OT 342 Handout 1
Astrocyte function (3) ______ : remove neuronal debris and following injury (so sounds like cleaning Look at lecture for this part)
Scavengers
Glial cells roles (3) : ______ : remove neuronal debris and following injury (so sounds like cleaning Look at lecture for this part)
Scavengers
This is. _____ cells: provide myelin in the peripheral nervous system. each ____ cell provides one covering of the myelin along the axon. So ____ cell wrap around the axon
Schwann
The cell body has _____ volume of the cell (responsible for keeping the cell body alive and giving it lipids)
10%
cell body represents ____ cell's total volume?
10%
Although nerve cells can be classified into perhaps as many as ______ different types, they nevertheless share many common features.
10,0000
There are between ____ times more glial cells than neurons in the CNS of vertebrates.
10- 50
The best estimate is that the human brain contains about _____ neurons
100 billion
A typical neuron would go _____ . This would represent a football field going from one side to another in one second speed is important
120m/sec
Length: ____ in length for an axon. (Ex: so when I abduct my adductor pollicus longus (thumb), the signal starts in the brain and travels down to the spinal cord and goes to the spinal motor neurons and that singular neuron goes from spinal cord to ventral horn to activate muscle in adductor pollicus longus, this is ____ in length)
1m
This is ____ : Sensory neurons that carry information (action potential) to the central nervous system
Afferent
This is ______ : provide 1,3,4,5,6,7 all of those functions (are capable of replication so they can multiply ). Most tumors in the brain are known as ______ proliferatin (increase in numbers) i) Cell body (Soma or perikaryon) has the rough endoplasmic reticulum and smooth endoplasmic reticulum metabolic center of the nerve 10% volume of the cell (responsible for keeping the cell body alive and giving it lipids) ii) Dendrites (Greek word= tree) merge off the cell body receptive portion of the neuron where one neuron communicates with another neuron (where information is passed on) one neuron will give chemical information to the next neuron iii) Axon (known as the conducting element) information is conducted to different portions of the central nervous system (sends info) range from 0.2-20 microns in diameter and they are often surrounded by myelin and myelin covering increases the conduction velocity and speed Length 1m in length for an axon. (Ex: so when I abduct my adductor pollicus longus (thumb), the signal starts in the brain and travels down to the spinal cord and goes to the spinal motor neurons and that singular neuron goes from spinal cord to ventral horn to activate muscle in adductor pollicus longus, this is 1m in length) 120m/sec would represent a football field going from one side to another in one second speed is important iv) Presynaptic terminal transmitting element of the nerve-> where one neuron will transmit activity to a muscle or to another nerve that most of them release a chemical so there is a chemical transmission so presynaptic terminal most of the time is a chemical transmission which is excitatory (which can lead to activation and fire up a nerve ) or inhibitory (or stop or slow down a nerve)
Astrocytes:
This is. ____ neurons and it is two neurites coming off the cell body
Bi (two) polar
Muscle Stretch Reflex: Step 1 As the muslces become longer, the quadriceps send a signal to the nervous system about the length of the muscle. And we have different receptors that send signal to the ____ about what is happening in the periphery •
CNS
Muscle Stretch Reflex: Step 5 After a neuron innervates the quadriceps muscle, the information will travel from the ______ to PERIPHERNAL NERVOUS SYTEM and will lead to activation of the muscle being stretched.
CNS
The metabolic center of the nerve is the _____
Cell body
This is. _____ : motor neurons carry information (action potential) away from the central nervous system to the peripheral nervous system
Efferent
_______ (or also known as neuroglia): non excitable cells and these cells only have a resting state so they are only support cells for the central nervous system 40x more glial cells than nerve cells
Glial cell
____ responsible for fast anterograde axonal transport
Kinesin
Glial cells are based on their size: ____ (Bear, p 49): larger cells
Macroglia
Glial cells are based on their size: _____ (Bear, p 52): very tiny cells and act as immune system of the nervous system: mobilized (moved) after injury/disease/infection
Microglia
motor nerve makes contact with muscle cell which leads to activation of the muscle, this is ____
Motor end plate
Muscle Stretch Reflex: Step 2 • ______ regulates and informs CNS about the length of the muscle so when you hit the tendon with the reflex,the muscle is stretched and signal is given back to the nervous system (central) and this makes contact with a different neuron
Muscle spindle
This is. _____ Doctrine: The neurons are the basic signaling unit of the nervous system and each neuron is a discretely (lowkey) bound cell
Neuron
Glial cells roles (7) : _____ function - break down food into nutrients. The body uses the nutrients for energy, growth, and cell repair
Nutritive
This is ______ : form myelin in the central nervous system and once cell can give up to 15 neurons
Oligodendrocytes
Muscle Stretch Reflex: Step 5 After a neuron innervates the quadriceps muscle, the information will travel from the CNS to ____ and will lead to activation of the muscle being stretched.
PERIPHERNAL NERVOUS SYTEM
Muscle Stretch Reflex: Step 3 • _____ information is carried and generates an action potential and communication that occurs within the muscle spindle. This leads to an action potential which is generated to the central nervous system.
Peripheral
This is a __ cell are considered a bipolar cell but eventuallly form this single neurite in the cell body . With the maturation of the fetus, the cell migrates to the dorsal root ganglion.
Pseudo-unipolar
_______ neuron goes to central to periphery to activate the muscle and innervate muscle fibers.
Spinal motor
Astrocyte function (1) _______-provide firmness and structure to the brain
Supporting element
Glial cells roles (1): _______-provide firmness and structure to the brain
Supporting element
This is. _____ cells : one neuron that comes off -> single neurite not common in mammals a type of neuron in which only one neurite) extends from the cell body. (singe cell body with one neuron) Rare in mammals and are found in some ganglia
Unipolar
Muscle Stretch Reflex: Step 3 • Peripheral information is carried and generates an _____ and that occurs within the muscle spindle. This leads to an ______ which is given to the central nervous system.
action potential
Information sent to the central nervous system is _____ information. Nerve will carry that information to become an efferent neuron.
afferent
This is interneurons: Largest class of nerves and these carry information between _____ and efferent nerves.
afferent
_____ cells roles (5) : During development, ____ cells will guide the migration of neurons (provide the guiding of neurons so that neurons can go to their contact)
astrocyte
Afferent and efferent neurons have in common: both have cell body, dendrites/synapses, contact, _____, and both have terminate part to communicate with additional cells.
axon
Dynamic polarization of neurons: flow of information: dendrites to the _____ to the terminal area
axon
This is ____ (known as the conducting element) information is conducted to different portions of the central nervous system (sends info)
axon
Astrocyte function (6) : Cells that form the ______ barrier so that not everything that is in our blood stream makes it into the central nervous system
blood brain
Glial cells roles (6) : Cells that form the ______ barrier so that not everything that is in our blood stream makes it into the central nervous system
blood brain
Astrocyte cells roles (4) : _____ (absorb )ions and neurotransmitters when you change concentration gradient you can change the resting state Astrocyte cells will ______ ions to maintain concentration gradient inside and outside of the cell
buffer
Glial cells roles (4) : _____ (absorb )ions and neurotransmitters when you change concentration gradient you can change the resting state glial cells will ______ ions to maintain concentration gradient inside and outside of the cell
buffer
Afferent and efferent neurons have in common: both have a ____ dendrites/synapses, contact, axon, and both have terminate part to communicate with additional cells.
cell body,
afferent: sensory neurons that carry information (action potential) to the ______ system
central nervous system
Afferent and efferent neurons have in common: both have cell body, dendrites/synapses, ____, axon, and both have terminate part to communicate with additional cells.
contact
Efferent carries information from the central nervous system to the periphery and this leads to _____ of the muscle. Efferent leads to inhibtion (restricting) of the antagonist muscle
contraction
receptive portion of the neuron where one neuron communicates with another neuron (where information is passed on) one neuron will give chemical information to the next neuron, this is done through the ____
dendrites
Afferent and efferent neurons have in common: both have cell body, ______, contact, axon, and both have terminate part to communicate with additional cells.
dendrites/synapses
Astrocytes serve the following functions with the exception of: a. buffering function by taking up certain neurotransmitters from the synaptic area b. nutritive function c. buffering function by taking up excess potassium released during high activity d. act as scavengers and remove neuronal debris e. none of the above since all are functions of astrocytes
e . none of the above since all are functions of astrocytes
Muscle Stretch Reflex: Step 8 The anatagonist muscle (hamstring) is deactivated and will cause relaxation so when you get an extension of the muscle during the ____, you want to make sure the hamstrings are _____
relaxed
Spinal motor neuron are _____ neuron and is multipolar neuron and cell body is located in the ventral horn and receives input (8000 dendrite) 10,000 soma
efferent
This is interneurons: Largest class of nerves and these carry information between afferent and _____ nerves
efferent
Neurons are the functional units of the nervous system and differ from most other cells in the body in being _____
excitable
Glial cells are non -____. (do not generate an action potential)
excitatory
presynaptic terminal most of the time is a chemical transmission which is _____ (which can lead to activation and fire up a nerve ) or inhibitory (or stop or slow down a nerve)
excitatory
Muscle Stretch Reflex: Step 6 The muscle being stretched will contract to resist the stretch and now you get the ____ of the limb.. This leads to the patellar reflex
extension
Muscle Stretch Reflex: Step 8 The anatagonist muscle (hamstring) is deactivated and will cause relaxation so when you get an ____ of the muscle during the patellar reflex, you want to make sure the hamstrings are relaxed
extension
Microtubules are the essential stationary tract used for ____- transport and ___ transport
fast retrograde transport and fast anterograde axonal transport
Neurons can also be further classified ____ into three major groups:
functionally
_____ cells roles (5) : During development, ____ cells will guide the migration of neurons (provide the guiding of neurons so that neurons can go to their contact)
glial
GLIAL CELLS: (read Bear, pages 49 - 52) Nerve cell bodies and axons are surrounded by glial cells (Greek glia = "____") (help neurons to carry out their function
glue
Muscle Stretch Reflex: Step 7 The patellar reflex leads to inactivation (not working) of the antagonist muscle (_____: semitendinosus, semimembranosus, tibia).
hamstring
This is afferent: ____ neurons that carry information (action potential) to the central nervous system
sensory
Principle of connection specificity (2nd rule) Nerve cells do not connect in _____
indiscriminaity.
presynaptic terminal most of the time is a chemical transmission which is excitatory (which can lead to activation and fire up a nerve ) or _____ (or stop or slow down a nerve)
inhibitory
This is ____: Largest class of nerves and these carry information between afferent and efferent nerves.
interneurons
This is. efferent :_____ neurons carry information (action potential) away from the central nervous system to the peripheral nervous system
motor
Spinal motor neuron are efferent neuron and is _____ neuron and cell body is located in the ventral horn and receives input (8000 dendrite) 10,000 soma
multipolar
This is a _____ Neurons: multiple neurites that come off the cell body
multipolar
Somatic efferent (motor neurons) fibers are classified as:
multipolar cells
Glial cells roles (2): Form ____ (_____ is an insulating sheath that covers the axon and _____ allows a nerve to conduct at a rapid speed) Glial cells that form the ____ and this surrounds the axon to increase the conducting speed. Rapidity is important for the communication between the nervous system. (ex: if you were touching a hot kettle, and if your nerves aren't fast, you wouldn't realize you are touching something really hot fast and your hand would be burned or damaged but because we have fast nerves, we are able to detect the pain quickly and react to it so we don't get hrut
myelin
_____ covering increases the conduction velocity and speed
myelin
excitable cells (so_____ are the one that genereate action potentials _____ means that they can change their membrane potential to cause an Action potential. Action potential is used to give communication from one part of the nerve to another
nerve cells
Muscle Stretch Reflex: Step 4 The signal from the action potential will communicate with a different neuron and a second _____ will go and innervate the muscle
neuron
Muscle Stretch Reflex: Step 6 The muscle being stretched will contract to resist the stretch and now you get the extension of the limb.. This leads to the ______
patellar reflex
Muscle Stretch Reflex: Step 7 The ______ leads to inactivation (not working) of the antagonist muscle (hamstring: semitendinosus, semimembranosus, tibia).
patellar reflex
Muscle Stretch Reflex: Step 8 The anatagonist muscle (hamstring) is deactivated and will cause relaxation so when you get an extension of the muscle during the ____, you want to make sure the hamstrings are relaxed
patellar reflex
This is. efferent :motor neurons carry information (action potential) away from the central nervous system to the______
peripheral nervous system
Efferent carries information from the central nervous system to the _____ and this leads to contraction of the muscle
periphery
This is Principle of dynamic _____ : Flow of information within the central nervous system is very precise and will flow from the dendrites to the axon to the terminal area and not from terminal area to axon
polarization
An important point is that nerve cells with basically similar properties are able to produce very different actions because of ______ connections with each other and with sensory receptors and muscle.
precise/specific
This is a ______ : transmitting element of the nerve-> where one neuron will transmit activity to a muscle or to another nerve
presynaptic terminal
Mature neurons do not undergo ______ (grow in numbers) . Therefore, most disease processes that affect neurons are associated with neuronal degradation and loss. (so when neurons die they are not replaced in the mature central nervous system)
proliferation
Muscle Stretch Reflex: Step 8 The anatagonist muscle (hamstring) is deactivated and will cause_____ so when you get an extension of the muscle during the patellar reflex, you want to make sure the hamstrings are relaxed
relaxation
Neuronal differentiation: The feature that most dramatically distinguishes one neuron from another is _____ , specifically the number and form of a neurons processes (neurties number of processes that emerge from the given cell body)
shape
Muscle Stretch Reflex: Step 1 • As someone knocks into the tendon, the quadriceps ______ so the patellar tap leads to a _____ of the muscle.
stretching
Principle of connection specificity (3rd rule) Each nerve makes specific connections at precise points of _____ For example: In spinal tap reflex, if we follow, the afferent nerve makes a PRECISE connection with the efferent nerve that goes back to the muscle of origin. (VERY PRECISE)
synaptic contact
Dynamic polarization of neurons: flow of information: dendrites to the axon to the _____
terminal area
