lecture 8 Flashcards
organization of the nervous system
what are the function of the nervous system?
sensory, integrative, and motor functions
what is the significance of the named functions of the nervous system?
they provide the nervous system with the ability to rapidly maintain homeostasis
how is the nervous system divided?
central nervous system and peripheral nervous system
how is the central nervous system divided?
into the brain (duramater, arachnoid mater, pia mater) and spinal cord
how is the peripheral nervous system divided?
these are everything outside the dura mater and comprise of:
sensory receptors (mechanoreceptors, pain and temperature receptors)
peripheral portions of the spinal and cranial nerves
the peripheral portions of the autonomic nervous system
what kind of muscle is generally affected by the somatic motor neuron?
striated muscle (skeletal) which goes from the cell body in the CNS to the effector (muscle) via axon
what is involved in the transmission of signals involving the autonomic nervous system for the neuron?
two neurons involved, we see this from the preganglionic axon from the brain or spinal cord and then forms connection with autonomic ganglion which then sends signal to the muscle or gland via post ganglionic axon
what are the cells of the nervous system?
neurons and neuroglia
what are the characteristics of neurons?
they vary in morphology, conduct impulses from one part of the body to another, and they have specialized regions of the neuron that allow for unidirectional flow of information, very fine control over the information and allows for the information to be very specific
what do dendrites do?
carry information to the cell body
what do axons do?
carry information away from the body
axons can only be myelinated, T/F?
false, they can also be unmyelinated
the peripheral only has afferent neurons, T/F?
false, it has both afferent and efferent neurons
what are the layers of the peripheral nerve?
epineurium (outer layer covering whole bundle) > Perineurium (covers individual bundles) > within the bundle you have the endoneurium
what is the sheath in the CNS called that covers the axon? for the PNS?
myelin sheath; Schwann cells that serve as the myelin sheath for the axons
if we say the neuron is sensory is it afferent or efferent?
afferent
if we say the neuron is motor, is it afferent or efferent?
efferent
what is the thalamus?
relay center between peripheral system and brain; dense cell body
what is the hypothalamus?
median eminence communicating with pituitary gland
what is significant about the grey matter?
neuron cell bodies, lower motor neurons because upper motor neurons are in the cerebral cortex
what is significant about the white matter?
neuronal axons or pathways that collect information from the periphery and send signal to CNS (afferent) or efferent
why is there more white matter than grey matter in the cervical than sacral?
because pathways sending signals occur most often in the upper portions of the vertebrae and as you go descend down the vertebrae you have more grey matter than white matter because all the signals have already happened
what are the three layers of the spinal cord?
dura mater - very thick, then arachnoid mater, finally pia mater
what is significant about the conus medullar is?
end of the spinal cord, L1-L2; they continue and branch out to form the caudal equina before they leave the bony encasement
what is the filum terminale?
end portion of the nerve
what is the fasciculus gracilis? fasciculus cuneatus?
comes from lower body and collected via proprioception, fine touch and vibration; same as the gracilis but information is collected in the upper body
what is spinothalamic tract, like where does it go? same for spinoolivary tract?
comes from spinal cord and goes to the thalamus; goes from spinal cord to the olivary nuclei
what is important to note about the lateral spinothalamic tract and the ventral spinothalamic tract in relation to the posterior column containing the fasciculus gracilis and fasciculus cuneatus?
Note that posterior columns containing the fasciculus gracilis and cuneatus (signals from upper or body like proprioception, vibration, fine touch information) affect anterolateral tracts by carrying pain and temperatures sensations upward
what does the lateral corticospinal tract do?
it takes signals from cerebral cortex (upper level neurons) and uses descending pathways to reach the motor neurons to effect muscles (lower level neurons)
what comprises the diecephalon?
thalamus and the hypothalamus
what are the secondary brain vesicles?
Telencephalon Diencephalon Mesencephalon Metencephalon Myelencephalon
- Tom and Dick Messily Met Myley (Miley) Cyrus
Name the cranial nerves
● I: Olfactory nerve ● II: Optic nerve ● III: Oculomotor nerve ● IV: Trochlear nerve ● V: Trigeminal nerve/dentist nerve ● VI: Abducens nerve ● VII: Facial nerve ● VIII: Vestibulocochlear nerve/Auditory nerve ● IX: Glossopharyngeal nerve ● X: Vagus nerve ● XI: Accessory nerve/Spinal accessory nerve ● XII: Hypoglossal nerve
Oh Oh Oh To Tickle A Female’s Vagina Gave Victor A Hard-on
what are the lobes of the brain?
● Frontal Lobe: main motor functions
● Parietal Lobe: sensory functions
● Temporal Lobe: hearing functions
● Occipital Lobe: visual
what is the motor homunculus?
how your brain sees your body, helps to determine how much motor function needs to go to that particular part of the body, facial muscles controlled with fine detail that leg muscles for example
