Chapter 17 - Endocrine Glands Flashcards
What is the function of the endocrine system?
Responsible for maintaining homeostasis via prescise regulation.
What does the hypothalumus do in the endocrine system?
Regulates the pituitary glands activities through the production of neurohormones.
What is the function of the pituitary gland?
Regulates many body functions and other endocrine glands.
Where is the pituitary gland located?
Beneath the hypothalumus of the brain in the skull bone indentation called Stella Turcica which forms a nest to protect the gland.
What are the two areas of the pituitary gland?
Posterior Pituitary: Extention of the hypothalumus, produces neurohormones.
Anterior Pituitary: Produces endocrine hormones. Contains glandular tissue.
What are the two parts of the Posterior Pituitary?
Infundibulum
Pars Nervosa
What are the three parts of the Anterior Pituitary?
Pars Tuberalis
Pars Intermedia
Pars Distalis
What is the name of the structure that connects the Hypothalumus and the Posterior Pituitaty? How does it function?
Hypothalamo-Hypophysial Tract
Nerve cells are produced by the hypothalumus, they are sent through the posterior pituitary via the HHT and then they are released into the bloodstream.
What hormones are produced by the Posterior Pituitary?
Antidiuretic Hormone (ADH) - Prevents the output of large amounts of urine.
Oxytocin: Stimulates smooth muscle fibers in the uterus for childbirth and promotes ejection of milk during lactation.
What is the name of the structure that connects the hypothalumus to the anterior pituitary gland? How does it function?
Hypothalamo-hypophysial Portal System
Neurohormones are produced by Hypothalumus and decend through portal system. They enter anterior pituitary and leave the capillaries and enter the endocrine glands and tell them to produce certain hormones.
What are the 5 releasing neurohormones produced by the Hypothalumus and cause the anterior pituitary to release specific hormones?
GHRH- Growth hormone-releasing hormone
TRH - Thyrotropic-releasing hormone
CRH - Corticotropin-releasing hormone
GnRH - Gonadotropin-releasing hormone
PRH - Prolactin-releasing hormone
What are the 2 inhibiting neurohormones produced by the HT that inhibit the anterior pituitary gland from producing a specific hormone?
GHIH - Growth hormone-inhibiting hormone
PIH - Prolactin-inhibiting hormone
What is the function of the Growth Hormone?
Promotes bone and cartiledge growth.
Stimulates breakdown of fat to be used as energy.
What is the function of TSH - the thyroid hormone?
Causes the production of T3 an T4
What is the function of ACTH, the hormone released by CRH?
This hormone causes cortisol and aldosterone secretion from the adrenal cortex and also causes increase in production of melanin.
What is the function of MSH and endorphins?
MSH causes melanocytes to produce more melanin. Endorphins act as a pain killer during times of stress.
What are the functions of Gonadotropins, LH, FSH, and prolactin?
Gonadotropins promote the growth and function of the gonads.
LH and FSH: regulate the production of reproductive hormones.
Prolactin: Role in milk production
Describe the anatomy of the thyroid gland.
Consists of two lobes that are connected by the isthmus. It is highly vascular and the only gland that stores hormones.
What is the cell composition of the thyroid gland?
Composed of follicles filled with thyroglobulin. These are surrounded by a single layer of follicular cells.