The Nervous System

Get into Partners Read a slide and talk about the slide--- 1 slide at a time! The slides with the yellow star in the corner are the most important! Take notes & Write down any questions you have as you are learning and discussing each slide. Teach and explain to each other what you take away from each slide. You will answer questions without the use of notes at the end, so make sure you are learning. ***Stop right before Diagnostic, Procedural & Lab Terms***

Divisions of the Nervous System Nerves

What is the nervous system? Each day, you use verbal and nonverbal communication as a signal to others. For example, to signal a student has a question, he/she would raise his/her hand. The teacher would recognize this signal and direct his/her attention to the student. Your body works in much the same way. The nervous system is one of your body’s personalized communication systems. Signals are sent from one location to another in order to control and coordinate many bodily functions. The nervous system responds to internal and external stimuli.

Neurons Are cells, which transmit electrical signals or impulses Provide a pathway for messages going to and from the brain and spinal cord

Neurons Characteristics: have a cell body, which is the largest part have processes are fiber-like extensions increase the distance at which signals can be transmitted two types of processes: dendrites -- carries signal to the cell body axons -- carries signal away from cell body

Cell body Myelin sheath Axon Neurons Axon terminals Nucleus Dendrites

Dendrites Neurons Transmit signals toward the body Are short and branch extensively Neurons may have dozens of dendrites Are bound with axons to form a nerve pathway Neurons

Axons Neurons Transmit signals away from the body Most neurons have only one very long axon Gaps between synaptic knobs are called synapses Neurons

Supporting Cells Myelin sheath cover the axon for protection aid in delivery of impulses traveling through the axon by insulating the nerve

Synapse Is the location where neurons transfer impulses between cells Are gaps separating the axon terminal from dendrites of adjacent cell Have terminals containing sacs filled with neurotransmitters are chemicals used by neurons to transmit impulses across a synapse to another cell

The Two Major Divisions Central nervous system central processing system of the nervous system -- much like the main processing chip of a computer 2. Peripheral nervous system relays information received from the central nervous system to organs and glands

Central Nervous System

Components Brain Spinal Cord

Brain Is the central control unit for the body Is protected by the skull cerebrospinal fluid (CSF) occupies space between two layers functions as a shock absorber allows for the exchange of nutrients and waste between blood and nervous tissue

Brain Divided into: cerebrum cerebellum brain stem Did you know the average adult human brain weighs about 3 lbs.?

INJURY to this can lead to COMA!! Brain Stem Connects brain and spinal cord Is located beneath the cerebellum Has two regions, which act as a control system, regulating information between the brain and body medulla oblongata Pons INJURY to this can lead to COMA!! Brain

Spinal Cord Is enclosed in the vertebral column Is a continuation of the brain stem Serves as the main communication link between the brain and body Functions to: transmit impulses to and from the brain control several reflex actions

Peripheral Nervous System

Components Divided into two parts: Motor Division Sensory Division relays impulses from the central nervous system to muscles and glands Sensory Division relays impulses from sensory organs to the central nervous system

Diagnostic, Procedural and Lab Terms

Electroencephalogram: EEG, measures electrical impulses in the brain CT/ CAT: shows cross section images of the brain Myelogram: picture of spinal cord after a contrast is injected Cerebral Angiogram: picture of the brain’s blood vessels after a contrast has been injected Reflexes: involuntary muscle contractions responding to a stimulus Babinski’s : reflex on bottom of foot

Diseases and Abnormalities

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Brain Neuron Axon Central Nervous System Myelogram Babinski Coma Cerebrum Concussion -otomy -plegia Psych/o EEG Crani synapse

Spinal Cord Nerve Dendrite Peripheral Nervous System Electroencephalogram -cyte Brain stem Cerebellum Ambul neurotransmitter -al Cerebral Angiogram synapse Crani Myel

Concussion: injury to brain from impact Coma: abnormal deep sleep with little or no response to stimuli Brain contusion: bruise to brain Shaken baby syndrome: closed head trauma; brain hitting skull Alzheimer’s: degeneration of neurons in the brain Amnesia: loss of memory CVA: stroke, cerebrovascular accident; lack of o2 to brain Epilepsy: seizure; abnormal electrical impulse Aura: the feeling before a seizure

Hydrocephalus: water on the brain (CSF) Tourette syndrome: neurological disorder with uncontrollable sounds and tics Paralysis: loss of feeling and movement Hemiplegia paraplegia Syncope: fainting

3-2-1 Summary Write… 3 things you learned 2 examples, applications to real life or conclusions about what you learned 1 question Stand up, find a partner, “walk and talk” sharing your summaries. Add at least 2 more ideas to your summaries