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Nervous System Everardo Juarez P.2 - Coggle Diagram
Nervous System Everardo Juarez P.2
Major divisions and subdivisions of the nervous system
Central nervous system (CNS):
Made up of the brain and spinal cord.
• Responsible for integration of information and decision-making.
Peripheral nervous system (PNS):
Made up of cranial and spinal nerves that connect the CNS to the rest of the body.
Contains sensory (afferent) and motor (efferent) divisions
Motor functions:
• Somatic nervous system: controls voluntary skeletal muscles.
• Autonomic nervous system: controls involuntary effectors (smooth and
cardiac muscles and glands).
Major Functions of the nervous system
motor output (response)
Nerve impulses (CNS) are conducted along motor neurons to
effectors.
Effectors are muscles or glands that respond to decisions made in the
CNS
integration and
processing (decision-making)
• Coordination of sensory information in the CNS.
• Processing of this information is the basis for decision-making.
sensory input
Provided by sensory receptors, which detect internal or external
changes.
information travels from receptors to sensory neurons, which
transport information into the CNS.
Neurotransmitters
Neurotransmitters are the chemical messengers in a synapse, that convey an electrical impulse from a neuron to another cell.
. Reflex arc
Disorders/Diseases
Drugs of abuse
Cranial nerves
Connective Tissue Coverings
Spinal nerves
Major parts and functions of the brain
Major parts and functions of the spinal cord
Action potential & the Nerve Impulse
Compare & contrast the autonomic nervous system
Classification of neurons
A neuron contains a cell body, tubular cytoplasm-filled dendrites, and a tubular, cytoplasm-filled axon.
The cell body (soma) contains major organelles including nucleus.
Dendrites conduct impulses toward the cell body; they are short and branching, and they provide the receptive surface for communication with other neurons
The axon conducts impulses away from the cell body; it arises from a thickening extending from the cell body, called the axon hillock
There is only 1 axon in each neuron.
Structural Classification of Neurons
Neurons differ in size, shape, and structure:
• Multipolar neurons: have many dendrites and one axon arising from their cell bodies; most neurons with cell bodies in CNS (interneurons and motor neurons) are multipolar.
• Bipolar neurons have 2 processes extending from the cell body, adendrite and an axon; found in some of the special senses, such as the eyes, nose, and ears.
Unipolar neurons have only 1 process extending from the cell body; outside the cell body, it soon splits into 2 parts that function as 1 axon; the peripheral process has dendrites near a peripheral body part, and the central process runs into the CNS; the cell bodies are found in ganglia outside the CNS; these are sensory neurons.
Functional Classification of Neurons 1
Sensory (afferent) neurons: conduct impulses from peripheral
receptors to the CNS; usually unipolar, although some are bipolar.
Interneurons (association or internuncial neurons): multipolar
neurons lying within the CNS that form links between other
neurons; the cell bodies of some interneurons aggregate in
specialized masses called nuclei.
Motor (efferent) neurons: multipolar neurons that conduct
impulses from the CNS to peripheral effectors (muscles or glands).
tissues
Neurons: cells that communicate, via electrical impulses, with other neurons or other tissues
Neuroglia: cells that support, nourish, protect, and insulate
neurons