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Endocrine SystemEndocrine System

□ Function:

- For glands to release products into

bloodstream to deliver messages

throughout the body.

Regulation

□ Is the control & coordination of other life functions to maintainHOMEOSTASIS (Stability)

Gland

Hormone

Target Cells

an organ made

of epithelial cells that makes & releases substances

Chemicals released in one area of the body, travels in bloodstream, & affects activities of cells in another area of the body

Cells with receptors specific for a hormone. If the shape does not match, the hormone has no effect

When You Think About The Endocrine

System, What Important Words Come

To Your Mind?

What Do Endocrine Glands Release (Secrete)?

Hormones

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After Organ Releases Hormones, Where Do Hormones

Travel Next?

Bloodstream

Where Do Hormones Travel After The Bloodstream?

To Target Cells

Would A Hormone Connect With

A Non-Target Cell? Why Or

Why Not?

No Specific Receptor For

The Hormone To Attach

Secreting Cells

Target Cells

Name 2 Examples Of Target Cells

Tissues or Glands

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Which 2 Organ Systems Work

Together To Regulate Other Organ

Systems?

Endocrine System

&

Nervous System

Comparing The

Nervous System Endocrine System

Impulses (electrochemical)

that carry messages that travel from one

cell to another cell.

TelephoneRadio Broadcast

Chemicals (hormones)

released that reaches almost every cell in

the body.

Made Up Of

Nervous System Endocrine System

Nerve cells (neurons) Glands

Electrochemical impulses released in synapse

Hormones(chemicals) released in bloodstream

Slow response

Short duration (short time)

Quick, rapid response

Long duration (longer time)

Controlled by

Response time

Effects

2 Types of Glands

- release hormones - release hormones

into ducts (tubes) directly into blood-

then to the organ. stream (ductless).

Ex: sweat Ex: thyroid

tears pancreas

digestive juices others

Exocrine

Glands

Endocrine

Glands

Exocrine Gland Endocrine Gland

Duct DuctlessExocrine or Endocrine Glands?

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Exocrine or Endocrine Glands?

?

List the Endocrine Glands

1. Hypothalamus Gland

2. Pituitary Gland

3. Thyroid Gland

4. Parathyroid Gland

5. Adrenal Gland

6. Pancreas

7. Ovaries

8. Testes

Thyroid

Gland

Parathyroid

GlandPituitary

Gland

Hypothalamus

Gland

Adrenal

Gland

Pancreas

Ovaries

(female)

Testes

(male)

Pituitary Gland

Thyroid Gland

Pancreas

Adrenal Glands

Testicles

(males)

Ovaries

(females)

Parathyroid Glands

Hypothalamus

Gland

Can You Explain How a Thermostat Works in Your

Home?

An Example of Homeostasis

□ Is controlled by Negative Feedback

(Feedback inhibition).

Negative Feedback

- the process where a stimulus

produces a response that opposes the original stimulus.

Ex: Thermostat ON, Increases Temp, Shuts OFF,

Decreases Temp, Thermostat ON

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Feedback Mechanism

□ A way to “self adjust”.

Endocrine Glands

□ Detects the proper amount of hormones in the body.

□ If not, will increase or decrease the hormone amount for proper regulation.

Feedback Mechanism

Example #1: Case Study

Mario ate two boxes of chocolate chip

cookies with a glass of milk. How do you think his body will help regulate the

excess sugar level in his bloodstream?

Let’s Use Our Chain of Events Diagram.

Pancreas secretes insulin

Lowers glucose, if glucose falls below set point

Pancreas secretes glucagon

Raises glucose, if glucose rises above set point

Glucose

Regulation

Pancreas secretes insulin into blood

to help sugar enter the cells.

Food Stomach

Pancreas

BloodstreamHappy cells

Dynamic Equilibrium

Homeostasis

Stability

Between Which Times Represent Stability

(Homeostasis) of Blood Sugar?

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Feedback Mechanism

Example #2: Case Study

Amanda went for a physical and the

doctor reported that her thyroid levels were normal.

Let’s Use Our Chain of Events Diagram.

Feedback Mechanism

Hypothalamus

Pituitary Gland

Thyroid Gland

Target Cells

Increase Metabolism

TRH

TSH

Thyroxine

H

I

G

H

Inhibit

Inhibit

L

O

W

Stimulate

Stimulate

Questions□ What will happen if Amanda’s blood

work showed a high thyroxine level?Her hypothalamus & pituitary glands will be inhibited (stopped) from releasing their substances. So no more thyroxine will be made.

□ What will happen if Amanda’s blood

work showed a low thyroxine level?Her hypothalamus & pituitary glands will be stimulated to release their substances. So more thyroxine will be made.

Glands

Pituitary Gland

□ Location: Bean shaped in base of skull.

□ Hormones: See chart

□ Function: Controls many body functions & actions of other glands

□ Disorders: Gigantism, Dwarfism

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Hypothalamus

□ Location: above & attached to posterior pituitary gland.

□ Hormone: TRH

□ Function:

1. Controls the secretions of the

pituitary gland.

2. Because the endocrine & hypothalamus are closely connected, the nervous & endocrine syst. coordinate body activities together.

Thyroid Gland

□ Location: Base of the neck

□ Hormone: Thyroxine (made of iodine)

□ Function: Regulate the body cells metabolism by increasing the rate of cellular respiration, protein, carb, & fat metabolism.

□ Disorders: Hyperthyroidism, Hypothyroidism, Cretinism

Parathyroidism Glands

□ Location: Back surface of the thyroid gland.

□ Hormone: PTH

□ Function: Increase calcium level in blood

promotes nerve &muscle function

help bone structure

Adrenal Glands

□ Location: two pyramids on top of kidneys

□ Hormones:

2 Parts:

1. Cortex: secretes corticosteriods, cortisol, aldosterone

2. Medulla: epinephrine, norepinephrine

□ Function: Help deal with stressful situations (fight or flight)

Adrenal Hormones

□ Aldosteroone- reabsorbs Na+, excretes

K+

□ Cortisol- control rate of metabolism: carbs, fats, proteins

□ Epi, norepinephrine- increase heart rate, sweating, wider airway passages,

increase glucose released, increase

BP, & blood flow.

Pancreas

□ Location: Abdomen

□ Hormone: Insulin & Glucagon from cells called

(islets of Langerhans)

- Beta cells produce insulin

- Alpha cells produce glucagon

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□ Function:

1. Insulin (decreases sugar) by stimulating liver & muscle cells to remove sugar in the blood.

2. Glucagon (increases sugar) by stimulating

liver to break down gylcogen into glucose & send into blood.

Gonads

□ Location:Ovaries

(females)

□ Hormone:

estrogen

progesterone

□ Functions:

1. Produce eggs

2. secrete sex hormones

□ Location: Testes

(males)

□ Hormone:

testosterone

□ Functions:

1. Produce sperm

2. Secrete sex hormones

Sex Hormones

□ Estrogen

- dev. Eggs

- breast dev.

- widening hips

- pubic hair

□ Progesterone

- prepares uterus for implantation

□ Testosterone

- dev. sperm

- facial hair

- increase body size

- deepening of

voice

Medical Disorders

Malfunctions

Medical Conditions

□ Diabetes-Pancreas produces a little or no insulin.□ Goiter- An enlarged thyroid gland due to iodine deficiency (not enough).

□ Gigantism-Excess (more) of growth hormone (GH) from a benign pituitary tumor.

□ Dwarfism-A deficiency (less) of growth hormone (GH), by the pituitary gland or a gene mutation.

Diabetes

□ Type1: Pancreas produces a little or no insulin.

□ Type2: Pancreas becomes resistant to effects of insulin or produces a little insulin.

� Effect: Raises blood sugar

� Treatment: Insulin, oral med., diet,

exercise

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Inactivity

Poor Diet

Overweight

Advancing

Age

Heredity

Diabetes Risk Thyroid Gland Disorders

Disorders:

1. Hyperthyroidism (to much thyroxine secreted)

-results in increased heart and metabolic rates,

increased blood pressure and weight loss.

2. Hypothyroidism (to little thyroxine secreted)

-results in lack of energy, weight gain, and

sometimes a “goiter” – enlargement of thyroid

Goiter

□ An enlarged thyroid gland due to iodine deficiency (not enough).

□ Can be from autoimmune condition.

� Effect: Not enough thyroid hormone made.

� Treatment: Iodine pills, hormone therapy pills.

Normal Thyroid Goiter

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Pituitary Gland Disorders

Disorders:

1. Gigantism: too much growth

hormone (GH) secreted in early

childhood

2. Dwarfism: too little GH

secreted in early childhood

Gigantism (Giantism)

□ Excess (overproduction) of growth

hormone (GH) from a benign pituitary

tumor.

� Effect: Causes overgrowth of long bones.

� Treatment: Surgery, radiation therapy, medication.

Dwarfism

□ A deficiency of growth hormone (GH),

by the pituitary gland or a gene

mutation.

� Effect: short stature (2ft 8in-4ft 8in)

� Treatment: surgery for bone problems,

hormone therapy (injections)