SOMEWHERE . . . OVER THE BRAINBOW . . . The Central Nervous System, Peripheral Nervous System, the Neuron, and other stuff!

FUN FACTS ABOUT LE BRAIN. Neurons: Milky Way

100 Billion-

300 Billion-

15ft-

10 minutes-

No pain

4 times around the earth!

Convolutions are Key!!!

Gyri and Sulci

OUTLINE: HERE’S WHAT WE’RE GOING TO LEARN!

THE NERVOUS SYSTEM: The Purpose of the Nervous

System The different parts of the

CNS/PNS Anatomy of a neuron Synapse Transmission of a signal Major Parts/Function of the brain

WHAT IS THE PURPOSE OF THE NERVOUS SYSTEM? 1. It acts as a network with

all the nerve cells throughout your whole body.

2. It controls all the systems in your body by sending messages in between your brain and your body.

3. It stores memories, and allows you to think.

ORGANIZATION OF THE NERVOUS SYSTEM CNS: The Brain and spinal cord PNS: Sensory and motor neurons

Subdivided into Autonomic + Somatic Nervous system Autonomic is subdivided into Sympathetic +

Parasympathetic

SOMATIC NERVOUS SYSTEM:VOLUNTARY NERVOUS SYSTEM Smiling Walking Arm Wrestling

Sensing stimuli Responding to

stimuli

THE AUTONOMIC NERVOUS SYSTEM : INVOLUNTARY NERVOUS SYSTEM

consists of sensory neurons and motor neurons that run between the central nervous system and various internal organs such as the:

heart lungs glands (both exocrine and endocrine)

Monitors different aspects of homeostasis, adjusts as necessary.

MetabolismTemperature RegulationHeart beat, etc.

Controls contraction of smooth and cardiac muscle

SYMPATHETIC VS. PARASYMPATHETIC

SYMPATHETIC VS. PARASYMPATHETIC Sympathetic

stimulates heartbeat raises blood pressure dilates the pupils dilates the

trachea and bronchi shunts blood away from

the skin and viscera to the skeletal muscles, brain, and heart

inhibits peristalsis in the gastrointestinal (GI) tract

inhibits contraction of the bladder and rectum

Parasympathetic

•slowing down of the heartbeat (as Loewi demonstrated)

•lowering of blood pressure

•constriction of the pupils

•increased blood flow to the skin and viscera

•peristalsis of the GI tract

NEURON ANATOMY Sensory neurons carry

signals from the outer parts of your body (periphery) into the central nervous system.

Motor neurons (motoneurons) carry signals from the central nervous system to the outer parts (muscles, skin, glands) of your body.

Interneurons connect various neurons within the brain and spinal cord.

BREAK IT DOWN. Cell Body (Soma)- Control

center / Recycling center

Dendrites- Receive signals from other neurons

Axon- Conducts signals away from the cell body to terminals

Myelin Sheath- Speeds neural signaling

Dendrites Axon

Cell Body

Myelin Sheath

Terminal

I have many entry points to receive signals, and one point

to send a signal!

Neuron Photoshoot!

Neurons and astrocytes isolated from rat hippocampus stained for DNA (blue), neuronal-specific βIII-tubulin (green) and astrocyte-specific GFAP (red)

LARGEST NEURONS: I “CEPHA-LOVE” GIANT AXONS! UP TO 1 MM THICK!!!!!!

Unbelievable.

SYNAPSE: SIGNALING JUNCTION Neurotransmitters:

Acetylcholine

Inhibitory Endorphin Dopamine Seratonin

Excitatory Norepinephrine Epinephrine

LIGHTS, CAMERA, ACTION POTENTIAL! STEPS FOR AP! 1. Action Potential arrives

at axon terminal 2. Ca channels open, Ca

enters axon terminal 3. Ach is released into

cleft, Ca is pumped out of axon terminal

4. Ach binds to receptors 5. Action Pot. is generated

and propogated 6. Causes release of Ca

ions 7. Ca ions trigger muscle

contraction

http://www.youtube.com/watch?v=yQ-wQsEK21E

THE BRAIN!!!!! A NICE, SWEET MEAT! Separated into two

hemispheres Right= Creative Left= Analytical

Connected by Corpus Collosum

Consists of 4 lobes Frontal Lobe Parietal Lobe Temporal Lobe Occipital Lobe

FRONTAL LOBE: Functions of the frontal

lobe! Emotions Reasoning Planning Movement Parts of speech Creativity Judgement Problem-solving Planning

TEMPORAL LOBE: Functions of the

Temporal Lobe: Hearing Memory Meaning Language Emotion Learning Interpreting and

processing auditory stimuli

PARIETAL LOBE: Functions of the

Parietal Lobes:

Processing of nerve impulses related to senses Touch Pain Taste Pressure Temperature

Language

OCCIPITAL LOBE: Functions of the

Occipital Lobe: Object Recognition Vision

ORDER OF THE BRAIN: TAKE TWO! Medulla Oblongata

Unconscious, essential functions

Circulation, muscle control, breathing, digestion etc.

Cerebellum Motor coordination, balance Enlarged in birds

Pons Connects forebrain and

hindbrain Sleep and arousal

FOREBRAIN, MIDBRAIN, HINDBRAIN The Brain uses more

oxygen and energy than any other organ

Midbrain and Hindbrain - Brainstem

Connects CNS and PNS Homeostasis and

coordination Forebrain

Cerebrum Greatly enlarged in

mammals Information processing

CORTICAL HOMUNCULI