Free STEP1 Exam Braindumps (page: 30)

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An opera singer, who has maintained a demanding work schedule, worries about the effect on her vocal cords. The epithelium covering the vocal cords is which of the following?

  1. pseudostratified ciliated
  2. simple columnar
  3. simple cuboidal
  4. simple squamous
  5. stratified squamous

Answer(s): E

Explanation:

A stratified squamous epithelium covers the vocal cords or folds. This epithelium protects the underlying tissue from the mechanical stress acting on the surface of the vocal cords. A simple squamous epithelium (choice D) is not suitable for protection. The rest of the larynx is covered with a pseudostratified ciliated epithelium (ie, a respiratory epithelium [choice A]). Simple columnar (choice B) and simple cuboidal (choice C) epithelia are found more commonly in organs with secretory or absorptive functions.



A patient suffers from Frey's syndrome manifested by perspiration of the skin covering the left parotid gland whenever the patient eats. On inquiry, the patient reveals that he suffered deep injuries on that side of his face and neck in an automobile accident. You explain to him that his syndrome results from abnormal connections between the great auricular nerve and parasympathetic secretomotor fibers, which normally innervate only the parotid gland. This abnormal reinnervation occurred during the healing period after the accident. The parasympathetic secretomotor fibers to the parotid gland are carried by which of the following?

  1. auriculotemporal nerve
  2. buccal branch of the facial nerve
  3. buccal nerve
  4. greater petrosal nerve
  5. lesser petrosal nerve

Answer(s): A

Explanation:

The auriculotemporal nerve is a branch of the mandibular division of the trigeminal nerve. It carries postganglionic parasympathetic fibers from the otic ganglion to the parotid gland. The buccal nerve (choice C) is a sensory branch of the mandibular division of the trigeminal nerve. It innervates the gingival adjacent to the two posterior molar teeth, the mucosa, and skin of the cheek. The buccal branch of the facial nerve (choice B) provides motor innervation to the muscles around the mouth. The greater petrosal nerve (choice D) is a branch of the facial nerve from the geniculate ganglion. It carries preganglionic parasympathetic fibers to the pterygopalatine ganglion. The lesser petrosal nerve (choice E) is a continuation of the tympanic branch of the glossopharyngeal nerve and carries preganglionic parasympathetic fibers to the otic ganglion.



Your young female patient has a large bulge on the anterior thigh below the inguinal ligament. You suspect an abdominal hernia that has passed through the femoral ring into the femoral sheath and then through the saphenous hiatus into the subcutaneous layer of the upper thigh. In addition to the hernia sac, you would expect the femoral canal to contain which of the following?

  1. connective tissue and lymph nodes
  2. femoral artery
  3. femoral nerve
  4. femoral vein
  5. great saphenous vein

Answer(s): A

Explanation:

The femoral canal, the medial compartment of the femoral sheath, contains only a slight amount of loose connective tissue and one or two lymphatic vessels and nodes. The femoral artery (choice B) is found in the lateral compartment of the femoral sheath with the genital branch of the genitofemoral nerve. The femoral nerve (choice C) is the most lateral structure in the femoral triangle, but it does not lie within the femoral sheath. The femoral vein (choice D) occupies the intermediate compartment of the femoral sheath.
The saphenous vein (choice E) is a superficial vein that passes through the saphenous hiatus to end in the femoral vein. It does not lie within the femoral canal.



Sensations from the thoracic and abdominal organs are usually difficult to localize. They are conveyed by general visceral afferent (GVA) fibers, which synapse in which of the following nuclei?

  1. ambiguus nucleus
  2. dorsal motor nucleus of the vagus
  3. hypoglossal nucleus
  4. solitary nucleus
  5. spinal (descending) trigeminal nucleus

Answer(s): D

Explanation:

GVA fibers from the thoracic and abdominal organs have their perikarya in the inferior vagal (nodose) ganglion and project to the solitary nucleus. The ambiguus nucleus (choice A) provides branchial efferent (motor) fibers to the stylopharyngeus, soft palate, pharyngeal, and laryngeal muscles. The dorsal motor nucleus of the vagus (choice B) sends parasympathetic preganglionic fibers to the thoracic and abdominal viscera. The hypoglossal nucleus (choice C) provides motor innervation for the muscles of the tongue. The spinal (descending) trigeminal nucleus (choice E) receives pain and temperature fibers from the face area.






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