Pack Flashcards
What is the central nervous system composed of
The brain and spinal cord
What is the peripheral nervous system composed of
Cranial nerves and spinal nerves
What is the peripheral nervous system further divided into
autonomic and somatic nervous systems
What is the somatic nervous system composed of
sensory (afferent) and motor (efferent)
(if you remove all organs except skin, whatever is left the somatic nervous system controls it)
(Sensory is afferent bc a is before e and you need to sense something before firing the motor neuron.)
What is the autonomic nervous system composed of
sympathetic and parasympathetic
How many pairs of cranial nerves and spinal nerves does the peripheral nervous system have
12 pairs of cranial nerves
31 pairs of spinal nerves
What type of cells is the nervous system composed of?
The nervous system is composed of
neurons and neuroglia cells
(astrocytes, oligodendrocytes, ependymal cells, and microglia).
What are neurons?
Neurons are the structural and
functional units of the nervous system.
What is the function of neurons
They specialize in the reception,
integration, transformation, and transmission of information
how many neurons and glial cells does the human brain have?
The human brain contains
approximately 86 billion neurons and 85 billion glial cells
Where are cell bodies located in the CNS?
Cell bodies are located in the gray
matter of the CNS
what are the collections of cell bodies called in the PNS
ganglia
what are the collections of cell bodies called in the CNS
nuclei
(Nuclei, so CNS )
What are the classifcations of neurons?
Bipolar
Pseudounipolar
Multipolar
what are bipolar neurons? Where are they found? What is their function?
They have two branches, one of them is an axon, and the other is a dendrite. They are sensory and are found in:
olfactory epithelium, the retina, and the inner ear.
what are Pseudounipolar neurons?Where are they found? What is their function?
They have only one process, (only an axon) but it branches into two axons, (The peripheral and central) one of which acts as a dendrite (peripheral).
They are sensory neurons of the PNS and are found in the spinal and cranial nerve ganglia.
what are multipolar neurons?
“The steryotypical neuron”; has one axon and multiple dendrites and is most common in the CNS. (NOT a sensory neuron)
Examples:
motor cells in anterior and lateral horns of the spinal cord and autonomic ganglion cells
what is the function of somatamotor neurons (GSE)?
conduct impulses to skeletal muscles of the body and they are found in anterior horns of the spinal cord or motor nuclei of cranial nerves.
what is the function of Visceromotor (GVE) neurons? What are their types?
Visceromotor (GVE) conduct impulses to glands, blood vessels, and smooth muscles.
Preganglionic sympathetic are found in the lateral horn of the spinal cord (IML in T1-L2) and postganglionic in the sympathetic ganglia.
Preganglionic parasympathetic are located in parasympathetic nuclei of cranial nerves and sacral parasympathetic n. of the spinal cord (S2-S4). Postganglionic neurons are found in parasympathetic ganglia.
What are the functions of the Somatosensory and viscerosensory neurons
receive
stimuli from the external and internal environment (spinal or cranial nerves ganglion cells).
What are interneurons?
interconnect motor or
sensory neurons within the central nervous system.
(from the name.)
What is the function of oligodendrocytes?
form Myelin sheaths
(Bc oligodendrocytes, and myelin sheaths look like lego pieces attached to the axon)
What are the functions of astrocytes?
form: support for central nervous system (like astroboy, so support)
Help form: blood brain barrier (like astroboy)
secrete: neurotrophic factors
take up: k+ neurotransmitters