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
What is the function of microglia?
(Modified immune cells) act as scavengers
(Bc microglia, so microbe, so they say to the microbe get outta hea)
What is the function of ependymal cells?
create barriers between compartments (append something new)
source of neural stem cells. (append something where there was nothing)
What forms the myelin sheath in the CNS and PNS?
It is formed by Schwann
cells in the PNS and
oligodendrocytes in the CNS.
What structure is the brain inclosed in?
cranium (Skull)
What are the three parts of the brain?
cerebrum, cerebellum, and brain stem.
What is the cortex? What is it composed of?
The outer part of
the cerebral hemispheres and is
composed of gray matter.
.
.
(Like cork, and cork is usually on the outer most part of an oil bottle)
What is the gray matter in the cortex?
nerve cell bodies, dendrites, and neuroglia
What is the interior part of the cerebral hemispheres called?
white matter. made of:
.
axons (myelin)
.
ventricles filled with cerebrospinal fluid (CSF).
What type of enlargements does the spinal cord have?What do they supply?
Cervical: nerve supply for upper limbs
.
Lumbar: nerve supply for lower limbs
.
.
.
(Makes sense since the lumbar is down)
Where is the grey and white matter located in the spinal cord?
Grey: centrally located (inside)
White: perphirally located (outside)
What is the ending of the spinal cord called?Where does it end in adults and newborns?
It ends at: Conus medullaris
adults: L1-L2
Newborns:L3
Where are GSE – motor neurons located? (1)
Ventral horn
(bc bc motors have vents which the noise from the horns pass)
Where are GVE - preganglionic sympathetic located? (2)
lateral horn
(lateral, like illiterate so pre )
Where are GSA & GVA – sensory neurons located? (3)
dorsal root ganglion
(bc roots are sensory)
What are the three layers of meninges?
Pia mater (looks like pie)
.
Arachnoid mater (the mater under it look like spider webs)
.
Dura mater (remember the translation in arabic)
What is the function of meninges?
They surround and protect
the brain and spinal cord.
What is the subarchanoid matter?
They contain the
subarachnoid space, which is the interval between the arachnoid and pia mater, filled with CSF.
Where do motor and sensory fibers of the cranial send signals and where are their cell bodies located?
- Motor fibers that carry signals from the central nervous system (CNS) to the muscles and glands. The cell bodies of these motor fibers are located inside the CNS.
- Sensory fibers that carry signals from the body to the CNS. The cell bodies of these sensory fibers are located in clusters called sensory ganglia, which are found outside the CNS.
where do the cranial nerves emerge?
Emerge from the ventral aspect of
the brain (except for the trochlear nerve, cranial nerve IV).
What is the CN I
olfactory nerve
(bc you have one nose)
What is the CN II
optic nerve
(bc you have II eyes)
What is the CN III
Oculomotor nerve (muscles of the eye)
What is the CN IV
Trochlear nerve (muscles of the eye)
What is the CN V
Trigeminal nerve (chewing muscles, skin of the face)
What is the CN VI
** Abducens nerve (muscles of the eye)**
What is the CN VII
Facial nerve (muscles of facial expression, taste sensation, and
salivary glands)
What is the CN VIII
Vestibulocochlear nerve (hearing and balance)
What is the CN IX
Glossopharyngeal nerve (parotid gland and senses from post. 1/3
of the tongue)
What is the CN X
Vagus (involved in swallowing, regulating heart rate, breathing,
and digestion)
What is the CN XI
Accessory nerve (sternocleidomastoid and trapezius muscles)
What is the CN XII
Hypoglossal nerve (muscles of the tongue)
What are the types of ganglia?
Sensory and autonomic
What do sensory ganglia contain?
contain cell bodies of either pseudounipolar or bipolar sensory neurons
What do Autonomic ganglia contain?
contain postganglionic autonomic (sympathetic or parasympathetic) neurons
What do spinal nerves consist of?
Consist of 31 pairs: 8 cervical, 12
thoracic, 5 lumbar, 5 sacral, and 1 coccygeal.
