What is the function of the nervous system? Sensory Input: action of getting information from the surrounding environment. Things are being sent to the brain by way of the senses (touch, smell, see, etc.) Integration: the interpretation or translation of things that have been touched, smelled, seen, etc. Takes place in the brain.
What is the function of the nervous system? Motor Output: After your brain has interpreted all that has been by using your senses, then your brain sends a message through neurons to muscles or other cells which work to perform the response.
The Nervous System *The nervous system is divided into 2 parts: *Central Nervous System: the brain, spinal cord, and association neurons *Peripheral Nervous System: all the nerves outside the CNS
Central Nervous System The body’s most rapid means of maintaining homeostasis. Regulates bodily functions by sensing changes within the body and from the environment. Makes adjustments by delivering impulses which results in muscular contractions and/or glandular secretions.
Central Nervous System Association neurons: make up most of the spinal cord. Change input impulses to output impulses and cause the body to respond.
Peripheral Nervous System
There are two types of neurons in this system, sensory neurons and motor neurons Sensory Neurons: sends information to CNS from internal organs and from environment and motor neurons. The motor neurons send impulses to voluntary and involuntary muscles.
Peripheral Nervous System Motor Neurons : divided into somatic and autonomic nervous system Somatic nervous system: controls skeletal muscles and external sensory organs such as the skin. System is voluntary, except for reflex reactions of skeletal muscles.
Somatic Nervous System
Peripheral Nervous System Autonomic Nervous System: Controls involuntary muscles such as the smooth and cardiac muscle. Also called the involuntary nervous system.
Autonomic Nervous System
Nerve Cells Neurons Basic functioning units of the nervous system
Neurons Made up of a cell body and branches called dendrites and axons Dendrites receive messages from other neurons and send them to the cell body Axons carry messages away from the cell body
Any message carried by a neuron is called an impulse
Neurons A message carried by a neuron is called an impulse
Types of Neurons Sensory Motor Association
Sensory Neurons Receive information Send impulses to the brain or spinal cord
Association Neurons Send impulses from sensory neurons to motor neurons
Motor Neurons Conduct impulses from the brain or spinal cord to muscles or glands throughout your body
Synapse Small space across which an impulse moves from an axon to the dendrites or cell body of another neuron
Synapse An impulse reaches the end of an axon Axon releases a chemical Flows across the synapse Stimulates the impulse in the dendrite of the next neuron Impulse moves from neuron to neuron
An impulse moves in only one direction across a synapse - from an axon to the dendrites or cell body of another neuron.
Reflexes Involuntary, automatic response to a stimulus Involves a simple nerve pathway called a reflex arc