Neuron (Nerve Cell)• Myelin Sheath• Cell Body

– Nucleus• Axon

– Carry messages away from the cell body to other neurons

• Axon Terminal• Dendrites

– Carry messages to the cell body

2003-2004

signaldirection

myelin coating

Myelin Sheath Axon coated with insulation

made of myelin cells (Fatty, protein substance) speeds electrical signal 330 mph vs. 11 mph

Multiple Sclerosis immune system (T cells) attacks myelin coating loss of signal

Types of neuronssensory neuron(from senses)

interneuron(brain & spinal cord)

motor neuron(to muscle)

1. Receptor Cells Receives information from a stimulus

• For example - your finger gets hit by a hammer

2. Sensory Neurons (Monitor Change)– Carry the impulse to the spinal cord

• Travels the length of the arm to the spinal cord

3. Interneuron (Process & Interpret)Impulse is transmitted to the brain and the

motor neurons via synapsesTravels to the brain to register pain and out to

the finger

4. Motor neurons (Generate Response)– Sends the processed information back to

finger• Carries impulse to the effector cells in the

fingers, hand and arm

Types of Neurons

2003-2004

Simplest Nerve Circuit Reflex, or automatic response

rapid response automated

signal only goes to spinal cord no higher level

processingadvantage

essential actions don’t need to think or

make decisions about blinking balance pupil dilation startlehttp://www.youtube.com/wat

ch?v=2Ko0Zuv4Z64

Synapse

synapse

Junction between nerve cells– 1st cell releases chemical to trigger

next cell (Neurotransmitter) – where drugs affect nervous system

Nervous System• Two MAJOR divisions

1. Central Nervous System (CNS)

• brain and spinal cord

2. Peripheral Nervous System

• nerves• Ganglia

– Collections of nerves– Two MINOR divisions

» Somatic and autonomic

2003-2004

                                                                                                                                                                                                                                                                           Research Visit the Glencoe Science Web site at tx.science.glencoe.com for more information about the nervous system. Make a brochure outlining recent medical advances.

The Peripheral Nervous System Your brain and spinal cord are connected to the rest of your body by the peripheral nervous system. The PNS is made up of 12 pairs of nerves from your brain called cranial nerves, and 31 pairs from your spinal cord called spinal nerves. Spinal nerves are made up of bundles of sensory and motor neurons bound together by connective tissue. For this reason, a single spinal nerve can have impulses going to and from the brain at the same time. Some nerves contain only sensory neurons, and some contain only motor neurons, but most nerves contain both types of neurons.

Somatic and Autonomic Systems The peripheral nervous system has two major divisions. The somatic system controls voluntary actions. It is made up of the cranial and spinal nerves that go from the central nervous system to your skeletal muscles. The autonomic system controls involuntary actions-those not under conscious control-such as your heart rate, breathing, digestion, and glandular functions. These two divisions, along with the central nervous system, make up your body's nervous system.

Acupuncture

• Traditional Chinese medicine: – Balance Chi ( life force energy)– Points in body allow better flow of

Chi– energy flow will re-balance.

• Western practitioners – acupuncture points as places to

stimulate nerves, & muscles. – boost the activity of your body's

natural painkillers – increase blood flow.

Acupuncture loci vs.

Peripheral Nerve loci

Parasympathetic vs. Sympathetic

The diagram below represents part of a capillary in a specific region of the human body. The region labeled X represents part of 1.a glomerulus2.an alveolus3.a villus4.the liver

Quick Practice

The diagram below represents part of a capillary in a specific region of the human body. The region labeled X represents part of A. a bronchiB. an alveolusC. a villusD. A heart

Quick Practice• A biochemical compound

(i.e. proteins) that readily combines with oxygen and distributes it throughout the human body is

A. ureaB. waterC. acetylcholineD. hemoglobin

The body cells of most multicellular animals are not in direct contact with the external environment. These cells are supplied with materials from the environment by

A. a central nervous systemB. hydrolytic enzymesC. sense receptorsD. a circulatory system

Quick Practice

• Which of the following is/are type(s) of neurons?

A)sensoryB)motorC)interneuronsD)all of the above

• Sensory nerve cells act as the decision-making cells to sum up all signals for certain stimuli.

A)TrueB)False

Quick Practice

• The peripheral nervous system includes mixed nerves that _________.

• A)serve the muscular and skeletal system• B)serve the sympathetic system• C)serve the parasympathetic system• D)contain both sensory and motor fibers

Chemical Regulation!

• Endocrine System: Through chemicals released into the bloodstream, this system regulates overall metabolism, homeostasis, growth, mood, & reproduction.

• Chemical signals called hormones are created in

glands. (see naked person to the right)

• Works with the nervous system to accomplish regulation.

• Example: Fear + Adrenaline

• http://www.youtube.com/watch?v=NX7QNWEGcNIhttp://www.youtube.com/watch?v=NX7QNWEGcNI

• Parkour

• http://dsc.discovery.com/tv-shows/other-shows/videos/adrenaline-lab-jeff-wise-explains-adrenalines-power.htm

• How Adrenaline works

• Endocrine glands:– “Ductless” glands. Produce &

secrete chemicals into blood– However, hormones will only

affect specific cells with receptors

• Target tissue:– Specific tissue (group of cells)

that recognizes each type of hormone. Is either stimulated (start or speed up) or inhibited (stop or slow down).

The Regulation of Hormone Secretion

• Rate of secretion varies with the needs of the body• Like when your hyperglycemic

• Endocrine & Nervous system teamwork• Hypothalamus

• Feedback regulates glandular secretions:• Negative Feedback• Positive Feedback

What’s happening in the loops?

What are the hormones(chemical messengers) involved?

Target cells?

Are they released all the time? Every day at 1pm? Once a year? Does it vary?

• Negative Feedback & Stability:– Tends to keep a variable close to

some value (set point).– Ex: Blood glucose conc., or body

temp.– MUST MAINTAIN

HOMEOSTASIS!

• Positive Feedback & Rapid Change– The response intensifies the

original change.– i.e : Baby Cry Oxytocin Milk

Production

“How Bad Is It Doc?”• Research an endocrine disorder for

homework. (citations required) • Pick a gland• What is the normal function of this gland?

– Hormone secreted– Target cell

• Explain what happens when homeostasis fails? (for example, what over-secretion or under-secretion causes. List and briefly describe any disease names you may find)

• What are the clinical symptoms of the disorder?• What treatment is currently available for

sufferers?• Find at least 2 images of ppl infected, if possible• Be prepared to get into small groups and create a

collaborative table

• Gland Options– Pituitary– Hypothalamus– Thyroid– Parathyroid– Adrenal– Pancreas– Testis– Ovaries

Portfolio• To be completed over

next 3 weeks

• Today, Wednesday, Thursday, Friday your topic is the nervous and Endocrine systems

• Homework will also include portfolio work

• By Thursday (Class’ end)– Gather information

covering all requirements per system

– Continue multimedia formatting of evidence

• By Friday (Class’ end) – I should be reviewing your

multimedia evidence for accuracy and misconception

– Finalize evidence of nervous and endocrine systems