central nervous system CNS
brain + spinal cord
peripheral nervous system PNS
everything else (cranial and peripheral nerves)
nervous system
the brain, spinal cord, and nerves are the organs
general function
sensory → receives stimuli via receptors
integration → relays sensory input to the CNS
motor → sends signals to the effectors that respond to the initial stimulus
the tissues comprising the nervous system are composed of neurons, supporting cells, and connective tissues. neurons are the only cells that functions in communication
nuclei of neuroglia cells
small dark purple dots
the spinal cord starts at the
foramen magnum
where it joins to the most inferior part of the brain the
medulla oblongata
cervical enlargement
here the cord is thicker because of the additional neurons needed to service the shoulder/arm
lumbar enlargement
needed to service the hip/leg
conus medullaris
cone shaped end of spinal cord
filum terminale
single, fibrous strand that attaches end of spinal cord to coccyx
meninges
brain and spinal cord enclosed in three membranes
dura mater → superficial
arachnoid matter
pia mater → deepest
CNS ‘floats’ in cerebrospinal fluid that fills the subarachnoid space
cn I
olfactory (smell)
cn II
optic (vision)
cn III
oculomotor (eye muscle, pupil constriction)
cn IV
trochlear (one extrinsic eye muscle)
cn V
trigeminal (face, nasal cavity, chewing)
cn VI
abducens (one extrinsic eye muscle)
cn VII
facial (facial expression, tears)
cn VIII
vestibulocochlear (hearing and balance)
cn IX
glossopharyngeal (taste, pressure, pain)
cn X
vagus (taste, swallowing, fullness, speech)
cn XI
accessory (soft plate, pharynx)
cn XII
hypoglossal (tongue)
brain ventricles
these are 4 cavities within the brain filled with cerebrospinal fluid (CSF)
lateral ventricles → the largest ventricle; located just below the corpus callosum
third ventricle
cerebral aqueduct
fourth ventricle
central canal
general neuron structure
1
cell body (soma)
general neuron structure
2
dendrites
general neuron structure
3
nissl bodies
general neuron structure
4
nucleus
general neuron structure
5
trigger zone
general neuron structure
5a
axon hillock
general neuron structure
5b
intitial segment
general neuron structure
6
axon
general neuron structure
7
nodes of ranvier
general neuron structure
8
schwann cells of myelin sheath
general neuron structure
9
synaptic knob
general neuron structure
10
axon collateral
giant multipolar neurons
1
nucleus
giant multipolar neurons
2
cell processes
spinal cord and spinal nerves
1
occipital bone
spinal cord and spinal nerves
2
brainstem
spinal cord and spinal nerves
3
cervical enlargement
spinal cord and spinal nerves
4
lumbar enlargement
spinal cord and spinal nerves
5
conus medullaris
spinal cord and spinal nerves
6
filum terminale
spinal cord and spinal nerves
7
cauda equina
cross section of the spinal cord
1
spinal meninges
cross section of the spinal cord
1a
dura mater
cross section of the spinal cord
1b
arachnoid mater
cross section of the spinal cord
1c
pia mater
cross section of the spinal cord
2
epidural space
cross section of the spinal cord
3
subdural space
cross section of the spinal cord
4
subarachnoid space
cross section of the spinal cord
5
spinal nerve
cross section of the spinal cord
6
dorsal root ganglion
cross section of the spinal cord
7
dorsal root
cross section of the spinal cord
8
ventral root
cross section of the spinal cord
9
white matter
cross section of the spinal cord
10
gray matter
cross section of the spinal cord
11
vertebral artery
cross section of the spinal cord
12
dorsal horn of gray matter
cross section of the spinal cord
13
lateral horn of gray matter
cross section of the spinal cord
14
ventral horn of gray matter
cross section of the spinal cord
15
gray commissure
cross section of the spinal cord
16
central canal
cross section of the spinal cord
17
anterior median nerve
cross section of the spinal cord
18
sympathetic chain ganglia
nervous tissue histology
1
white matter
nervous tissue histology
2
dorsal horn
nervous tissue histology
3
ventral horn
nervous tissue histology
4
gray commissure
nervous tissue histology
5
central canal
brain structures
1
gyri (sing. gyrus)
brain structures
2
sulci (sing. sulcus)
brain structures
3
central sulcus
brain structures
4
lateral horn
brain structures
5
frontal lobe
brain structures
6
parietal lobe
brain structures
7
occipital lobe
brain structures
8
temporal lobe
brain structures
9
cerebellum
brain structures
10
brain stem
brain structures
10a
pons
brain structures
10b
medulla oblongata
brain structures
11
spinal cord
cerebral hemispheres
1
central sulcus
cerebral hemispheres
2
longitudinal fissure
cerebral hemispheres
3
frontal lobe
cerebral hemispheres
4
parietal lobe
cerebral hemispheres
5
occipital lobe
cerebral hemispheres
6
temporal lobe
cerebral hemispheres
7
pons
cerebral hemispheres
8
medulla oblongata
cerebral hemispheres
9
cerebellum
cerebral hemispheres
10
olfactory bulbs of the olfactory nerve (CN I)
cerebral hemispheres
11
olfactory tracts of CN I
cerebral hemispheres
12
pituitary gland
cerebral hemispheres
13
optic chiasm and optic nerve (CN II)
sagittal section
1
cerebral cortex (gray matter)
sagittal section
2
gyrus