T/F In hyperpolarization the mv levels drop more than needed before resting state is achieved?
True- Na+ and K+ pumps restore normal levels
What happens during hyperpolarization?
membrane potential drops mopre than needed
What propogates Action potential (AP)?
A disturbance of voltage moving down the length of the axon
A wave of ____ follows AP to prevent backwards movement.
The act of AP moving from one area to another to another to another is called?
Propogation of action potential
T/F Action potential is propogated when a voltage disturbance moves down the cell body?
False- the length of the axon
Action potential (AP) uses the ___ or ___ phenomenon?
All or Nothing
T/F if graded potential is strong enough it will reach the axon hillock?
If threshold is reached at the axon hillock then ____ _____ is produced?
Graded potential ____ with distance?
T/F Action potential either happens completely or not at all?
If threshold is not reached ___ happens?
New action potentials are created at the ____ _____?
T/F Action potentials move towards the cell body?
False - Away from
T/F stronger stimuli cause AP more often than weaker stimuli?
Independent of stimuli strength all ____ ____ are the same.
What 2 factors is conduction velocity dependent on?
Axon diameter Degree of myelination
T/F Axons with larger diameters have faster velocities?
The more ____ cells (myelin) the faster the velocity?
The conduction pattern along an axon with myelin is called____?
____ ____ prevent "leakage" of charge from axon and increase membrane resistance.
T/F Ion channels are only at the Nodes of Ranvier?
AP travels ___ (faster/slower) along a myelinated axon compared to an unmyelinated axon?
T?F Action potentials "skip" from node to the next node during saltatory conduction?
Why does AP travel faster along a myelinated axon compared to an unmyelinated axon?
the ion channels at the Nodes of Ranvier allow the AP to not have to open every gated channel and instead skip to the next node
An example of Homeostatic imbalance is____?
Multiple sclerosis (MS)
Multiple sclerosis is an _____ disease?
T/F If a person has MS, their immune sytem kill its Schwann cells, resulting in a loss of myelin sheaths?
MS affects ___ neurons?
T/F MS can cause uncoodination, muscle weakness, and eventual paralysis?
There are ___ groups of nerve fibers based on conduction velocity.
Nerve fibers in group A are characterized by being ____and ____?
Large diameter axons Heavily myelinated
T/F Group A nerve fibers conduct at over 300mph?
T/F Group A nerve fibers are used by the autonomic nervous system?
False - Somatic Nervous System
What muscle group do the group A fibers serve?
T/F Group B nerve fibers are not myelinated?
False- they have some, but not a lot
About how fast do group B fibers conduct?
Which nervous system uses group B fibers?
Autonomic nervous system
T/F Group B fibers are larger than Group A fibers?
False - smaller
Which group of nerve fibers has the smallest diameter?
T/F Group C fibers are used by both the Somaticand Autonomic nervous system?
False - Autonomic
How fast do Group C nerve fibers conduct?
Are group Cf fibers myelinated?
No they are not
Waht is a junction that mediates information transfer from a neuron to another neuron or to an effector cell?
T/F A synapse mediates information to affector cells?
False - Effector cells
Where are presynaptic cells located?
Before the synapse
T/F presynaptic cells hold the formed AP?
What are used at synnapse in pre-synaptic cells?
T/F post-synaptic cells are located befor the synapse?
False- after the synapse
Post-synaptic cells ___ (may/May not) form an action potential?
May form an Action potential
T/F dendrites are used at post-synaptic synapse?
What are the three type of synapse?
Electrical synapse Chemical synapse
T/F electrical synapse is bidirectional?
In electrical synapse substances can move in_____ directions?
T/F electrical synapse is fairly commmon?
False- fairly rare
Electcal synapse ______ activities?
T/F Chemical synapse use a neurotransmitter?
Chemicla synapse is ____ directional?
uni - one way
In chemical synapse presynaptic cells ____ control post- synaptic cells.
T/F Post-synaptic cells always communicate with presynaptic cells?
False - Never
Describe the chemical synapse process.
Electric signals reach axon terminal converted to chemcal signal chemical signal sent to synpatic neuron chemical signal converted to electrical signal- gated potential if it is strong enough it starts AP
How many steps are there in the chemical synapse process?
What are the steps in removing neurotransmitter from the synaptic cleft?
Re-uptake Destroyed/Degraded diffused away from synaptic cleft
T/F Emzymes can destroy neurotransmitter in order to remove it from the synaptic ceft?
What is re-uptake?
the reobsorbtion of neurotransmitter by the presynaptic terminal
Post-synaptic potential are _____ gated, not voltage sensative?
______ initiate graded potentials?
T/F In post-synaptic potentials the strength is based on the amount of neurotransmitter and time in synapse?
post-synaptic potentials can be both ____ and ____?
excitatory and inhibitory
In Excitatory postsynaptic potentials (EPSP) neurotransmitter causes ____ of postsynaptic membrane?