the styloid process and hyoid bone.