Download The Nervous system

THE NERVOUS SYSTEM
THE NERVOUS SYSTEM
• BRAIN
• SPINAL CORD
• NERVES
• SENSE ORGANS
FUNCTIONS OF
THE NERVOUS SYSTEM
• 1. RECEIVING INFORMATION
•
YOU ARE AWARE OF WHAT IS HAPPENING BOTH INSIDE AND OUTSIDE THE BODY
• 2. RESPONDING TO INFORMATION
•
STIMULUS – ANY CHANGE OR SIGNAL IN THE ENVIRONMENT THAT CAN MAKE AND ORGANISM REACT
•
RESPONSE – WHAT THE BODY DOES IN REACTION TO A STIMULS
• 3. MAINTAINING HOMEOSTASIS
•
DIRECTS THE BODY TO RESPOND APPROPRIATELY TO THE INFORMATION IT RECEIVES
DIVISIONS OF
THE NERVOUS SYSTEM
• CENTRAL NERVOUS SYSTEM
•
ALL INFORMATION ABOUT WHAT IS HAPPENING IN THE WORLD INSIDE AND/OR OUTSIDE THE BODY IS
BROUGHT TO CENTRAL NERVOUS SYSTEM
•
CONTROL CENTER OF THE BODY
•
CONSISTS OF THE BRAIN AND SPINAL CORD
DIVISIONS OF THE NERVOUS SYSTEM:
CENTRAL NERVOUS SYSTEM
• 3 MAIN REGIONS OF BRAIN
•
• BRAIN
• CONTROLS MOST FUNCTIONS
• CONTAINS
NEURONS
APPROX.
IN BODY
100 BILLION
•
•
1. CEREBRUM
•
INTERPRETS INPUT FROM THE SENSES
•
CONTROLS MOVEMENT
•
CARRIES OUT COMPLEX MENTAL PROCESSES
2. CEREBELLUM
•
COORDINATES THE ACTIONS OF YOUR MUSCLES
•
HELPS MAINTAIN BALANCE
3. BRAIN STEM
•
CONTROLS THE BODY’S INVOLUNTARY ACTIONS
DIVISIONS OF THE NERVOUS SYSTEM:
THE CENTRAL NERVOUS SYSTEM
• SPINAL CORD
•
THE LINK BETWEEN THE BRAIN AND THE PERIPHERAL NERVOUS SYSTEM
DIVISIONS OF
THE NERVOUS SYSTEM
• PERIPHERAL NERVOUS SYSTEM
•
CONSISTS OF A NETWORK OF NERVES THAT BRANCH OUT FROM THE CENTRAL NERVOUS SYSTEM AND
CONNECT IT TO THE REST OF THE BODY
•
INVOLVED IN BOTH INVOLUNTARY AND VOLUNTARY ACTIONS
•
TOTAL OF 43 PAIRS OF NERVES
DIVISIONS OF THE NERVOUS SYSTEM
PERIPHERAL NERVOUS SYSTEM
• DIVIDED INTO 2 GROUPS
• 1. SOMATIC NERVOUS SYSTEM
• CONTROLS VOLUNTARY ACTIONS
• 2. AUTONOMIC NERVOUS SYSTEM
• CONTROLS INVOLUNTARY ACTIONS
THE NERVOUS SYSTEM
• REFLEXES
•
AN AUTOMATIC RESPONSE THAT OCCURS VERY RAPIDLY AND WITHOUT CONSCIOUS CONTROL
• SIGNALING THE BRAIN
•
NERVE IMPULSES REACH BRAIN AND ARE INTERPRETED
•
TAKES LONGER FOR THE PAIN IMPULSE TO REACH BRAIN AND BE INTERPRETED THEN IT DOES FOR THE REFLEX
ACTION TO OCCUR
THE NERVOUS SYSTEM
• NERVOUS SYSTEM INJURIES
• CONCUSSION
•
A BRUISELIKE INJURY OF THE BRAIN
• SPINAL CORD INJURIES
•
OCCUR WHEN SPINAL CORD IS CUT OR CRUSHED
THE NERVOUS SYSTEM
• NEURONS
• CELLS THAT CARRY INFORMATION
THROUGHOUT THE NERVOUS
SYSTEM
THE NERVOUS SYSTEM
NEURONS
• 3 KINDS OF NEURONS
• 1. SENSORY NEURONS
• PICKS UP STIMULI FROM INTERNAL
OR EXTERNAL ENVIRONMENT AND CONVERTS INTO A NERVE IMPULSE
• 2. INTERNEURON
• CARRY NERVE
IMPULSES FROM ONE NEURON TO ANOTHER
• 3. MOTOR NEURONS
• SENDS NERVE IMPULSES TO A MUSCLE OF GLAND AND THE MUSCLE OR GLAND REACTS IN RESPONSE
THE NERVOUS SYSTEM
• NERVE IMPULSE
• MESSAGE THAT A NEURON CARRIES
• BEGIN IN DENDRITE, MOVE TOWARD THE CELL BODY, THEN MOVE DOWN THE AXON
• SYNAPSE
• JUNCTION WHERE ONE NEURON CAN TRANSFER AN IMPULSE TO ANOTHER