Do Now (looseleaf)

1. What is the difference between a motor neuron, sensory neuron and an interneuron?

2. How do nerves communicate with one another?

3. How does a neurotransmitter know what receptor to go to? Explain

Do Now (looseleaf)

1. How do neurotransmitters and hormones travel around the body?

2. Where are neurotransmitters and hormones secreted from?

3. How are neurotransmitters and hormones similar?

4. Using your knowledge, predict which system causes a change in your body faster (endocrine or nervous)

Finish early:Work on Do Now #12

DO NOW #11

Complete section “G” on the back cover of your note packet (the one you received yesterday)

DO NOW

Complete (Section “E”)…one question Complete (Section “F”)…chart

ON BACK OF NOTE PACKET

DO NOW

Endocrine System

Glands, Hormones, Receptors,

Target Cell, Non-target Cell,

Negative Feedback

Endocrine System How does the endocrine system help maintain homeostasis?

Controls and coordinates the body’s response to changes in the environment using hormones!

Is this the same function as the nervous system? Explain

So are the nervous and endocrine systems the same thing? Explain

Yes! Both perform REGULATION

Are you crazy? NO- Nervous system uses nerves and

neurotransmitters- Endocrine system uses glands and

hormones

What organs are in the endocrine system?

Glands

Synthesize and secrete hormones

What are hormones?Hormones

Chemical signals secreted in one area of the body that affect other areas

Hormones are proteins with a specific shape

Travel in blood vessels Allow body to RESPOND to

CHANGE

How do hormones have a specific shape?*Hormones are proteins!

Sequence of amino acids determines shape of proteins

So, how do hormones work? Different glands secrete different

hormones Specific hormones are secreted into the

blood and travel everywhere in the body! Hormones only affect / attach to certain

cells, called target cells

How do hormones know what cells to affect or deliver a message to?

Target cells recognize specific hormones because hormones have specific shapes that only fit in certain cell receptors!

Specific Hormones & Specific Receptors

Hormones and receptors fit together like a: Lock and Key

Hormone

Secreting Cell(Gland Cell)

Can’t readsignal

Can’t readsignalNon-target

Cells

Why?

Target Cells

Receptors

Blood Vessel

Binding of a hormone to a receptor on the surface of its target cell causes…

A specific reaction

Lets take a look at the types of glands, hormones and the reactions they cause!

Glands of the Human Body

Pituitary Gland Also known as… The MASTER Gland Location - BRAIN

Hormone(s) Target(s) Function(s)

TSH (Thyroid Stimulating Hormone) Thyroid Gland

Causes Thyroid to secrete its hormone

Affects metabolism

FSH (Follicle Stimulating Hormone) Ovaries / Testes Stimulates sperm and egg

development

Growth Hormone Bones Stimulates elongation of the bones

Thyroid Gland Location - Neck

Hormone(s) Target(s) Function(s)

Thyroxine Various CellsIncreases metabolism, digestion and energy levels

Adrenal Gland Location – Top of Kidneys

Hormone(s) Target(s) Function(s)

Epinephrine / AdrenalineHeart

Blood VesselsSkin

Muscles

Emergency Response

“Fight or Flight” Response

Pancreas Location – Behind Stomach

Hormone(s) Target(s) Function(s)

Insulin Body CellsEspecially Liver & Muscle Cells

Lowers blood sugar levels

Stores sugar in in liver and muscle cells as glycogen

Glucagon Body CellsEspecially Liver & Muscle Cells

Raises blood sugar levels

Stimulates the release of sugar stored in liver cells

Gonads – Testes & Ovaries

Hormone(s) Target(s) Function(s)

Estrogen & Progesterone Ovaries & body cells

Influences development of female secondary sex characteristics

Testosterone Testes & body cellsInfluences development of male secondary sex characteristics

Type 1 Diabetes (insulin-dependent diabetes)• The body does not produce insulin. • Developed before 40th birthday, often in early adulthood or

teenage years. • Only about 10% of all diabetes cases are type 1. • Patients with type 1 diabetes will need to take insulin injections

for the rest of their life. They must also carrying out regular blood tests and following a special diet.

Type 2 Diabetes• Body does not produce enough insulin for proper function, or

the cells in the body do not react to insulin (insulin resistance).

How is hormone production regulated?

Hormones are NEVER released at a constant rate!Example:

Growth Hormone – If released at a constant rate… You would be a GIANT!! (Gigantism)

Hormones are released based upon…

The needs of the body

The mechanism that alters (stimulates or stops) the activity of a gland is usually an example of a

Example: Heating your home using a thermostat

If the home is cool, you raise the heat, thermostat, to 70⁰F and the home begins to warm up

FEEDBACK MECHANISM

What happens when 70⁰F has been reached?The heat will shut off because 70⁰F

was reached!The heat will turn back on when

the temperature is below 70⁰F

How does the process of Feedback work in your body?When is your blood glucose level high?

When is your blood glucose level low?

Types of Feedback:Positive Feedback – Negative Feedback –

Both Positive & Negative Feedback helps to…

hormone secretion continues hormone secretion STOPS

Maintain Homeostasis

Ingestion of Elevated Blood Secretion of Drop in blood Secretion of Starch causes Sugar Levels insulin is increased sugar levels insulin decreased

Are you ready?1. If liver cells usually have 100 insulin receptors each, and they

dropped down to only 50 each, what would happen?

2. Draw a neurotransmitter that would attach to this receptor:

Type 1 Diabetes (insulin-dependent diabetes)• The body does not produce insulin. • Developed before 40th birthday, often in early adulthood or

teenage years. • Only about 10% of all diabetes cases are type 1. • Patients with type 1 diabetes will need to take insulin injections

for the rest of their life. They must also carrying out regular blood tests and following a special diet.

Type 2 Diabetes• Body does not produce enough insulin for proper function, or

the cells in the body do not react to insulin (insulin resistance).

What is happening in this picture?

Blood pH lowersWhat happens next in this feedback process?

Lets compare the Nervous and Endocrine Systems

Review