Endocrine System

The Endocrine System is made up
of ______, which are located all
over the body

Glands

as well as _______, or chemicals that they release

hormones

These hormones are
transported by the _________ of
the blood.

circulation

What is the main function of the endocrine system?

1) Maintain homeostasis, help organisms respond to their enviroment

What life process does the endocrine system carry out in the human body?

Regulation

What cell organelle carries out this life process in a single-celled organism?

Nucleus

An organ that produces and releases a substance

Gland

Release substances into ducts, ex. salivary glands, sweat glands

Exocrine glands

DO NOT have ducts, substances released into the bloodstream

Endocrine glands

Chemicals that travel through the bloodstream and effect activities of other cells or organs

Hormones

specific cells/organs that the hormone affects

Target cells/organs

Receptor protiens

special proteins located on or in the target cell that combine with a specific hormone to produce a response

Where are glands of the endocrine system?

They’re scattered throughout the body

What are the major glands of the body?

pituitary, hypothalamus, pineal gland, thyroid, parathyroid, thymus, adrenal, pancreas, ovaries, and testes

Where is the pituitary gland located?

At the base of the brain

What is the pituitary gland called

The master gland because it controls the activities of many other glands

What hormones does it produce

Human Growth Hormone (HGH) ○ Thyroid Stimulating Hormone (TSH)- stimulates thyroid to release thyroxin ○ Follicle Stimulating Hormone (FSH)- stimulates growth of follicle in ovaries and sperm production in testes

Where is the hypothalamus located

Just above the pituitary

What does the hypothalamus control

Many hormones released by pituitary

What hormones does hypothalamus produce

Antidiuretic Hormone (ADH): promotes water reabsorption by kidneys ○ Growth-hormone- releases hormone that stimulates release of GH from pituitary

Where is the pineal gland located?

In the center of the brain

What does the pineal gland produce

Melatonin, which regulates sleep/wake cycle

Where is the thyroid located?

In the neck

What does the thyroid produce?

Thyroxin: regulates metabolism by increasing the rate of cell respiration o Calcitonin: Decreases blood calcium levels

Where are the parathyroid gland located?

Four small glands embedded within the thyroid gland

What does the parathyroid gland produce?

Produces parathyroid hormone (PTH): Increases blood calcium levels

Where is the thymus located?

Behind the breastbone

When the thymus mainly active?

Mainly active during childhood (it begins to degrade during puberty)

What hormones does the thymus produce?

Thymosin: Increases the immune response and causes release of Growth Hormone

Where are the adrenal glands located?

On top of kidneys?

What hormones do the adrenal glands produce?

Adrenaline- released during the “flight or fight” response o Cortisol- helps control metabolism of carbs, fats, and proteins, usually released more in times of stress

Where is the pancreas located?

Above the stomach

What does the pancreas produce?

Insulin- lowers blood sugar levels by stimulating cells in the liver and muscles to remove sugar from the blood and store it as glycogen or fat.

Glucagon- raises blood sugar levels by stimulating the liver to break down glycogen and release glucose back into the blood

What do ovaries produce?

Estrogen- female secondary sex characteristics o Progesterone- controls menstruation and pregnancy

What do testes produce?

Testosterone- male secondary sex characteristics

How is the release of hormones controlled?

The hormones produced by endocrine glands are regulated by a feedback mechanism, which is a self-regulating system.

What is negative feedback?

it occurs when the level of one hormone in the bloodstream, will typically inhibit the secretion of another hormone

Negative feedback example for pancreas

Pancreas detects high blood sugar level,

Pancreas secretes insulin ,

Blood sugar level drops

Lowered blood sugar leads to shutting off of insulin production

What is goiter and how is it caused?

Enlargement of
the thyroid
● Caused by a lack
of iodine in the
diet or by
increased release
of TSH (thyroid
stimulating
hormone) by the
pituitary

What is HYPERthyroidism?

Too much thyroxine produced o Symptoms: Increased heart rate, metabolism, body temperature, weight loss

What is HYPOthyroidism?

Too little thyroxine produced o Symptoms: Decreased metabolism and heart rate, weight gain, lack of energy

What is type 1 diabetes

Typically diagnosed before age 15, Pancreas secretes little to no insulin, Daily insulin injections required o Autoimmune Disorder

Type II Diabetes (Adult Onset)

Usually diagnosed during middle age, Insulin is produced but insulin receptors on body cells do not respond to insulin in the blood, Associated with obesity, Can be reversed