The Endocrine System

The Endocrine System

Controls many body

functions exerts control by

releasing special chemical substances into the blood called hormones

Hormones affect other endocrine glands or body systems Regulate growth,

development, metabolism, reproductive processes

Hormones need a specific receptor on a specific cell to do their job

Major Glands of the Endocrine systemPinealHypothalamusPituitaryThyroidParathyroidPancreasAdrenalOvariesTestes

The Glands

Hypothalamus Links the nervous

system to the endocrine system

Pineal Gland Located in the brain

and produces melatonin

The Pituitary Gland

• Pituitary gland: a small gland located on a stalk hanging from the base of the brain – AKA The Master Gland – Primary function is to

control other glands.– Produces many

hormones.– Secretion is controlled by

the hypothalamus in the base of the brain.

The Pituitary Gland

The Pituitary Gland is divided into 2 areas, which differ structurally and functionally each area has separate

types of hormone production.

The two segments are the Posterior and Anterior pituitary

The Hormones of the Pituitary

The two segments are: Posterior Pituitary produces:

– oxytocin – antidiuretic hormone (ADH)

Anterior Pituitary produces: thyroid-stimulating hormone (TSH) growth hormone (GH) adrenocorticotropin (ACTH) follicle-stimulating hormone (FSH) luteinizing hormone (LH) Prolactin (PRL) Melanocyte stimulating hormone (MSH)

The Thyroid Gland

Lies in the anterior neck just below the larynx

Has two lobes located on either side of the trachea (connected by a band of tissue called isthmus)

Sacs within the gland are called colloids and within them are the hormones: Thyroxine (T4) Triiodothyronine (T3) Calcitonin

The Parathyroid Gland

Small, pea-shaped glands, located in the neck near (para) the thyroid

Most people usually have 4Produces Parathyroid hormone (PTH)

The Pancreas

Islets of LangerhansA key gland (also considered an organ in

the digestive system!!) located near the folds of the duodenum

Has both endocrine and exocrine functionsHas a specialized tissue called Islets of

Langerhans, in which endocrine functions occurs include 3 types of cells which secrete an important

hormone: alpha ( ) beta () delta ()

The PancreasAlpha cells () release glucagonBeta Cells () release insulin (antagonistic

to glucagon)Delta Cells () produce somatostatin

The Adrenal Gland

It is two small glands located atop of both kidneys

Each has two divisions with different functions Adrenal Medulla secretes (ties in closely with the

sympathetic component of ANS): Norepinephrine Epinephrine

Adrenal Cortex secretes: Gluticocorticoids Mineralocorticoids Androgenic hormones

Gonads

Associated with human reproduction: Female-ovaries, Male-testis

Both genders are controlled by: Luteinizing Hormone (LH) Follicle stimulating hormone (FSH)

Ovaries Located in the abdominal cavity adjacent to the uterus (produces eggs) Hormones it produces:

Estrogen (E) Progesterone (some) Testosterone (T)

Testis Located in the scrotum (produces sperm) Hormones it produces:

Testosterone (T)