THE ENDOCRINE SYSTEM

SOAR Biology –

Mr. Najera

WHAT IS THE ENDOCRINE SYSTEM?Remember: A group of Organs & Glands make up a system.

It Has two main functions: Produces Chemicals that control

many of the body’s daily activities.

Regulates long term changes such as growth and development.

THE ENDOCRINE GLANDS

The Endocrine Glands produce chemicals that are released directly into the bloodstream to be spread throughout the body rapidly.

Controls body reactions like a FEAR responses: sweating, rapid heartbeat

Describe in your notes how you physically feel when you are scared.

HORMONES

The chemicals produced by endocrine glands are called HORMONES. Turn off, turn on, speed up, or slow down the activities

of certain organs and tissues. A “CHEMICAL MESSENGER.”

Lasts longer than a nerve impulse.

Won’t end until hormone wears off.

Make up your own sentence

Using the word HORMONE.

HORMONE PRODUCTION

What cause production of hormones? Impulses from the brain trigger

production. When we see danger, eyes send

impulse to brain. Brain sends message to glands. They look for target cells, just like

viruses. Glands release hormones. Ex.

Adrenaline When might you use adrenaline?

Glands / Organs• Pituitary: regulates

growth, blood pressure, water balance.

• Thyroid: release of energy from food.

• Parathyroids: regulate calcium in the blood.

• Pineal gland: melanin: controls sleep cycle.

• Hypothalamus: controls pituitary gland. Talks to nervous system.

• Adrenals: emergency respnse, salt, h20 balance, sugar in blood.

• Pancreas: insulin and digestive enzymes.

• Ovaries: estrogen: eggs dev. , changes in female body.

• Testes: testosterone: male body changes, sperm production.

OTHER TYPES OF HORMONES FROM THE PITUITARY GLAND.

Growth hormone: which stimulates the growth of bone and other body tissues and plays a role in the body's handling of nutrients and minerals

Prolactin, which activates milk production in women who are breastfeeding

Thyrotropin, which stimulates the thyroid gland to produce thyroid hormones

Corticotropin, which stimulates the adrenal gland to produce certain hormones

Hormones that also regulates the menstrual cycle in women.

NEGATIVE FEEDBACK –STOP SIGN When the amount of a certain hormone in the blood

reaches a max level, the endocrine system sends a signal to stop production of that hormone.

“all the receptors are full” so the back flush signals the original producer to stop.

CHECK FOR UNDERSTANDING: ANSWER IN YOUR NOTES…

1. What is the Role of the Endocrine system?

2. How does the chemical message stop?

3. How is the target cell activity function like a

virus?

THINGS THAT CAN GO WRONG…Too much or too little of any hormone can be harmful to the body. For example, if the pituitary gland produces too much growth hormone, a child may grow excessively tall. If it produces too little, a child may be abnormally short.

DYSFUNCTIONS OF THE ENDOCRINE• Adrenal insufficiency:

characterized by underproduction of adrenal corticosteroid hormones. The symptoms of adrenal insufficiency may include weakness, fatigue, abdominal pain, nausea, dehydration, and skin changes. Doctors treat adrenal insufficiency by giving replacement corticosteroid hormones.

DYSFUNCTIONS OF THE ENDOCRINE

• Cushing syndrome. (Over production of Hormones.) Symptoms include obesity, growth failure, muscle weakness, easy bruising of the skin, acne, high blood pressure, and psychological changes. Doctors treat this with surgery, radiation therapy, chemotherapy, or drugs that block the production of hormones.

DYSFUNCTIONS OF THE ENDOCRINEType 1 diabetes. When the pancreas fails to produce enough insulin, type 1 diabetes occurs. Symptoms include excessive thirst, hunger, urination, and weight loss.Type 1 diabetes can cause complications, including kidney problems, nerve damage, blindness, and early coronary heart disease and stroke. To control their blood sugar levels and reduce the risk of developing complications, people need regular injections of insulin.

Type 2 diabetes.

in type 2 diabetes the body is unable to respond to insulin normally. People with this condition tend to be overweight, and it is believed that excess body fat plays a role in the insulin resistance that characterizes the disease.

People can control their blood sugar level with dietary changes, exercise, and oral medications, but many will need to take insulin injections like those with type 1 diabetes.

CHECKING FOR UNDERSTANDING What should you do to prevent diabetes?

Why do we need a steady controlled production of Hormones?

What happens if there are too little hormones being produced?

Why is it necessary for the Endocrine system to regulate / shut off Hormone production at some point? (i.e. Negative Feedback)

List something you learned from Tuesday or today that you did not know or had not heard of.