Histology Testbank: Endocrine 1a

Instructions: For each histology question, pick the one best answer. This histology test bank is also useful for the histology questions on the USMLE (USMLE step 1).

1.
Which of the following is NOT a characteristic of the endocrine system?
a. Products secreted into blood
b. Glands with ducts
c. Secretes hormones
d. Non localized response
e. All of the following are characteristics of the endocrine system

Answer: b

The endocrine system is a system of cellular communication. The means of communication is via hormones. The hormones are secreted by ductless glands directly into the bloodstream. Generally, the response to hormones is non localized.

If a gland secretes its product through a duct, it is an exocrine gland.

2.
What type of hormone is testosterone?
a. Protein
b. Amino acid chain
c. Steroid
d. Catecholamine
e. None of the above

Answer: c

Hormones can have a variety of structures. Hormones which are proteins include insulin and prolactin. Peptide chains are short chains of amino acids. Examples of hormones which are peptide chains are antidiuretic hormone and oxytocin. Steroid hormones are cholesterol derivatives. Steroid hormones include testosterone and estradiol. Norepinephrine and epinephrine are catecholamines.

3.
What organ is nicknamed the "master gland"
a. Adrenal medulla
b. Adrenal cortex
c. Brain
d. Pituitary
e. Heart

Answer: d

The pituitary is nicknamed the master gland.

4.
What cell type secretes ACTH?
a. Lactotropic cells
b. Thyrotropic cells
c. Somatotropic cells
d. Corticotropic cells
e. Gonadotropic cells

Answer: d

There are several cell types in the pars distalis (anterior pituitary). Lactotropic cells secrete prolactin. Thyrotropic cells secrete thyroid stimulating hormone (TSH). Somatotropic cells secrete growth hormone. Corticotropic cells secrete adrenocorticotropic hormone (ACTH) and melanocyte-stimulating hormone (MSH). Gonadotropic cells secrete follicle stimulating hormone (FSH) and luteinizing hormone (LH).

5.
Where is corpora arenacea found?
a. Pituitary
b. Pineal gland
c. Adrenal gland
d. Pancreas
e. Thyroid

Answer: b

Corpora arenacea is nicknamed "brain sand". Corpora arenacea is calcification seen in the pineal gland.

6.
Which gland secretes melatonin?
a. Pancreas
b. Thyroid
c. Pineal gland
d. Adrenal gland (cortex)
e. Adrenal gland (medulla)

Answer: c

The endocrine portion of the pancreas secretes insulin, glucagon, and somatostatin. The thyroid gland secretes the thyroid hormones (T3 and T4) and calcitonin. The pineal gland secretes melatonin. The cortex of the adrenal gland secretes a variety of corticosteroids. It secretes mineralocorticoids (such as aldosterone), glucocorticoids (such as cortisol) and sex steroids. Epinephrine and norepinephrine are secreted from the adrenal medulla.

7.
Which cell type are involved in the secretion thyroglobulin?
a. Principal cell
b. Oxyphil cell
c. Parafollicular cells
d. Follicular cells
e. Chromaffin cells

Answer: d

There are two cell types in the parathyroid gland: principal cells and oxyphil cells. Principal cells are also called chief cells. Principal cells are the more prevalent. Oxyphil cells are also found in the parathyroid gland; however they are not as prevalent as principal cells.

There are two cell types in the thyroid: follicular cells and parafollicular cells. Follicular cells release and store thyroid hormone. Parafollicular cells of the thyroid gland are also called C cells. They secrete calcitonin.

The cells of the adrenal medulla are chromaffin cells.

8.
Where is insulin secreted from?
a. Alpha cells
b. Beta cells
c. Gamma cells
d. Delta cells
e. Acini

Answer: b

The pancreas is both an endocrine and exocrine organ.

The endocrine portion of the pancreas is housed in the islets of Langerhans. Within the islets, there are several cell types. The alpha cells secrete glucagon. The beta cells secrete insulin. The delta cells secrete somatostatin. The gamma cells secrete pancreatic polypeptide.

The acini is the exocrine portion of the pancreas.

9.
Which of the following is part of the adrenal gland?
a. Chromaffin cells
b. Zona reticularis
c. Zona glomerulosa
d. Zona fasciculata
e. All of the above

Answer: e

The adrenal gland is composed of the adrenal cortex and the adrenal medulla.

The layers of the adrenal cortex, from outermost to innermost are: zona glomerulosa, zona fasciculata, and zona reticularis. The respective principle products are: mineralocorticods, glucocorticoids, and sex steroids.

The cells of the adrenal medulla are chromaffin cells. They secrete the catecholamines (epinephrine and norepinephrine).

Histology hint from Sarah Bellham: A mnemonic to remember the layers of the adrenal cortex and their respective products is "Go Find Rex; Make Good Sex" (glomerulosa, fasciculata, reticularis) (mineralocorticoid, glucocorticoid, sex steroids).

10.
Which part the adrenal gland secretes glucocorticoids?
a. Chromaffin cells
b. Zona reticularis
c. Zona glomerulosa
d. Zona fasciculata
e. None of the above

Answer: d

The adrenal gland is composed of the adrenal cortex and the adrenal medulla.

The layers of the adrenal cortex, from outermost to innermost are: zona glomerulosa, zona fasciculata, and zona reticularis. The respective principle products are: mineralocorticods, glucocorticoids, and sex steroids.

The cells of the adrenal medulla are chromaffin cells. They secrete the catecholamines (epinephrine and norepinephrine).

Histology hint from Sarah Bellham: A mnemonic to remember the layers of the adrenal cortex and their respective products is "Go Find Rex; Make Good Sex" (glomerulosa, fasciculata, reticularis) (mineralocorticoid, glucocorticoid, sex steroids).