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Free STEP1 Exam Braindumps (page: 4)

Page 4 of 213
PDF with 845 Questions

Clinical edema results when lymphatic vessels are blocked or when the volume of extracellular fluid exceeds the drainage capacity of the lymphatic vessels. Which of the following numbered structures in following figure is a lymphatic vessel?

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5

Answer(s): C

Explanation:

An irregular outline, a thin wall, and the lack of erythrocytes in the lumen characterize lymphatic vessel.
Arterioles (choices A and B) have thicker walls and contain erythrocytes. Venules (choice D) are thin-walled but they contain erythrocytes. Capillaries (choice E) are small in diameter and they contain erythrocytes.



The histological structure marked by the asterisk in Fig. 1-4 is which of the following structures from the integumentary system?

  1. aprocrine sweat gland
  2. dermal papilla
  3. eccrine sweat gland
  4. hair follicle
  5. sebaceous gland

Answer(s): C

Explanation:

This is the secretory portion of the eccrine sweat gland, recognizable by its three cell types. The apical dark cells (arrow 1) are closest to the lumen. The clear or basal cells (arrow 2) and the myoepithelial cells (arrow
3) are located against the basal lamina. Characteristically, these cells are large and the lumen is small. The apocrine sweat gland (choice A) is lined with simple cuboidal epithelium and thus has a large lumen. The dermal papilla (choice B) is formed by fibroblasts, not epithelia. The hair follicle (choice D) is formed by three concentric zones of keratinized cells and does not have a lumen. The sebaceous glands (choice E) are appendages of the hair follicle and their lumen is lined by stratified squamous epithelium.



Occlusion of which of the following vessels affects the entire dorsolateral part of the rostral medulla (level of the restiform body) and produces the lateral medullary (Wallenberg) syndrome?

  1. anterior inferior cerebellar artery
  2. anterior spinal artery
  3. posterior inferior cerebellar artery
  4. posterior spinal artery
  5. superior cerebellar artery

Answer(s): C

Explanation:

The posterior inferior cerebellar artery supplies the rostral, dorsolateral medulla. The posterior spinal (choice D) and anterior spinal (choice B) arteries supply dorsal and ventral portions, respectively, of the caudal medulla. The anterior inferior cerebellar (choice A) and superior cerebellar (choice E) arteries supply portions of the pons and mesencephalon.



The chief or peptic (zymogenic) cells of the gastric glands secrete pepsinogen. The latter is converted to pepsin, a 35-kilodalton (kDa) proteolytic enzyme, when the pH in the stomach falls below 5.0. In Following figure, which of the following arrows point to the location of chief or peptic (zymogenic) cells?

  1. 1
  2. 2
  3. 3
  4. 4
  5. 5

Answer(s): B

Explanation:

Arrow 2 points to the base of the gastric glands where chief or peptic (zymogenic) cells tend to be clustered. Arrow 1 points to the luminal surface of the stomach where mucus-secreting cells are found.
Arrow 3 points to the muscularis mucosae. Arrow 4 points to the middle of the gastric glands where parietal or oxyntic cells tend to be most numerous. Arrow 5 point to the side of a gastric pit where mucus-secreting cells are also found.






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