The basic functional units of the nervous system are individual cells and are specialized cells that react to physical and chemical changes occurring in their surroundings.
NEUROGLIA ( glial cells )
separate and protect the neurons and provide a supportive framework for neural tissue and are primarily conentive tissue that protect and hold neurons in place
2 MAJOR ANATOMICAL DIVISIONS OF THE NERVOUS SYSTEM
Central Nervous System (CNS) and Peripheral Nervous System (PNS)
2 PRIMARY TYPES OF CELLS
Neurons and Neuroglia
Groups of peripheral nerve fibers, or axons, which are bundled together like strands of a cable
3 TYPES OF NEURONS
Sensory Neurons, Motor Neurons, and Interneurons.
SENSORY NEURONS (Afferent)
Carry impulses from the BODY to the BRAIN and SPINAL CORD
MOTOR NEURONS (Efferent)
Originate in the central nervous system and carry impulses from the CENTRAL NERVOUS SYSTEM to EFFECTOR ORGANS--usually to incite a response
Carry impulses from SENSORY NEURONS to MOTOR NEURONS
Nerve fiber with a slender cylindrical process and smooth surfaces. Transmits impulses AWAY from the cell body and carries substane to other parts of the cell.
Contains the nucleus, provides structure to the neuron, and is the METABOLIC GENETIC CENTER of the neuron.
Contain Nerve fiber and are usually short and highly branched. Possess-thornlike spines called dentritic spines.
RECEIVE impules from other cells and relay them to the cell body.
Main receptor surfaces on the neuron, where impules from the other neurons communicateto these receptive surfaces.
PROTECTIVE covering, or insulation, for the AXON and is made up of LIPIDS and PROTEIN. Also regulates the speed of impulse conduction along the axon
Specialized site where the neuron COMMUNICATES WITH ANOTHER CELL
3 PARTS OF A SYNAPSE
Presynaptic Knob, Synapti Cleft, Postsynaptic Neuron(muscle/gland).
Side of ORIGINATING impulse and is responsible and is responsible for sending a message
GAP between the presynaptic knob and the postsynaptic neuron and plays an important role in neurotransmission
RECEIVING side of the impulse and acts to continue the nerve impulse until the process reaches its end state.
CLUSTER of neuronal cell bodies located in the PERIPHERAL NERVOUS SYSTEM, and is classified as either pre-ganglionic or post-ganglionic.
The neurons that EMERGE from the BRAIN or SPINAL CORD and travel to the GANGLION
The neurons that TRAVEL AWAY from the GANGLION to the SMOOTH MUSCLE,CARDIAC, OR GLANDS
Chemical substances that are produced in neurons and transmit nerve impulses across the synapse.
6 MOST COMMON NEUROTRANSMITTERS
Acetylcholine, Norepinephrine, Dopamine, Serotonin, Gamma-aminobutyric Acid(GABA), Glutamate
Process by which neurons communicate with each other and other parts of the body, such as organs,muscles, or glands.
1st MECHANISM TO STOP NEUROTRANSMISSION
Neurotransmitters may be taken into the receiving postsynaptic neuron instead of attaching to a receptor
2nd MECHANISM TO STOP NEUROTRANSMISSION
Neurotransmitters may be inactivated by enzymes(substances that induce a chemical change) in the synaptic cleft)
3rd MECHANISM TO STOP NEUROTRANSMISSION
Neurotransmitters may be absorbed into the presynaptic neuron for reuse, which is called reuptake.
SODIUM PUMP THEORY
MOVEMENT of sodium ions INTO the axon and potassium ions moving OUT of the axon.