Chapter 8 - Neurons Flashcards
in nerve cell trigger zone is blank
the integrator
in nerve cell dendrite = blank
sensor
in nerve cell the axon and synaptic terminal are blank
effector
resting membrane potential is determined by these two things
K+ concentration gradient, membrane permeability to K+ Na+ and Cl-
channel types vary in these two things
threshold (minimum stimulus required to open), speed of opening/closing
differences between action potentials and graded potentials
graded potentials have variable strength, short distances because use diffusion
whereas action potentials are all or none events, and travel long distances
graded potentials occur in blank and blank
dendrites, soma
in graded potentials, signal strength is proportional to blank
stimulus strength
graded potentials move by blank
diffusion
graded potentials decrease in blank as they blank from origin
strength, spread
trigger zone is the blank
high concentration of voltage gated ion channels
sodium and potassium channels have the same blank but differ in their blank
threshold, speed of opening/closing
axon hillock is where
soma meets axon
two gates of voltage gated ion channels
activatino, inactivation
activation gate is blank at rest whereas inactivation gate is blank at rest
closed, open
if activation gate is opened then a blank occurs
action potential
period where there is no way to have another action potential
refractory period
refractory period where only the Na+ activation gate is closed
absolute
refractory period where both Na+ gates are reset
relative
it is possible but difficult to create another action potential during relative refractory period because
potassium ions are still moving out so sodium would have to outdo those ions to create a new action potential
two things that affect the speed of action potential in neuron
diameter of axon, resistance of membrane
larger axon diameter equals blank diffusion
faster
more resistance of leaking of a membrane causes blank diffusion
faster
myelin helps with membrane blank
resistance
two types of conduction in axons
continuous, saltatory
this conduction is when every section of the membrane must be depolarized
continuous
only nodes of Ranvier are depolarized and is faster conduction because the signal is insulated
saltatory conduction
two types of synapse
chemical, electrical
chemical synapses flow in blank directions and is blank or blank such as blank
one, inhibitory, excitatory, neurotransmitters
synapses where electrical signals via gap junctions and there is blank direction flow and the pre and post respond blnak
two, the same, electrical synapses
ach must bind to a receptor because it is blank
lipophobic
choline is recycled in a synapse in order to prevent blank
running out of neurotransmitter
two cholinergic receptors
nicotinic, muscarinic
cholinergic receptor on skeletal muscle, in PNS and CNS
nicotinic
cholinergic receptor in PNS only
muscarinic
nicotinic are blank cation channels for these two things
monovalent, Na+, K+
nicotinic receptors are usually blank because they blank membrane membrane potential
excitatory, depolarize
nicotine is a powerful blank
agonist
muscarinic receptor is a blank receptor
G protein coupled
muscarinic receptor can be blank or blank
excitatory (depolarize) or inhibitory (hyperpolarize)
muscarine is a powerful blank toxin and blank
fungal, agonist
nicotinic receptor is blank than muscarinic but muscarinic is blank
faster, longer lasting
nicotinic receptors are in what divisions of ANS
parasympathetic, sympathetic
muscarinic receptors are in what divisions of ANS
parasympathetic… smooth muscles
two types of adrenergic receptors
alphas, betas
adrenergic receptor that binds norepinephrine more than epinephrine
alphas
alphas are blank with blank as the second messenger
G protein receptors, IP3
alphas generally blank activity and blood flow
decrease
adrenergic receptor that binds norepinephrine more than epinephrine
betas
betas are blank receptors with blank as a second messenger
G protein, cAMP
betas generally blank activity and blood flow
increases
receptors generate blank potentials
graded
two types of potentials that receptors produce
excitatory graded, inhibitory graded
excitatory graded potentials blank membrane potential and blank chance of potential
depolarize, increase
inhibitory graded potentials blank membrane potential and blank chance of potential
hyperpolarize, decrease
neural pool that causes amplification and has diverse responses
divergence
neural pool that exhibits redundancy to duplicate response and integrates inhibitory graded potentials as well as excitatory
convergence
redundancy is aka
spatial redundancy
these bind to inhibitory receptors and cause an action potential to not be fired in times of stress
endorphins
repeated subthreshold excitatory graded potentials from the same presynaptic neurons
facilitation
results from graded potentials coming from different points in space
spatial summation
results from graded potentials coming from same point at different times
graded potentiasl
up regulation of receptors and increased stores and secretion (cytoskeleton) of neurotransmitter
potentiation
down regulation of receptors and change receptor isoforms
depression
examination of a sample of glandular cells reveals an extensive network of rough ER. which of the following would be a likely product?
a. digestive enzymes
b. steroid hormones
c. peptide hormones
d. antibodies
c. because rough er has ribosomes which create proteins
a. because most enzymes are proteins which are made by rough er ribosomes
d. because antibodies are proteins which are made by rough er ribosomes
when administered together , glucagon and cortisol cause greater blood glucose than their individual effects combined, this is an example of:
a. synergism
b. permissiveness
c. antagoniism
a. because they are being added together which multiplies their individual effects
an isolated cell is unable to manufacture proteins required for the ETC; which is correct:
a. it will function normally
b. it will function for a short time and then die
c. it will always have reduced function
d. the cell will die immediately
b. because it will just make a lot less ATP and eventually will run out of energy
ghrh from hypothalamus –> gh from anterior pituitary –> igf from liver; assuming ghrh binds to a G protein coupled receptor, what effect would increase cAMP in anterior pituitary cells have on secretion of all 3 hormones?
increase igf, decrease ghrh, increase gh…. draw it… six points
