A
– follicular cells synthesize and secrete thyroglobulin into the follicular lumen; B –
thyroglobulin is an active form of the thyroid hormones; C
– iodination of thyroglobulin
occurs in the colloid near the apical cell surfaces; D
– hormones are liberated from the
storage form by resorption; E
– hormones are released into fenestrated capillaries.
11. Each of the following statements concerning the thyroid parafollicular cells is
true, EXCEPT:
A
– arise from the neural crest; B – occur in the follicular wall or in the interfollicular
spaces; C
– their basal portions rest on the basal lamina; D – their apical portions are in
contact with the colloid; E
– their cytoplasm contains numerous granules with calcitonin.
12. Each of the following statements concerning calcitonin is true, EXCEPT:
A
– is a physiological antagonist to parathyroid; B – lowers the blood calcium level; C –
suppresses bone resorption and increases bone calcification; D
– its secretion is regulated
directly by the blood calcium level; E
– its release is controlled by the pituitary gland.
13. Each of the following statements concerning the adrenal medulla is true,
EXCEPT:
A
– its secretion is modulated by ACTH; B – originates from the neural crest; C – secretes
norepinephrine and epinephrine; D
– its chromaffin cells are modified neurons; E –
contains sinusoidal blood capillaries and large veins.
14. Each of the following statements concerning the adrenal cortex is true, EXCEPT:
A
– secretes steroid hormones; B – consists of epithelial cells; C – arises from the
mesoderm; D
– secretes catecholamines; E – is divided into three zones: glomerulosa,
fasciculata, and reticularis.
15. Each of the following statements concerning the adrenal cortex zona
glomerulosa is true, EXCEPT:
A
– lies beneath the capsule; B – its cells are arranged in the ovoid clusters surrounded by
fenestrated capillaries; C
– its cells secrete mineralocorticoids, primarily aldosterone; D –
is controlled by ACTH; E
– is under feedback control of the renin-angiotensin system.
16. Each of the following statements concerning the adrenal cortex zona fasciculata
is true, EXCEPT:
A
– its cells are arranged in the straight cords; B – contains narrow continuous capillaries;
C
– its cell cytoplasm is rich in lipid droplets containing steroid hormone precursors; D –
secretes glucocorticoids, primarily cortisol; E
– is controlled by ACTH.
Directions
: one or more of the given statements or completions is/are correct. Choose the
answer: A
– if only 1,2, and 3 are correct; B – if only 1 and 3 are correct; C – if only 2 and
4 are correct; D
– if only 4 is correct; E – if all are correct.
17. The following statements regarding the adenohypophysial hormones are true:
(1) are small proteins or glycoproteins (2) are tropic hormones modulating other endocrine
gland activity (3) their secretion is controlled by releasing and inhibitory factors from the
hypothalamus (4) are accumulated in the Herring bodies
18. The following statements regarding the functional significance of the
hypophyseal portal system are true:
(1) hypothalamic regulating factors are released into the primary capillary plexus (2)
hypophyseal portal veins carry these factors to the adenohypophysis (3) releasing factors
leave the blood and enter the adenohypophysis through the secondary capillary plexus (4)
adenohypophysial tropic hormones are released into the secondary capillary plexus
19. The following statements regarding the pars intermedia of the adenohypophysis
are true:
(1) contains acidophils: somatotropes and lactotropes (2) its endocrine cells surround the
colloid-filled cysts (3) hypophyseal portal veins run through it to the pars distalis (4) its
endocrine cells presumably secrete lipotropins and the melanocyte-stimulating hormone
20. The following statements regarding the adenohypophysotropic factors are true: