Lecture 16 - Endocrine Microanatomy

Endocrine glands secrete hormones directly into the __________ rather than through ducts.

bloodstream

Because endocrine glands release hormones into circulation, they are typically highly __________.

vascularized

Endocrine glands are considered __________ glands because they lack ducts.

ductless

Hormones are chemical substances produced in the body that regulate the activity of other __________ or __________.

organs; cells

Hormonal responses are usually __________ and __________ compared with nervous system responses.

slow; sustained

Many endocrine pathways function through __________ feedback loops that maintain homeostasis.

negative

In a hormone cascade, one hormone stimulates the release of another hormone in a __________ signaling system.

tiered

The hypothalamus is located in the __________ and integrates the nervous and endocrine systems.

brain

Antidiuretic hormone (ADH) is produced in the __________ nucleus of the hypothalamus.

supraoptic

ADH is also known as __________.

vasopressin

The primary function of ADH is to __________ urine by increasing water reabsorption.

concentrate

Oxytocin is produced in the __________ nucleus of the hypothalamus.

paraventricular

Oxytocin stimulates contraction of __________ smooth muscle during parturition.

uterine

Oxytocin also causes contraction of __________ cells in the mammary gland for milk let-down.

myoepithelial

Hormones produced by the hypothalamus are transported along neuronal __________ to the posterior pituitary.

axons

The pituitary gland is located just __________ the brain within the skull.

below

The pituitary gland is divided into two major portions: the __________ and the __________.

adenohypophysis; neurohypophysis

The anterior pituitary is also called the __________.

adenohypophysis

The posterior pituitary is also called the __________.

neurohypophysis

Chromophobic cells of the pars distalis appear __________ and have an unknown function.

pale / inconspicuous

Chromophilic cells of the pars distalis secrete hormones in response to __________ hormones from the hypothalamus.

releasing

Acidophils have __________ staining cytoplasm and produce growth hormone and prolactin.

eosinophilic

Acidophils produce __________ hormone and __________ hormone.

growth; prolactin

Basophils have more __________ staining cytoplasm compared with acidophils.

basophilic

Basophils produce __________, __________, __________, and __________.

ACTH; TSH; FSH; LH

The pars intermedia contains __________ cells that may form follicles.

basophilic

The pars intermedia produces __________ stimulating hormone.

melanocyte

The posterior pituitary consists primarily of __________ tissue.

nervous

The posterior pituitary contains unmyelinated __________ originating from the hypothalamus.

axons

The supporting glial cells of the posterior pituitary are called __________.

pituicytes

The posterior pituitary releases __________ and __________.

oxytocin; ADH

These hormones are produced in the __________ but released from the posterior pituitary.

hypothalamus

The adrenal gland is composed of the adrenal __________ and adrenal __________.

cortex; medulla

The adrenal cortex consists of __________ distinct zones.

three

The zona glomerulosa lies just beneath the __________ of the adrenal gland.

capsule

Cells in this region form __________ clusters or arches.

glomeruloid

The zona glomerulosa produces __________ hormones.

mineralocorticoid

The main hormone produced by the zona glomerulus is __________.

aldosterone

Aldosterone primarily regulates __________ balance.

salt / sodium

The zona fasciculata is the __________ layer of the adrenal cortex.

middle

Cells of the zona fasciculata often have __________ cytoplasm due to lipid content.

foamy

These cells are sometimes called __________.

spongiocytes

The zona fasciculata produces __________ hormones.

glucocorticoid

The major hormone produced in zona fasciculata is __________.

cortisol

Cortisol plays an important role in __________ metabolism.

glucose

The zona reticularis consists of __________ cords of cells.

anastomosing

The zone reticularis produces __________ hormones.

sex

One hormone produced by the zona reticularis is __________.

testosterone

The adrenal medulla produces hormones called __________.

catecholamines

The two primary catecholamines produced are __________ and __________.

epinephrine; norepinephrine

These hormones are responsible for the __________ response to stress.

fight-or-flight

The thyroid gland contains spherical structures called __________.

follicles

These follicles are lined by __________ epithelial cells.

cuboidal to columnar

The center of thyroid follicles contains __________, which stores hormone precursors.

colloid

Thyroid follicular cells produce the hormones __________ and __________.

T3; T4

These hormones primarily regulate __________ rate.

metabolic

C cells are located in the __________ between thyroid follicles.

interstitium

C cells produce the hormone __________.

calcitonin

Calcitonin functions to __________ blood calcium levels.

decrease

Most animals have __________ parathyroid glands.

four

Parathyroid glands contain clusters or cords of __________ cells.

chief

The primary hormone produced by chief cells is __________ hormone.

parathyroid

Parathyroid hormone functions to __________ blood calcium levels.

increase

The pineal gland is located __________ within the brain.

deep

The pineal gland functions as a __________ clock that regulates circadian rhythms.

biological

The pineal gland produces the hormones __________ and __________.

serotonin; melatonin

Melatonin plays an important role in regulating __________ cycles.

sleep

The __________ and __________ bodies monitor blood oxygen, carbon dioxide, and pH.

carotid; aortic

These organs help regulate __________ in response to blood chemistry changes.

respiration

The endocrine portion of the pancreas consists of the __________ of Langerhans.

islets

The exocrine pancreas produces digestive __________.

enzymes

Islets of Langerhans appear as __________ staining clusters of cells within pancreatic tissue.

pale

Alpha cells produce the hormone __________.

glucagon

Glucagon functions to __________ blood glucose levels.

increase

Beta cells produce the hormone __________.

insulin

Insulin functions to __________ blood glucose levels.

decrease

Delta cells produce the hormone __________.

somatostatin

Somatostatin inhibits secretion of __________ and __________.

glucagon; insulin

With routine light microscopy, the different pancreatic islet cell types __________ be distinguished.

cannot