The Endocrine System

Michael McKennaLou MaselliBrendan Quinn

May 2014

What is it?

Includes all of the glands of the body

Glands produce hormones

Helps stabilize the body; homeostasis, cellular metabolism, sexual development, digestion, and heart rate

Pituitary Gland“Master Gland”Pea-sized piece of tissue located on

the inferior portion of the hypothalamus

Surrounding blood vessels carry hormones throughout the body

Posterior: Nervous tissue Neurosecretory cells in the tissue produce two hormones:

Oxytocin- contractions during child birth & release of breast milk

Antidiuretic hormone (ADH)- prevents water loss & reduces blood flow to sweat glands

Pituitary Gland Cont.Anterior:

Releases and inhibits hormones (six) of the hypothalamus: Thyroid stimulating hormone (TSH)- stimulation of

thyroid gland Adrenocorticotropic hormone (ACTH)- stimulation of

adrenal cortex Follicle stimulating hormone (FSH)- stimulation of

follicle cells (gonads) for production of gametes Luteinizing hormone (LH)- stimulation of the gonads

for production of sex hormones Human growth hormone (HGH)- stimulation of growth,

repair, and reproduction of cells all over the body Prolactin (PRL)- stimulates the mammary glands for

production of breast milk

Hypothalamus Part of the brain, located anterior and

superior to the brain stem, and inferior to thalamus

Controls the nervous systemProduces the hormones:

TRH GHRH GHIH GnRH CRH Oxytocin ADH

Pineal GlandPinecone shaped mass of tissue Located posterior to the thalamus in

the brainProduces melatonin to regulate the

sleep cycleIs activated when photoreceptors in

the retina receive light in low light & dark conditions

Increased production = drowsy

Thyroid GlandButterfly shaped mass Located at the base of the neckProduces three major hormones:

Calcitonin- released when calcium levels in the blood have risen

Triiodothyronine (T3)- helps regulate the body’s metabolism

Thyroxine (T4)- helps regulate the body’s metabolism

T3 and T4 both work together to adjust the body’s metabolic rate; increased levels leads to increased energy usage throughout the body

Parathyroid Glands Four small oval masses of tissueLocated on the posterior side of the

thyroid glandReleases a parathyroid hormone (PTH)PTH- calcium ion homeostasis; helps

stabilize the calcium levels in the blood by stimulating osteoclasts to break down calcium containing bone matrix; this calcium is then released into the blood stream

Adrenal GlandsA pair of triangular glands located superior

to the kidneysConstructed of two distinct layers:

◦ Adrenal Cortex: outer layer of adrenal glands; produces cortical hormones

Glucocorticoids- breakdown proteins and lipids to produce glucose as well as reduce inflammation and dictate an immune response

Mineralocorticoids- regulate the concentration of mineral ions in the body

Androgens- regulate the growth of cells that are receptive to hormones produced by males in the testes

Adrenal Glands Cont.◦ Adrenal Medulla: inner layer of the adrenal

glands; produces two hormones Epinephrine- adrenaline; hormone and neurotransmitter that

is released during a time of stress; “fight or flight” response Norepinephrine- similar to epinephrine; hormone released

when stressed; cognitive alertness These hormones affect the heart rate, breathing rate, blood

pressure, and help the body respond when in a high anxiety situation

PancreasLarge gland located in the abdominal

regionAlpha and Beta cells that are produced

here contribute to the process/production of glucose and glucagon

Alpha cells- production of glucagon which helps raise blood glucose levels; glucagon triggers a release of glucose into the bloodstream

Beta cells- production of insulin which helps lower blood glucose levels; insulin triggers the absorption of glucose

ThymusTriangular organ located in the

thoracic cavity anterior to the parathyroid glands

More apart of the immune system than the endocrine

Helps with the development of T-cells

GonadsResponsible for the production of

sex hormones in the bodyOvaries in females and testes in

males

OvariesPair of oval shaped glands located in

the pelvic cavity of a femaleResponsible for:

Estrogen- sex hormones; uterine development, breast development, growth of pubic hair, growth of bones (during puberty)

Progesterone- sex hormones; active during ovulation and pregnancy; implantation of the fertilized egg in the uterus

Production of egg cells

TestesPair of ellipsoid organs found outside

of the body in the scrotumResponsible for:

Testosterone- body hair, facial hair, production of sperm, growth of muscles, growth of sex organs, growth of bones, changes in voice

Endocrine System Videohttp://

www.youtube.com/watch?v=WVrlHH14q3o

Sites Used http://www.innerbody.com/image/endoov.html http://www.webmd.com/vitamins-supplements/ingredi

entmono-760-Pregnancy+Hormone+PROGESTERONE.aspx?activeIngredientId=760&activeIngredientName=Pregnancy+Hormone+(PROGESTERONE)&source=0

http://www.nlm.nih.gov/medlineplus/ http://

kidshealth.org/parent/general/body_basics/endocrine.html

http://www.livescience.com/26496-endocrine-system.html