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Exam 2 (VPHY 3100)
Exam 2 (VPHY 3100)
652
Physiology
Undergraduate 3
09/21/2020

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Term
divisions of the peripheral nervous system
Definition
-autonomic
-somatic
Term
autonomic nervous system
Definition
controls internal activities of organs and glands
Term
somatic nervous system
Definition
controls external actions of skin and muscles
Term
divisions of the autonomic nervous system
Definition
-sympathetic
-parasympathetic
Term
sympathetic ANS
Definition
arousing
Term
parasympathetic ANS
Definition
calming
Term
some types of nerves in the nervous system
Definition
-spinal nerves
-cranial nerves
Term
some components of the PNS
Definition
-nerves
-ganglia
-12 pairs of cranial nerves (8 mixed, 4 sensory)
-31 pairs of spinal nerves (all mixed)
Term
cranial nerves
Definition
nerves that exit the brain and brain stem
Term
spinal nerves
Definition
nerves that exit the spinal cord
Term
"mixed" nerves
Definition
contain both sensory and motor fibers
Term
autonomic nervous system aka...
Definition
visceral nervous system
Term
the flow of information in the autonomic nervous system
Definition
[image]
Term
the effector organs for somatic motor system
Definition
Skeletal muscles
Term
the effector organs for autonomic motor system
Definition
-Cardiac muscle
-smooth muscle
-glands
Term
presence of ganglia among somatic motor system
Definition
no
Term
presence of ganglia among autonomic motor system
Definition
Cell bodies of postganglionic autonomic fibers located in paravertebral, prevertebral (collateral), and terminal ganglia
Term
Number of neurons from CNS to effector in the somatic motor system
Definition
1
Term
Number of neurons from CNS to effector in the autonomic motor system
Definition
2
Term
Type of neuromuscular junction in the somatic motor system
Definition
Specialized motor end plate
Term
Type of neuromuscular junction in the autonomic motor system
Definition
No specialization of postsynaptic membrane; all areas of smooth muscle cells contain receptor proteins for neurotransmitters
Term
Effect of nerve impulse on muscle in somatic motor system
Definition
Excitatory only
(nicotinic acetylcholine receptors (NAchRs))
Term
Effect of nerve impulse on muscle in autonomic motor system
Definition
Either excitatory or inhibitory
(G-protein-coupled receptors (GPCRs))
Term
Type of nerve fibers in the somatic motor system
Definition
Fast-conducting, thick (9–13 μm), and myelinated
Term
Type of nerve fibers in the autonomic motor system
Definition
Slow-conducting; preganglionic fibers lightly myelinated but thin (3 μm); postganglionic fibers unmyelinated and very thin (about 1.0 μm)
Term
what the autonomic nervous system controls
Definition
-Regulation of cardiac muscle, smooth muscle, and glands
-Control of “involuntary” visceral organs & blood vessels
Term
what the autonomic nervous system regulates
Definition
-cardiac muscle
-smooth muscle
-glands
Term
the central control in the autonomic nervous system
Definition
-hypothalamus
-brain stem
-spinal cord
Term
where the preganglionic neuron is
Definition
brain or spinal cord
Term
general scheme for how the autonomic nervous system is organized
Definition
[image]
Term
the presynaptic and postsynaptic neurons in the autonomic nervous system in relation to the preganglionic and postganglionic neurons
Definition
[image]
Term
both the sympathetic and parasympathetic divisions of the autonomic nervous system consists of...
Definition
-preganglionic neurons (cell bodies in the CNS)
-postganglionic neurons (cell bodies in the PNS)
Term
preganglionic neurons
Definition
cell bodies in the CNS that are part of the ANS
Term
postganglionic neurons
Definition
cell bodies in the PNS that are part of the ANS
Term
where the sympathetic and parasympathetic divisions of the ANS differ
Definition
-the origination of preganglionic fibers
-the location of autonomic ganglia
-the neurotransmitters used (to some extent, mostly in the postganglionic neurons)
Term
General functional differences between the sympathetic and parasympathetic divisions of the ANS
Definition
-“rest & digest” (parasympathetic)
-“fight or flight” (sympathetic)
Term
diagram of the general differences between the sympathetic and parasympathetic divisions of the ANS
Definition
[image]
Term
where the preganglionic cells come from in the sympathetic division of the ANS
Definition
thoracic and lumbar segments of the spinal cord
Term
where the preganglionic cells come from in the parasympathetic division of the ANS
Definition
-brain stem
-lowermost (sacral) part of the spinal cord
Term
paravertebral ganglia
Definition
the double row of sympathetic ganglia that run alongside the spinal cord
Term
prevertebral or collateral ganglia
Definition
sympathetic ganglia that are further out into the periphery than the paravertebral ganglia
Term
terminal ganglia
Definition
parasympathetic ganglia that are close to or within the target tissues
Term
the neurotransmitter released by preganglionic neurons in both the sympathetic and parasympathetic divisions
Definition
acetylcholine
Term
the neurotransmitter released by postganglionic neurons in the sympathetic division of the ANS
Definition
norepinephrine
Term
the neurotransmitter released by postganglionic neurons in the parasympathetic division of the ANS
Definition
acetylcholine
Term
the way the sympathetic chain of ganglia is set up
Definition
[image]
Term
information flows into the spinal cord through ______ roots
Definition
dorsal
Term
information flows out of the spinal cord through ______ roots
Definition
ventral
Term
A sympathetic chain of ganglia (paravertebral ganglia)
Definition
line either side of the spinal cord
Term
______ split from the spinal nerves via the white rami, wherein they enter the paravertebral ganglia. These preganglionic fibers branch.
Definition
Preganglionic axons
Term
Preganglionic axons split from the spinal nerves via the ______, wherein they enter the paravertebral ganglia. These preganglionic fibers branch.
Definition
white rami
Term
Preganglionic axons split from the spinal nerves via the white rami, wherein they enter the ______. These preganglionic fibers branch.
Definition
paravertebral ganglia
Term
Preganglionic axons split from the spinal nerves via the white rami, wherein they enter the paravertebral ganglia. These preganglionic fibers...
Definition
branch
Term
Some ______ synapse with postganglionic neurons within the sympathetic chain of ganglia; these postganglionic axons leave via the gray rami & rejoin the spinal nerves.
Definition
preganglionic fibers
Term
Some preganglionic fibers synapse with ______ within the sympathetic chain of ganglia; these postganglionic axons leave via the gray rami & rejoin the spinal nerves.
Definition
postganglionic neurons
Term
Some preganglionic fibers synapse with postganglionic neurons within the ______; these postganglionic axons leave via the gray rami & rejoin the spinal nerves.
Definition
sympathetic chain of ganglia
Term
Some preganglionic fibers synapse with postganglionic neurons within the sympathetic chain of ganglia; these postganglionic axons leave via the ______ & rejoin the spinal nerves.
Definition
gray rami
Term
Some preganglionic fibers synapse with postganglionic neurons within the sympathetic chain of ganglia; these postganglionic axons leave via the gray rami & rejoin the...
Definition
spinal nerves
Term
Some ______ simply pass through the sympathetic chain of ganglia, forming splanchnic nerves, and synapse with postganglionic neurons within collateral (prevertebral) ganglia.
Definition
preganglionic fibers
Term
Some preganglionic fibers simply pass through the ______, forming splanchnic nerves, and synapse with postganglionic neurons within collateral (prevertebral) ganglia.
Definition
sympathetic chain of ganglia
Term
Some preganglionic fibers simply pass through the sympathetic chain of ganglia, forming ______, and synapse with postganglionic neurons within collateral (prevertebral) ganglia.
Definition
splanchnic nerves
Term
Some preganglionic fibers simply pass through the sympathetic chain of ganglia, forming splanchnic nerves, and synapse with ______ within collateral (prevertebral) ganglia.
Definition
postganglionic neurons
Term
Some preganglionic fibers simply pass through the sympathetic chain of ganglia, forming splanchnic nerves, and synapse with postganglionic neurons within...
Definition
collateral (prevertebral) ganglia
Term
Some ______ innervate the adrenal medulla, causing it to secrete Epi (and Norepi) into the blood.
Definition
preganglionic fibers
Term
Some preganglionic fibers ______ the adrenal medulla, causing it to secrete Epi (and Norepi) into the blood.
Definition
innervate
Term
Some preganglionic fibers innervate the ______, causing it to secrete Epi (and Norepi) into the blood.
Definition
adrenal medulla
Term
Some preganglionic fibers innervate the adrenal medulla, causing it to...
Definition
secrete Epi (and Norepi) into the blood
Term
Mass activation
Definition
the sympathetic system is typically activated as a single unit
Term
innervate
Definition
supply (an organ or other body part) with nerves
Term
how information flows through the sympathetic motor neurons
Definition
[image]
Term
why the sympathetic chain can do mass activation (activation as a single unit)
Definition
because of the paravetebral ganglia that are so close to each other along the spinal cord
Term
in the ______ division of the autonomic nervous system, preganglionic fibers originate in the midbrain, medulla, pons, and sacral levels of the spinal cord
Definition
parasympathetic
Term
in the parasympathetic division of the autonomic nervous system, ______ fibers originate in the midbrain, medulla, pons, and sacral levels of the spinal cord
Definition
preganglionic
Term
in the parasympathetic division of the autonomic nervous system, preganglionic fibers originate in the...
Definition
midbrain, medulla, pons, and sacral levels of the spinal cord
Term
in the ______ division of the autonomic nervous system, preganglionic fibers synapse with postganglionic fibers in terminal ganglia which lie close to or within target organs
Definition
parasympathetic
Term
in the parasympathetic division of the autonomic nervous system, preganglionic fibers synapse with postganglionic fibers in...
Definition
terminal ganglia which lie close to or within target organs
Term
Most parasympathetic fibers (are or are not) bundled within spinal nerves
Definition
are not
Term
cutaneous effectors & blood vessels associated with skeletal muscle (are or are not) parasympathetically-innervated
Definition
are not
Term
______ carry parasympathetic preganglionic fibers
Definition
Four cranial nerve pairs (including the vagus)
Term
Four cranial nerve pairs (including the vagus) carry ______ preganglionic fibers
Definition
parasympathetic
Term
Four cranial nerve pairs (including the vagus) carry parasympathetic...
Definition
preganglionic fibers
Term
the primary route of parasympathetic innervation of the internal organs
Definition
the vagus nerves
Term
some organs that the vagus nerves innervate
Definition
-Heart
-Lungs
-Esophagus
-Stomach
-Pancreas
-Liver
-Intestines
Term
The preganglionic fibers of the vagus nerves originate in the...
Definition
medulla
Term
Multiple branches of the vagus nerves synapse with postganglionic cells at...
Definition
terminal ganglia within the target tissues
Term
depiction of internal organs controlled by vagus nerves
Definition
[image]
Term
the experiment that led to the discovery of the very first neurotransmitter
Definition
[image]
-"Vagus substance" refers to the neurotransmitter causing the heartbeat
-the neurotransmitter here is acetylcholine
Term
depiction of the sympathetic and parasympathetic divisions of the autonomic nervous system and what they control
Definition
[image]
Term
ANS motor neurons are named according to...
Definition
the direction of information flow relative to peripheral ganglia
Term
the types of neurons in the ANS
Definition
-Preganglionic neuron
-Postganglionic neuron
Term
Preganglionic neuron
Definition
carries info into the ganglion
Term
Postganglionic neuron
Definition
carries info out of the ganglion
Term
ANS ganglia are named according to...
Definition
the anatomical location relative to spinal cord and/or effector organs
Term
are Paravertebral ganglia sympathetic or parasympathetic?
Definition
sympathetic
Term
are Prevertebral (collateral) ganglia sympathetic or parasympathetic?
Definition
sympathetic
Term
are Terminal ganglia sympathetic or parasympathetic
Definition
parasympathetic
Term
“SAME DAVE”
Definition
SAME = Sensory - Afferent - Motor - Efferent
DAVE = Dorsal - Afferent - Ventral - Efferent

(dorsal and ventral refers to where they come in and out of the spinal cord)
Term
the spinal roots that carry afferent (sensory) fibers
Definition
dorsal
Term
the spinal roots that carry efferent (motor) fibers
Definition
ventral
Term
Preganglionic fibers of both divisions of the ANS release this neurotransmitter
Definition
acetylcholine
(they're cholinergic)
Term
what it means for the sympathetic and parasympathetic divisions of the ANS to be antagonistic towards each other
Definition
Target organs display opposing behaviors due to release of different neurotransmitters
Term
the neurotransmitter released by most postganglionic fibers in the sympathetic division of the ANS
Definition
norepinephrine
(they're (nor)adrenergic)

however, some release acetylcholine
[image]
Term
the neurotransmitter released by most postganglionic fibers in the parasympathetic division of the ANS
Definition
acetylcholine
[image]
Term
depiction of the neurotransmitters of the autonomic nervous system in their context
Definition
[image]
red is sympathetic and blue is parasympathetic
Term
the receptor on the preganglionic fiber in the autonomic nervous system
Definition
nicotinic acetylcholine receptor (nAChR)
Term
nAChR
Definition
nicotinic acetylcholine receptor
Term
the receptor on the postganglionic fiber in the parasympathetic division of the autonomic nervous system
Definition
muscarinic acetylcholine receptor (mAChR)
Term
mAChR
Definition
muscarinic acetylcholine receptor
Term
the receptors on most postganglionic fibers in the sympathetic division of the autonomic nervous system
Definition
α1-, α2-, β1-, β2- adrenergic receptors -these are G-protein-coupled receptors
Term
one difference between epinephrine and norepinephrine
Definition
norepinephrine acts as a neurotransmitter while epinephrine acts as a hormone
Term
how the ANS postganglionic neurons (both sympathetic and parasympathetic) interact with muscles and possible other target organs
Definition
[image]
Term
why the response between preganglionic and postganglionic neurons is always excitatory
Definition
because acetylcholine is released and nicotinic acetylcholine receptors (nAChR)
Term
depiction of how the info flows from the preganglionic neurons to the postganglionic neurons to the target tissue
Definition
[image]
Term
Sympathetic Adrenergic Innervation is Excitatory in some tissues, inhibitory in others; dependent on...
Definition
receptor type and intracellular machinery
Term
Excitatory signals in the sympathetic part of the ANS cause...
Definition
(EPSP, contraction/constriction, or vesicle release) -Increase cardiac output (β1) -Vasoconstriction at some viscera (α1)
Term
Inhibitory signals in the sympathetic part of the ANS cause...
Definition
(IPSP or relaxation/dilation): -Relaxation of bronchioles (β2) -Vasodilation at some viscera (β2) -Vasodilation at skeletal muscles (β2 / muscarinic)
Term
the receptors on heart cells that contribute to increased cardiac output in response to an excitatory signal from the sympathetic part of the ANS
Definition
β1
Term
the receptors on blood vessels that contribute to vasoconstriction at some viscera in response to an excitatory signal from the sympathetic part of the ANS
Definition
α1
Term
the receptors on bronchioles that contribute to relaxation of bronchioles in response to an inhibitory signal from the sympathetic part of the ANS
Definition
β2
Term
the receptors on blood vessels that contribute to vasodilation at some viscera in response to an inhibitory signal from the sympathetic part of the ANS
Definition
β2
Term
the receptors on blood vessels that contribute to vasodilation at skeletal muscles in response to an inhibitory signal from the sympathetic part of the ANS
Definition
2 if the presynaptic cell releases norepinephrine -muscarinic if the presynaptic cell releases acetylcholine
Term
All adrenergic receptors are these types of receptors
Definition
G protein-coupled receptors (GPCRs)
Term
some downstream effects of andrenergic receptors getting activated by neurotransmitters
Definition
-Modulation of ion channel permeability
-Modulation of enzyme activity ( --> changes in ion channel permeability)
[image]
Term
what happens when β receptors get activated in the sympathetic part of the ANS?
Definition
β1-, β2-receptor activation --> increases [cAMP]i ---> smooth muscle relaxation (bronchioles; vasodilation) ---> increased heart contraction
Term
the signal transduction cascade for β-adrenergic signaling
Definition
[image]
Term
what happens when α1 receptors get activated in the sympathetic part of the ANS?
Definition
α1 -receptor activation --> increases [Ca2+]i --> smooth muscle contraction --> vasoconstriction at certain viscera
Term
what happens when α2 receptors get activated in the sympathetic part of the ANS?
Definition
receptor activation
Term
the ion that flows into the cell to activate heart contraction
Definition
Ca2+
Term
Effects of parasympathetic cholinergic innervation at target tissues can be excitatory or inhibitory depending on...
Definition
muscarinic receptor (mACh-R) subtype (all GPCRs)
Term
example of excitatory effect of parasympathetic cholinergic innervation
Definition
M3, M5 activation --> opening of Ca channels --> increased [Ca]i --> depolarization/ contraction of smooth muscles or increased gland secretions
Term
example of inhibitory effect of parasympathetic cholinergic innervation
Definition
M2 activation --> slows heart rate (via vagus) [image]
Term
how heart rate is decreased
Definition
Parasympathetic cholinergic innervation via vagus --> M2-type muscarinic receptors --> indirectly opens K+ channels --> hyperpolarization of heart muscle cells --> slowing of heart rate [image]
Term
Nicotinic vs. muscarinic receptors
Definition
[image]
Term
where nicotinic acetylcholine receptors (nAChRs) are found
Definition
postsynaptic membrane of...
-all autonomic ganglia
-all neuromuscular junctions
-some CNS pathways
Term
the effect of the signal on the postsynaptic neuron with the nicotinic acetylcholine receptors (nAChR)
Definition
excitatory
Term
the effect of the signal on the postsynaptic neuron with the muscarinic acetylcholine receptors (mAChR)
Definition
can be excitatory or inhibitory
Term
details about muscarinic acetylcholine receptors (mAChRs)
Definition
-produces parasympathetic nerve effects in the heart, smooth muscles, and glands
-G-protein-coupled receptors (receptors influence ion channels by means of G-proteins)
Term
Most visceral organs are dually-innervated, which means...
Definition
they receive input from both the sympathetic and parasympathetic sides of the ANS
Term
the relationships that can exist between the sympathetic and parasympathetic innervations of the visceral organs
Definition
-Antagonistic (most common)
-Complementary (similar effects)
-Cooperative (synergistic effects)
Term
some organs that are innervated only by the sympathetic division of the ANS
Definition
-Adrenal medulla
-Arrector pili muscles (skin)
-Sweat glands (skin)
-Most blood vessels
Term
components of the iris controlled by the ANS
Definition
-radial muscle
-circular muscle
Term
sympathetic action of the radial muscle in the iris
Definition
Contracts (dilates pupil)
Term
sympathetic receptor in the radial muscle in the iris
Definition
α1
Term
parasympathetic function of the circular muscle in the iris
Definition
Contracts (constricts pupil)
Term
parasympathetic receptor in the circular muscle in the iris
Definition
M
Term
components of the heart controlled by the ANS
Definition
-sinoatrial node
-contractility
Term
sympathetic function of the sinoatrial node in the heart
Definition
Increases heart rate
Term
sympathetic receptor in the sinoatrial node in the heart
Definition
β1
Term
parasympathetic function of the sinoatrial node in the heart
Definition
Decreases heart rate
Term
parasympathetic receptor in the sinoatrial node in the heart
Definition
M
Term
sympathetic function of the contractility in the heart
Definition
Increases
Term
sympathetic receptor in the contractility in the heart
Definition
β1
Term
parasympathetic function of the contractility in the heart
Definition
Decreases (atria)
Term
parasympathetic receptor in the contractility in the heart
Definition
M
Term
components of the vascular smooth muscle controlled by the ANS
Definition
-Skin, splanchnic vessels
-Skeletal muscle vessels
Term
sympathetic action of the Skin, splanchnic vessels in the vascular smooth muscle
Definition
Relaxes (vasodilation)
Term
sympathetic receptor in the Skin, splanchnic vessels in the vascular smooth muscle
Definition
1 -M**
Term
sympathetic function of the bronchiolar smooth muscle
Definition
Relaxes (bronchodilation)
Term
sympathetic receptor in the bronchiolar smooth muscle
Definition
β2
Term
parasympathetic function of the bronchiolar smooth muscle
Definition
Contracts (bronchoconstriction)
Term
parasympathetic receptor in the bronchiolar smooth muscle
Definition
M
Term
components of the skin controlled by the ANS
Definition
-Pilomotor smooth muscle
-Sweat glands
Term
sympathetic function of the Pilomotor smooth muscle in the skin
Definition
contracts
Term
sympathetic receptor in the Pilomotor smooth muscle in the skin
Definition
α1
Term
components of the sweat glands in the skin that are controlled by the ANS
Definition
-Thermoregulatory
-Apocrine (stress) in palms
Term
sympathetic function of the thermoregulatory in the sweat glands in the skin
Definition
Increases
Term
sympathetic receptor in the thermoregulatory in the sweat glands in the skin
Definition
M
Term
sympathetic function of the Apocrine (stress) in palms in the sweat glands in the skin
Definition
Increases
Term
sympathetic receptor in the Apocrine (stress) in palms in the sweat glands in the skin
Definition
α1s
Term
depiction of the Control of the ANS by the CNS
Definition
[image]
Term
the part of the brain that serves as command central for both the ANS and the endocrine system
Definition
hypothalamus
Term
Sensory Physiology is about...
Definition
How we perceive our environment
Term
Three common steps associated with any sense
Definition
-A physical stimulus
-Sensory transduction: transformation of sensory input into nerve impulses
-Formulation of “perception”, or our conscious experience of that sensation
Term
Sensory transduction
Definition
transformation of sensory input into nerve impulses
Term
the 6 sensory systems
Definition
-somatosensory
-Visual
-Auditory
-Vestibular
-Olfactory
-Gustatory
Term
some senses within the somatosensory system
Definition
-Touch
-Proprioception
-Temperature
-Pain
Term
vestibular system
Definition
sense of balance
Term
gustatory system
Definition
sense of taste
Term
Four basic types of information conveyed by each sensory system
Definition
-Modality (type) of stimulus
-Intensity of stimulus
-Time course of stimulus
-Location of stimulus
Term
what the sensory cells are
Definition
-Some are themselves neurons (afferent)
-Most are specialized epithelial cells that synapse on adjacent sensory neurons
Term
the 4 functional classes of sensory receptors
Definition
-Mechanoreceptors
-Chemoreceptors
-Thermoreceptors
-Photoreceptors
Term
what sensory receptors at the protein level
Definition
-Channels (e.g. stretch receptors)
-GPCR’s (e.g. photoreceptors of retina)
Term
mechanoreceptors
Definition
-sense pressure and movement
-found in skin, muscles, and ears
Term
photoreceptors
Definition
-sense light
-found in eyes
Term
chemoreceptors
Definition
-sense chemicals
-found in the nose and mouth
Term
thermoreceptors
Definition
-sense temperature
-found in the skin
Term
nociceptors
Definition
-sense pain
-found in skin
Term
receptors that are channels at the protein level
Definition
-stretch receptors
-ear proteins that detect sound
[image]
Term
receptors that are GPCRs at the protein level
Definition
photoreceptors of retina
[image]
Term
some other somatic senses
Definition
-Pain
-Temperature
-Itch
-Proprioception
Term
Each sensory receptor responds to...
Definition
a particular modality
Term
The sensory receptor transduces the external stimulus into...
Definition
changes in membrane potential
Term
2 ways the sensory receptor transduces the external stimulus into changes in membrane potential
Definition
-Stimulus transduction
-Receptor/generator potential
Term
Stimulus intensity is encoded by...
Definition
action potential frequency in sensory neuron
Term
Generator potentials
Definition
Produced in specialized dendritic processes of primary sensory neuron (= sensory receptor)
Term
Receptor potentials
Definition
-Produced in specialized epithelial cell (= sensory receptor)
-Communicated to associated primary sensory neuron
Term
depiction of Receptor vs. Generator Potentials
Definition
[image]
Term
Duration of sensation is in part encoded by...
Definition
adaptation of receptors
Term
types of receptors that adapt
Definition
-Phasic receptors
-Tonic receptors
Term
Phasic receptors
Definition
fast-adapting
[image]
Term
Tonic receptors
Definition
slow-adapting
[image]
Term
what encodes the location of a stimulus?
Definition
the receptive field of a sensory neuron
Term
the receptive field
Definition
encodes the location of the stimulus
[image]
each circled area is a separate receptive field
Term
In sensory systems, the receptive field is oftentimes comprised of a ______ and a ______
Definition
“center”
“surround”
[image]
Term
how the "center" and the "surround" of the receptive field in a sensory system and the associated cortical neurons react to touch
Definition
[image]
Term
soma modalities detected by somatosensory perception
Definition
-Touch
-Proprioception
-Temperature
-Pain
-Itch
Term
some types of somatosensory receptors
Definition
-cutaneous (skin) receptors
-proprioceptors
Term
some types of cutaneous (skin) receptors
Definition
-Touch/pressure R’s
-Hot/cold R’s
-Nociceptors (pain R’s)
Term
some types of propioceptors
Definition
-Muscle spindles
-Golgi tendon organs
-Joint R’s
Term
how cutaneous receptors transmit information
Definition
by converting change in pressure into signals
Term
depiction of the types of cutaneous receptors in the skin
Definition
[image]
Term
attenuating a stimulus
Definition
receptors ignoring a benign stimulus that doesn't go away
Term
the 4 types of touch receptors, their receptive fields, and their intensity and time course
Definition
[image]
Term
the ascending pathway used by the 4 types of touch receptors
Definition
medial lemniscal tract
Term
the components of the eye you're expected to be familiar with
Definition
-Cornea
-Iris
-Pupil
-Lens
-Retina
-Fovea
-Optic Nerve
-Vitreous Humor
Term
anatomy of the eye
Definition
[image]
Term
the white of the eyes comes from the...
Definition
sclera
[image]
Term
the sclera is continuous with the...
Definition
cornea
[image]
Term
the phototransduction of the eyeball
Definition
the retina
[image]
Term
iris made of...
Definition
muscles
[image]
Term
fovea
Definition
very small little divot, only about 2 millimeters in diameter, that constitutes the very center of your field of vision
[image]
Term
which part of the eye is responsible for ability to create a very sharp image in the very center of our visual field, a color image?
Definition
the fovea centralis, which strictly contains cones corresponding to 3 different wavelengths
[image]
Term
the part of the retina that has a heavier concentration of rod cells
Definition
peripheral retina (outside the fovea)
[image]
Term
what's in charge of the peripheral vision? rods or cones?
Definition
rods
Term
optic disc
Definition
where the optic nerve exits the retina
-this is also where the blind spot is, because of no photoreceptors
[image]
Term
where the eye's blind spot is
Definition
the optic disc, since there's no photoreceptors there
Term
vitreous humor
Definition
basically the fluid-filled cavity in the eyeball
[image]
Term
why we have depth perception
Definition
because of the overlapping visual fields of each eye
Term
depiction of how the light rays go through the eye
Definition
[image]
notice that each eye has a left and right visual field
Term
optic chiasma
Definition
the area of crossover between the optic nerves
[image]
Term
how the crossover works in terms of the visual field
Definition
for each eye, one field remains ipsilateral and the other is contralateral such that the left visual field gets to the right side of the brain and the right visual field gets to the left side of the brain
[image]
Term
the muscles responsible for dilation of the pupil
Definition
radial muscles, which are sympathetic
Term
the muscles responsible for contraction of the pupil
Definition
circular muscles, which are parasympathetic
Term
depiction of the autonomic control of pupil diameter
Definition
[image]
for both, the effect is stimulatory
Term
______ of the retina transduce electromagnetic energy, in the form of photons
Definition
Photoreceptor cells (PRCs)
Term
Photoreceptor cells (PRCs) of the retina ______ electromagnetic energy, in the form of photons
Definition
transduce
Term
the 2 types of Photoreceptor cells (PRCs)
Definition
-rods
-cones
Term
details about the rods of the retina
Definition
-Dim-light vision
-Greater sensitivity to light
-Rhodopsin is the light-receptor
Term
details about the cones of the retina
Definition
-Color vision
-Greater visual acuity
-Photopsins are the light-receptors
Term
the vertical pathway within the retina
Definition
PRCs --> Bipolar cells --> Ganglion cells (optic nerve)
Term
the 3 different types of cones
Definition
-S
-M
-L
Term
the light receptors in the rod cells of the retina
Definition
rhodopsins, which are GPCRs
Term
the light receptors in the cone cells of the retina
Definition
photopsins, which are GPCRs
Term
the cells that ultimately fire off action potentials corresponding to vision
Definition
Ganglion cells (optic nerve)
Term
depiction of everything the light rays have to go through before phototransduction can occur
Definition
[image]
Term
anatomy of the retina
Definition
[image]
Term
retinal
Definition
the photopigment that gets activated by the incoming light rays
Term
role of the pigmented epithelium
Definition
-Homeostasis of PRCs
-Visual cycle of retinal; they recycle retinal
Term
location of the PRCs
Definition
the back of the retina
[image]
Term
the neurons that mediate lateral information flow in visual processing
Definition
interneurons
Term
some interneurons mediate lateral information flow
Definition
-Horizontal cells
-Amacrine cells
Term
depiction of the rod and cone cells
Definition
[image]
Term
what the synaptic endings of rod and cone cells do to transmit a signal
Definition
release neurotransmitters that communicate with bipolar cells
Term
the parts of the rod and cone cells that have all the phototransduction equipment
Definition
the rod and cone-shaped structures that contain layers of membranes
Term
some things rod and cone cells have in common
Definition
-their Photoreceptors are GPCR’s
-Photopigment is retinal
-G-protein is transducin
-"dark current," in which...
+PRCs are depolarized in dark
+PRCs are hyperpolarized in light
Term
the GPCR in rods
Definition
rhodopsin
Term
the GPCR in cones
Definition
photopsin
Term
what the inside of the rod and cone cells looks like
Definition
[image]
notice that the only real architectural difference is that the stack of membranes in the cone is infoldings of the membrane while the stack of membranes in the rod is intracellular
Term
structure of the membrane in the rod
Definition
[image]
the receptor here is a GPCR
Term
how rod cells behave in dark and light
Definition
[image]
Term
how phototransduction in a rod occurs
Definition
-λ (photon) activates Rhodopsin -Rhodopsin activates Gt (transducin), causing the alpha and beta-gamma subunits to dissociate -Gα(GTP) activates cGMP-dependent phosphodiesterase (PDE) -PDE decreases [cGMP]i -Decreased [cGMP]i closes Na+ channels -Decreased Na+ influx hyperpolarizes the rod cell -Hyperpolarization means decreased neurotransmitter release at PRC/BPC synapse
Term
how the photopigment gets activated
Definition
[image]
Term
how the photopigment gets recycled
Definition
[image]
Term
depiction of how phototransduction occurs in a rod
Definition
[image]
Term
depiction of the vertical pathway in vision
Definition
[image]
Term
the effect of glutamate in the vertical pathway in vision
Definition
inhibitory
[image]
Term
the receptors on the ganglion cells that consist of the optic nerve
Definition
iGluRs
Term
PRC
Definition
photoreceptor cells
Term
BPC
Definition
bipolar cell
Term
GC
Definition
ganglionic cell
Term
the wavelength absorbed by rods
Definition
blue/green
Term
the types of cones in the retina
Definition
-S cones
-M cones
-L cones
Term
S cones
Definition
-short wavelength
-blue
Term
M cones
Definition
-medium wavelength
-green
Term
L cones
Definition
-long wavelength
-red
Term
depiction of the distribution of the rods and cones in the fovea
Definition
[image]
notice the indentation where the light has an easier time getting to the photoreceptors
Term
distribution of cones in different parts of the retina
Definition
[image]
Term
how convergence of information occurs in the retina
Definition
[image]
Term
one reason we have better visual acuity in the fovea than in the peripheral part of the retina
Definition
because the cones in the fovea each bind with one bipolar cell, which binds to one ganglion cell; this means no convergence
[image]
notice that several rods bind to one bipolar cell, and more than one bipolar cell binds to the ganglion cell,; this means convergence
Term
depiction of the receptive field on the retina
Definition
[image]
Term
the information flow in vision
Definition
PRCs --> BPCs --> ganglion cells --> thalamic neurons (LGN) --> cortical neurons in the occipital lobe of the brain
Term
“On-center” ganglionic cells
Definition
they are most stimulated by central illumination & darkness in the surround
Term
“Off-center” ganglionic cells
Definition
they are most stimulated by surround illumination & darkness in the center
Term
depiction of how on- and off-center ganglionic cells detect contrast
Definition
[image]
Term
endocrinology
Definition
The study of endocrine glands/tissue, the hormones they release, and their effects on target tissues
Term
Hormones are carried via...
Definition
the blood
Term
Hormones regulate...
Definition
-body metabolism
-growth
-reproduction
Term
major hormones released by the hypothalamus
Definition
Releasing and inhibiting hormones
Term
primary target organ of the Releasing and inhibiting hormones released by the hypothalamus
Definition
anterior pituitary
Term
primary effects of the Releasing and inhibiting hormones released by the hypothalamus
Definition
Regulates secretion of anterior pituitary hormones
Term
major hormones released by the pituitary gland, anterior lobe
Definition
Trophic hormones
Term
major target organs of the Trophic hormones released by the pituitary gland, anterior lobe
Definition
Endocrine glands and other organs
Term
primary effects of the Trophic hormones released by the pituitary gland, anterior lobe
Definition
Stimulates growth and development of target organs; stimulates secretion of other hormones
Term
major hormones released by the pituitary gland, posterior lobe
Definition
Antidiuretic hormone Oxytocin
Term
primary target organs of the Antidiuretic hormone Oxytocin released by the pituitary gland, posterior lobe
Definition
Kidneys and blood vessels Uterus and mammary glands
Term
primary effects of the Antidiuretic hormone Oxytocin released by the pituitary gland, posterior lobe
Definition
Antidiuretic hormone promotes water retention and vasoconstriction; oxytocin stimulates contraction of uterus and mammary secretory units, promoting milk ejection
Term
major hormones released by the thyroid gland
Definition
Thyroxine (T4) and triiodothyronine (T3); calcitonin
Term
primary target organs of the Thyroxine (T4) and triiodothyronine (T3) and calcitonin
Definition
most organs
Term
primary effects of the Thyroxine (T4) and triiodothyronine (T3) and calcitonin
Definition
Thyroxine and triiodothyronine promote growth and development and stimulate basal rate of cell respiration (basal metabolic rate or BMR); calcitonin may participate in the regulation of blood Ca2+ levels
Term
components of the adrenal glands
Definition
-adrenal cortex
-adrenal medulla
Term
major hormones released by the adrenal cortex
Definition
Glucocorticoids (mainly cortisol) Mineralocorticoids (mainly aldosterone)
Term
primary target organs of the Glucocorticoids (mainly cortisol) and Mineralocorticoids (mainly aldosterone) released by the adrenal cortex
Definition
-Liver
-muscles
-Kidneys
Term
primary effects of the Glucocorticoids (mainly cortisol) and Mineralocorticoids (mainly aldosterone) released by the adrenal cortex
Definition
Glucocorticoids influence glucose metabolism; mineralocorticoids promote Na+ retention, K+ excretion
Term
major hormones released by the adrenal medulla
Definition
Epinephrine
Term
major target organs of the Epinephrine released by the adrenal medulla
Definition
-Heart
-bronchioles
-blood vessels
Term
primary effects of the Epinephrine released by the adrenal medulla
Definition
Causes adrenergic stimulation
Term
major hormones released by the pancreas
Definition
-Insulin
-Glucagon
Term
primary target organs of the insulin and glucagon released by the pancreas
Definition
-Liver
-skeletal muscle
-adipose tissue
Term
primary effects of the insulin and glucagon released by the pancreas
Definition
Insulin promotes cellular uptake of glucose and formation of glycogen and fat; glucagon stimulates hydrolysis of glycogen and fat
Term
hormones formed from...
Definition
Inactive hormone precursor molecules (prohormones & prehormones (a.k.a. preprohormones))
Term
prohormones & prehormones (a.k.a. preprohormones)
Definition
Inactive hormone precursor molecules

prehormone/preprohormones --> prohormones --> hormones
Term
The nervous & endocrine systems overlap in terms of...
Definition
chemical transmitters and receptor proteins
Term
most target tissues are regulated by how many hormones?
Definition
multiple (more than 1)
Term
the downstream effects hormones have on target tissues
Definition
-mostly antagonistic
-can be complementary
Term
the response of the target tissue can change as a function of...
Definition
the circulating concentrations of hormones in the blood supply
Term
when you tend to see sensitization or upregulation of the response of the target tissue
Definition
when the hormone is changing within the physiological range
Term
when you tend to see desensitization or down regulation of the target tissue
Definition
when you have pharmacological ranges, or toxic ranges, of circulating hormones, or perhaps the presence of synthetic hormones or hormone mimetics
Term
2 ways to classify hormones
Definition
-chemical structures
-physical properties
Term
groups of hormones based on chemical structure
Definition
-amino acid derivatives
-peptides and proteins
-steroids
Term
groups of hormones based on physical properties
Definition
-hydrophilic
-hydrophobic
Term
some hormones that are amino acids or derivatives of amino acids
Definition
-Epinephrine & norepinephrine (adrenal medulla)
-Thyroid hormones
-Melatonin (pineal gland)
Term
some hormones that are peptides and proteins
Definition
-Hypothalamic & pituitary hormones
-Insulin & glucagon (pancreas)
-Parathyroid hormone
Term
some hormones that are steroids
Definition
-Corticosteroids (adrenal cortex)
-Sex steroids (gonads)
Term
most of our hormones fit into this chemical structure group of hormones
Definition
peptides and proteins
Term
steroids are derived from...
Definition
cholesterol
Term
what makes the big difference in terms of what type of receptor the hormone will interact with at target tissues?
Definition
whether the hormone is hydrophilic or hydrophobic
Term
2 groups of hormones based on physical properties
Definition
-hydrophilic
-hydrophobic
Term
Hydrophilic hormones interact with...
Definition
cell-surface receptors at target tissues
Term
Hydrophobic (or lipophilic) hormones interact with...
Definition
intracellular receptors at target tissues
Term
some hormones that are hydrophilic
Definition
-All peptide & protein hormones
-Epinephrine & norepinephrine
Term
some hormones that are hydrophobic
Definition
-Steroid hormones
-Thyroid hormones
Term
the vast majority of hormones are hydrophilic or hydrophobic?
Definition
hydrophilic
Term
the different types of cellular receptors hormones interact with
Definition
-enzyme-linked
-GPCRs
-intracellular
Term
how enzyme-linked receptors react to hormones
Definition
they act through intracellular 2nd messengers (cAMP, Ca2+, kinases)
Term
some hormones that interact with enzyme-linked receptors
Definition
-insulin
-growth factors
Term
how GPCRs react to hormones
Definition
they act through intracellular 2nd messengers (cAMP, Ca2+, kinases)
Term
some hormones that interact with GPCRs
Definition
-Epinephrine
-norepinephrine
Term
how intracellular receptors react to hormones
Definition
they act as transcription factors in the nucleus
Term
some hormones that interact with intracellular receptors
Definition
-Steroids
-thyroid hormones
Term
the types of receptors hormones interact with and what those receptors look like
Definition
[image]
Term
the pancreas is not under the control of the...
Definition
hypothalamic-pituitary axis (HPA)
Term
hormones released by the pancreas
Definition
-insulin
-glucagon
Term
the endocrine portion of the pancreas
Definition
The islets of Langerhans
Term
The islets of Langerhans
Definition
the endocrine portion of the pancreas
Term
2 types of endocrine cells in the pancreas
Definition
-alpha-cells
-beta-cells
Term
alpha-cells in the pancreas
Definition
secrete glucagon
Term
beta-cells in the pancreas
Definition
secrete insulin
Term
Changes in ______ influence secretion of pancreatic hormones
Definition
blood glucose levels
Term
Pancreatic hormones regulate...
Definition
blood-glucose levels
Term
Pancreatic hormones influence...
Definition
cellular metabolism
Term
how insulin influences cell metabolism
Definition
Insulin --> anabolism
Term
how glucagon influences cell metabolism
Definition
Glucagon --> catabolism
Term
target tissues of the insulin and glucagon released by the pancreas
Definition
-liver
-skeletal muscle
-adipocytes
Term
depiction of alpha and beta cells in the pancreas
Definition
[image]
Term
comparison of Anabolism vs. Catabolism
Definition
[image]
Term
anabolic processes
Definition
promote the creation of larger molecules

consumes energy
Term
catabolism
Definition
breakdown of larger molecules into smaller byproducts

releases energy
Term
the effect of glucagon on the liver
Definition
breakdown of glycogen such that free glucose is released into the bloodstream
Term
depiction of how the pancreas responds to changes in glucose levels
Definition
[image]
Term
2 processes that are activated by glucagon
Definition
-glycogenolysis
-gluconeogenesis
Term
the structure of insulin from preprohormone to active hormone
Definition
[image]
Term
the most prevalent type of enzyme-linked cell surface receptor
Definition
Receptor tyrosine kinases (RTKs)
[image]
Term
The insulin receptor is this kind of receptor
Definition
a Receptor tyrosine kinases (RTKs)
[image]
Term
Kinases
Definition
enzymes that phosphorylate proteins
Term
Tyrosine kinases
Definition
they attach phosphate groups to tyrosine residues within proteins
Term
what phosphorylates the activated insulin receptor?
Definition
the activated insulin receptor phosphorylates itself
Term
depiction of how the insulin receptor gets activated
Definition
[image]
Term
what activates the kinase activity of the intracellular side of the insulin receptor?
Definition
binding of insulin
Term
depiction of how insulin stimulates the uptake of blood glucose
Definition
[image]
Term
effect of insulin on liver and muscle
Definition
Increases glycogen synthesis (glucose --> glycogen)
Term
effect of insulin on adipocytes (fat)
Definition
Increases fat stores (glucose --> triglycerides)
Term
GLUT4
Definition
insulin-dependent glucose uniporter found only in skeletal muscle, cardiac muscle, and fat cells
[image]
Term
metabolic effect of insulin
Definition
as glucose enters the cell, enzymes that make glycogen are activated

Increases glycogen synthesis (glucose --> glycogen) in liver & muscle
Increases fat stores in adipocytes (glucose --> triglycerides)
Term
GLUT2
Definition
insulin-independent glucose transporter found on hepatocytes that moves glucose into the cells when blood glucose is high and out of the cells when blood glucose is low
Term
When blood glucose increases, >95% of blood glucose is taken up by...
Definition
muscle & fat tissues (~90/10 muscle/fat)
Term
Major effect of insulin at the liver
Definition
to decrease gluconeogenesis & increase glycogen synthesis
Term
Major effect of glucagon is at the liver
Definition
to increase glycogenolysis & gluconeogenesis
Term
Exercise increases ______ levels and decreases ______ levels, probably due to...
Definition
glucagon
insulin
lowered blood glucose levels
Term
of the glucose that gets taken up by muscle and fat tissue, how much goes to muscle and how much goes to fat?
Definition
~90% muscle
~10% fat
Term
hormones released by the hypothalamus that communicate with the pituitary gland
Definition
-Releasing hormones
-Inhibiting hormones
Term
hormones released from the anterior pituitary
Definition
-GH
-TSH
-ACTH
-FSH
-LH
-prolactin
Term
hormones released from the posterior pituitary
Definition
-ADH
-Oxytocin
Term
the "master controller" of most of our endocrine systems
Definition
the Hypothalamus/Pituitary Axis (HPA)
Term
the Hypothalamus/Pituitary Axis (HPA) is responsible for the integration of the...
Definition
neuro and endocrine systems
Term
pituitary gland aka...
Definition
hypophysis
Term
Anterior lobe of pituitary gland aka...
Definition
adenohypophysis
Term
Posterior lobe of pituitary gland aka...
Definition
neurohypophysis
Term
how the hypothalamus regulates the anterior lobe of the pituitary gland (adenohypophysis)
Definition
by way of hormones
Term
how the hypothalamus regulates the posterior lobe of the pituitary gland (neurohypophysis)
Definition
neurologically
-this is actually a neural extension of the hypothalamus
Term
depiction of the pituitary gland and the hypothalamus
Definition
[image]
Term
depiction of the anatomical and functional details of hypothalamic control of the posterior and anterior pituitary glands
Definition
[image]
Term
how the hypothalamus makes the posterior pituitary release ADH and oxytocin into the bloodstream
Definition
-neurologically
-each nucleus from the hypothalamus is used for one hormone or the other, not both
-the nerve terminals send the hormone into the blood stream
[image]
Term
how the hypothalamus makes the anterior pituitary release anterior pituitary hormones into the bloodstream
Definition
-neurologically within the hypothalamus
-portal venules carry hormones into the anterior pituitary
-these hormones regulate release of pituitary hormones into the secondary capillaries
Term
how the signal gets from the hypothalamus to the posterior pituitary
Definition
Supraoptic & paraventricular nuclei of the hypothalamus produce two hormones which are transported down the hypothalamo-hypophyseal tract to the posterior pituitary
Term
how hormones from the posterior pituitary are released into the blood
Definition
When hypothalamic neurons are stimulated, their nerve endings in the posterior pituitary release these hormones into the general circulation
Term
effects of oxytocin
Definition
-Uterine contractions during labor
-Contraction of mammary glands during lactation
Term
ADH aka...
Definition
vasopressin
Term
effects of ADH aka vasopressin
Definition
Water reabsorption by the kidneys
Term
depiction of how ADH is involved in thirst and drinking
Definition
[image]
Term
2 hormones you need to know that are released from the hypothalamus to control the anterior pituitary
Definition
-corticotropin-releasing hormone (CRH)
-thyrotropin-releasing hormone (TRH)
Term
structure of corticotropin-releasing hormone (CRH)
Definition
41 amino acids
Term
effect of corticotropin-releasing hormone (CRH) on the anterior pituitary
Definition
stimulates secretion of adrenocorticotropic hormone (ACTH)
Term
structure of thyrotropin-releasing hormone (TRH)
Definition
3 amino acids
Term
effect of thyrotropin-releasing hormone (TRH) on the anterior pituitary
Definition
stimulates secretion of thyroid-stimulating hormone (TSH)
Term
details for how the hypothalamus controls the anterior pituitary
Definition
-Various releasing and inhibiting hormones are produced in the hypothalamus
-Hypothalamic nerve endings secrete these hormones into a capillary/venule system known as the hypothalamo-hypophyseal portal system
-These hormones regulate the secretion of anterior pituitary hormones; these pituitary hormones then travel through the bloodstream to effector organs, including other endocrine glands
Term
the hypothalamo-hypophyseal portal system
Definition
the capillary-venule system that hypothalamic nerve endings secrete hormones into
Term
effect of ACTH
Definition
causes the adrenal cortex to release certain steroid hormones, such as glucocorticoids
Term
one type of steroid hormone released by the adrenal cortex in response to ACTH
Definition
glucocorticoids
Term
effect of TSH
Definition
causes thyroid to release thyroid hormones, such as T3 and T4 or throxine
Term
Trophic hormones
Definition
suffix “-tropin”
-they have an endocrine role where they're going to cause some sort of endocrine function to happen, perhaps the release of another hormone that will go do its job
-these hormones also have a nutritive function, that is, growth effect for those target tissues
Term
Negative feedback-inhibition
Definition
a common theme in target gland-mediated regulation of the anterior pituitary and/or hypothalamus
Term
Higher brain centers can influence activity of ______, thus influencing...
Definition
hypothalamic nuclei
downstream endocrine systems
Term
Thyroid-stimulating hormone (TSH)
Definition
promotes production & secretion of T3 & T4 in the thyroid
Term
Adrenocorticotropic hormone (ACTH)
Definition
promotes secretion of glucocorticoids in the adrenal cortex
Term
the 2 components of the adrenal glands
Definition
-adrenal medulla
-adrenal cortex
Term
hormones released by the adrenal medulla
Definition
-Epinephrine
-Norepinephrine
Term
hormones released by the adrenal cortex
Definition
-Glucocorticoids
-Mineralocorticoids
-Sex steroids
Term
Adrenal medulla
Definition
-Secretes epinephrine & norepinephrine into the blood
-Stimulated by the sympathetic nervous system
Term
Adrenal cortex
Definition
-Secretes corticosteroids, or steroid hormones, into the blood
-Arranged into three layers, or zones
+Zona glomerulosa --> mineralocorticoids
+Zona fasciculata & zona reticularis --> glucocorticoids & sex steroids
Term
the three layers, or zones, of the adrenal cortex
Definition
-Zona glomerulosa --> mineralocorticoids
-Zona fasciculata & zona reticularis --> glucocorticoids & sex steroids
[image]
Term
the adrenal medulla is not controles by...
Definition
the HPA
Term
adrenal medulla controlled by...
Definition
sympathetic nervous system
Term
epinephrine & norepinephrine are in this group of hormones
Definition
catecholamines
Term
Catecholamine hormones released by the adrenal medulla
Definition
-epinephrine
-norepinephrine
Term
some sympathoadrenal effects of the catecholamine hormones (epinephrine and norepinephrine) released by the adrenal medulla
Definition
-Increase cardiac output
-Increase heart rate
-Dilate blood vessels to heart
-Increase alertness
-Increase respiratory rate
-Increase metabolic rate
Term
some metabolic effects of the catecholamine hormones (epinephrine and norepinephrine) released by the adrenal medulla
Definition
-Increase glycogenolysis in the liver
-Increase lipolysis in the adipose tissue
Term
what epinephrine released from the adrenal medulla does
Definition
it mediates its effects at target tissues via activation of GPCRs that increase intracellular second messengers, such as cAMP and calcium
Term
some intracellular second messengers
Definition
-cAMP
-calcium
Term
the receptors that lead to increased intracellular cAMP
Definition
beta receptors
Term
the receptors that lead to increased intracellular cytosolic calcium
Definition
alpha receptors
Term
depiction of how epinephrine binding to beta-adrenergic receptors leads to increased intracellular cAMP
Definition
[image]
beta-receptor --> G-protein --> adenylyl cyclase --> cAMPi --> protein kinase A --> other kinases --> downstream effects
-in this case, the alpha subunit interacts with the downstream effector
Term
depiction of how alpha-adrenergic receptors lead to increased cytosolic calcium concentration
Definition
[image] alpha-receptor --> G-protein --> PLC --> IP3 --> Ca2+i --> Ca/calmodulin --> kinases --> downstream effects -IP3 receptors are Ca channels on the endoplasmic reticulum
Term
DAG
Definition
diacylglycerol
Term
IP3 receptors
Definition
Ca channels on the endoplasmic reticulum
Term
where in the cell Ca is usually stored
Definition
ER (sarcoplasmic reticulum in muscle cells)
Term
why release of Ca into the cytosol leads to downstream events
Definition
because of Ca binding to calmodulin
Term
depiction of the metabolic effects of epinephrine in a liver cell
Definition
[image]
Term
the adrenal cortex is controlled by the...
Definition
the hypothalamic pituitary axis (HPA)
Term
mineralocorticoids
Definition
steroids that regulate electrolytes, such as Na+ and K+
Term
glucocorticoids
Definition
steroids that regulate glucose and other metabolites (catabolic effects)
-also play a role in immune suppression & inhibition of inflammation
Term
Zona glomerulosa
Definition
-layer of the adrenal cortex
-releases mineralocorticoids
[image]
Term
Zona fasciculata & zona reticularis
Definition
-layers of the adrenal cortex
-release glucocorticoids & sex steroids
[image]
Term
depiction of how corticosteroids are made from cholesterol in the adrenal cortex
Definition
[image]
Term
Sex steroids
Definition
weak androgens that supplement gonadal hormones
Term
an example of a mineralocorticoid
Definition
aldosterone, probably the most important mineralocorticoid
Term
Aldosterone
Definition
a mineralocorticoid that increases Na+ and H2O retention as well as K+ excretion in the kidneys --> increases blood volume & pressure; balances electrolytes
Term
an example of a glucocorticoid
Definition
cortisol
Term
Cortisol
Definition
increases blood glucose levels by stimulating gluconeogenesis & inhibiting glucose utilization in the tissues; it also increases free fatty acid levels in the blood by stimulating lipolysis
Term
how cortisol increases blood glucose levels
Definition
by stimulating gluconeogenesis & inhibiting glucose utilization in the tissues
Term
how cortisol increases free fatty acid levels in the blood
Definition
by stimulating lipolysis
Term
steroids hydrophilic or hydrophobic?
Definition
hydrophobic
Term
how steroids travel through the blood stream
Definition
by binding to “carrier proteins”
Term
carrier proteins
Definition
proteins steroids bind to so they can travel through the blood stream
Term
the effect of steroids on target organs
Definition
-they bind to & activate intracellular nuclear hormone receptors, which then function as transcription factors (canonical “genomic” mechanism of action)
-they may also mediate non-genomic responses in target tissues
Term
the specific receptors steroids bind to
Definition
intracellular nuclear hormone receptors, which then function as transcription factors
Term
depiction of how steroids get through the blood to their target tissues
Definition
[image]
Term
the part of the receptor protein that binds to the steroid hormone
Definition
the ligand-binding domain
Term
for the hormone-bound receptor to act as a transcription factor, the monomers have to...
Definition
come together to form a homodimer
[image]
Term
homodimer
Definition
the pair of receptor proteins that join to act as a transcription factor
[image]
Term
depiction of the Hypothalamic-pituitary-adrenal axis: negative feedback control
Definition
[image]
Term
the hormones released by the thyroid gland
Definition
-Thyroid hormone (T3, T4) -Calcitonin
Term
Thyroid hormone (T3, T4) released by which cells in the thyroid gland?
Definition
the follicular cells
Term
role of Thyroid hormone (T3, T4)
Definition
-Regulation of body metabolism
-Regulation of growth & development, particularly the brain
Term
depiction of the follicles in the thyroid
Definition
[image]
Term
secretion of Thyroid hormone (T3, T4) stimulated by...
Definition
TSH released from the anterior pituitary
Term
role of calcitonin
Definition
Regulation of blood calcium levels
Term
calcitonin secreted by which cells in the thyroid?
Definition
the parafollicular cells
Term
TRH
Definition
thyrotropin-releasing hormone
Term
TSH
Definition
thyroid-stimulating hormone
Term
how the thyroid hormones (T3, T4) are produced
Definition
-Hypothalamus secretes TRH (thyrotropin-releasing hormone) --> anterior pituitary secretes TSH (thyroid-stimulating hormone) --> thyroid gland secretes T3 & T4
-Thyroid follicular cells transport iodide from the blood into the colloid
-Iodine is attached to tyrosine residues on thyroglobulin (MIT & DIT)
[image]
Term
difference between thyroid hormones T3, T4
Definition
[image]
Term
is there more T3 or T4?
Definition
T4; about 20 times more of it
Term
depiction of how thyroid hormones are produced in and released from the follicles
Definition
[image]
you don't need to know the names of any of these enzymes
Term
thyroid hormone T4 aka...
Definition
thyroxine
Term
TBG
Definition
thyroxine-binding globulin -this is the carrier-protein for T4 in blood
Term
thyroid hormones hydrophilic or hydrophobic?
Definition
hydrophobic
Term
specific details on how thyroid hormone is produced and released
Definition
[image] 1: follicular cell synthesizes enzymes and thyroglobulin for colloid 2: a Na+-I- symporter brings I- into the cell. The pendrin transporter moves I-into the colloid. 3: enzymes add iodine to tyrosine to make T3 and T4 4: thyroglobulin is taken back into the cell in vesicles 5: intracellular enzymes separate T3 and T4 from the protein 6: free T3 and T4 enter circulation
Term
thyroid hormones T3 and T4 are derivatives of...
Definition
tyrosine
Term
thyroid hormones T3 and T4 diffuse through...
Definition
membranes
Term
target tissues of thyroid hormones T3 and T4
Definition
-liver
-skeletal and cardiac muscles
-bones
-brain
Term
effect of thyroid hormones T3 and T4 on the liver
Definition
promotes glucose metabolism & gluconeogenesis
Term
effect of thyroid hormones T3 and T4 on the skeletal and cardiac muscles, bones, and brain
Definition
promotes normal growth & development
Term
the active form of thyroid hormone within the cells
Definition
T3
Term
the mechanism of action for thyroid hormone
Definition
[image]
Term
the Hypothalamo-pituitary-thyroid axis
Definition
[image]
Term
trophic effect
Definition
when hormones have a nourishing effect on their target tissues
Term
2 types of effects TSH has on the thyroid
Definition
-trophic
-hormonal
Term
some conditions that can result from thyroid dysfunction
Definition
-hypothyroid
-hyperthyroid
-goiter
Term
Hypothyroid
Definition
decreased levels of T4 in blood
Term
Hyperthyroid
Definition
increased levels of T4 in blood
Term
Goiter
Definition
abnormal growth of the thyroid gland
Term
types of goiter that can occur
Definition
-iodine insufficiency (endemic goiter)
-Grave's disease (toxic goiter)
Term
endemic goiter caused by...
Definition
iodine insufficiency
Term
some details about iodine insufficiency (endemic goiter)
Definition
Hypothyroid condition
Low levels of circulating T4 --> no negative feedback on anterior pituitary --> elevated TSH --> trophic effects on thyroid gland --> goiter
Term
some details about Grave's disease (toxic goiter)
Definition
Hyperthyroid condition
Autoantibodies mimic TSH effects at thyroid --> excessive T4 in blood, but autoantibodies circumvent normal negative feedback loop --> goiter
Term
the pathway by which lack of iodine leads to goiters
Definition
[image]
Term
depiction of how Graves's disease leads to goiter
Definition
[image] -notice that the antibody activates the receptor; it's an agonist -this is a constant trophic effect that leads to producing too much T4
Term
the types of muscle in the human body
Definition
-skeletal
-smooth
-cardiac
[image]
Term
the muscles tat do not have striations
Definition
smooth muscles
Term
what causes striations in skeletal and cardiac muscle?
Definition
overlap of filaments
Term
what all muscle types have in common
Definition
-Contraction occurs by sliding of actin & myosin filaments
-Excitation/contraction coupling relies on increases in intracellular calcium
Term
Contraction occurs in all muscle types by...
Definition
sliding of actin & myosin filaments
Term
Excitation/contraction coupling in all muscle types relies on...
Definition
increases in intracellular calcium
Term
some general details about skeletal muscles
Definition
-Sarcomere is the smallest contractile unit, giving it a striated (striped) appearance
-Control by somatic motor neurons
Term
some general details about cardiac muscles
Definition
-Sarcomere is the smallest contractile unit, giving it a striated (striped) appearance
-Pacemaker cells: automatic rhythmic action potentials & contractions
-Regulation of strength & frequency of contraction by autonomic motor neurons
Term
some general details about smooth muscles
Definition
-No sarcomeres; no striated appearance
-Control by autonomic motor neurons
Term
SARCOMERE
Definition
smallest contractile unit of muscle cell
Term
MYOFIBRIL
Definition
serially-repeating sarcomeres (a single muscle cell contains many myofibrils)
[image]
Term
MUSCLE FIBER or MYOFIBER
Definition
muscle cell
[image]
Term
FASCICULUS
Definition
bundle of muscle fibers
[image]
Term
MUSCLE
Definition
bundle of fasciculi
[image]
Term
SARCOLEMMA
Definition
plasma membrane of a muscle cell
Term
SARCOPLASM
Definition
cytoplasm of a muscle cell
Term
SARCOPLASMIC RETICULUM (SR)
Definition
specialized endoplasmic reticulum of a muscle cell
Term
possibly the only cell type in the adult human body with multiple nuclei
Definition
muscle cells (they're polynucleated)
Term
Muscle cells appear striated due to...
Definition
dark & light banding pattern of sarcomeres
Term
general anatomy of a muscle cell
Definition
[image]
Term
some components to how skeletal muscles work
Definition
-The motor unit
-The neuromuscular junction
-Excitation/contraction coupling
-Sarcomere structure & the sliding filament model of contraction
Term
A motor unit is comprised of...
Definition
a single motor neuron (alpha-motor neuron) and all of the muscle fibers (cells) it innervates
[image]
Term
depiction of a motor unit
Definition
[image]
Term
the number of muscle cells innervated by a single motor neuron varies depending on...
Definition
-the motor neuron you look at
-the part of the body is being controlled
Term
A typical motor neuron innervates how many muscle cells?
Definition
100 to 1,000
Term
One muscle cell is typically innervated by how many motor neurons?
Definition
1
Term
A ______ is comprised of many motor units
Definition
muscle
Term
All muscle fibers in the same motor unit are of the same type, characterized by...
Definition
-speed
-strength
-fatigability
Term
example of a muscle controlled by many motor neurons
Definition
quadriceps
Term
example of a muscle controlled by fewer motor neurons
Definition
fingers
Term
fatigability
Definition
how quickly a muscle tires out
Term
neuromuscular junction (NMJ)
Definition
specialized synapse between the somatic motor neuron’s nerve terminal and the motor end plate of the skeletal muscle cell
Term
motor end plate
Definition
small piece of plasma membrane on the skeletal muscle that receives the signal from the terminal of the motor neuron
[image]
Term
depiction of the neuromuscular junction
Definition
[image]
Term
how neurons stimulate muscle cells
Definition
An action potential propagated by the motor neuron typically results in an action potential across the muscle cell membrane
Term
excitation/contraction (E/C) coupling
Definition
Transformation of this electrical signal (in the muscle cell) into contraction of sarcomeres
Term
Anatomy of a Myofiber
Definition
[image]
Term
composition of the sarcolemma
Definition
-T (transverse)-tubules invaginate the myofibrils
-T-tubules are continuous with the sarcolemma
[image]
Term
composition of the sarcoplasmic reticulum (SR)
Definition
-Terminal cisternae are closely apposed to the T-tubules
-The SR surrounds myofibrils as a network of interconnected sarcotubules
[image]
Term
T (transverse)-tubules
Definition
-part of the sarcolemma
-invaginate the myofibrils
-continuous with the sarcolemma
[image]
Term
Terminal cisternae
Definition
-part of the sarcoplasmic reticulum (SR)
-closely apposed to the T-tubules
[image]
Term
myofibril
Definition
A subunit of striated muscle fiber that consists of successive sarcomeres. Myofibrils run parallel to the long axis of the muscle fiber, and the pattern of their filaments provides the striations characteristic of striated muscle cells.
[image]
Term
depiction of how excitation/contraction coupling occurs at the neuromuscular junction
Definition
[image]
-not shown in the picture, but the Na channels are expressed all over the membrane of that sarcolemma
Term
the neurotransmitter at the neuromuscular junction
Definition
acetylcholine (Ach)
Term
the receptor acetylcholine binds to at the motor-end plate
Definition
nicotinic acetylcholine receptors (nAChRs)
Term
DHPRs
Definition
dihydropyridine receptors
Term
RyRs
Definition
ryanodine receptors
Term
2 proteins that are critical for E/C coupling
Definition
-dihydropyridine receptors (DHPRs)
-ryanodine receptors (RyRs)
Term
dihydropyridine receptors (DHPRs)
Definition
integral membrane protein that's inserted into the membrane of the sarcolemma within the T-tubules
[image]
Term
ryanodine receptors (RyRs)
Definition
integral membrane protein inserted into the membranes of those terminal cisternae, which are part of the SR that lie very close to the T-tubules
[image]
Term
depiction of the physical coupling of the dihydropyridine receptors (DHPRs) and ryanodine receptors (RyRs) and what it does
Definition
[image]
Term
the sequence of events that leads to muscle contraction
Definition
[image]
Term
A single muscle cell contains many...
Definition
myofibrils
Term
A myofibril is comprised of...
Definition
serially-repeating sarcomeres --> striated appearance
Term
the smallest contractile unit of a muscle cell
Definition
sarcomere
Term
the filaments in a sarcomere
Definition
-Thin filaments: actin
-Thick filaments: myosin
Term
Sarcomeres shorten during muscle contraction (with or without) a change in length of their filaments
Definition
without
“sliding filament model” of muscle contraction
Term
the thin filaments in a sarcomere are based on...
Definition
actin
Term
the thick filaments in a sarcomere are based on...
Definition
myosin
Term
depiction of the components of the sarcomere
Definition
[image]
Term
2 proteins in the thin (F-actin) filaments
Definition
-tropomyosin
-troponin
[image]
Term
Z disc
Definition
the thin (F-actin) filaments attach to this, which is the boundary of the sarcomere
[image]
Term
role of tropomyosin and troponin
Definition
they detect changes in the Ca concentration, which leads to conformational changes in the thin (F-actin) filament
Term
the role of the head groups at the end of the thick (myosin) filaments
Definition
ATP hydrolysis activity
Term
how the sarcomere shorten
Definition
the thin (F-actin) filaments and thick (myosin) filaments slide past each other
Term
depiction of how all the filaments and everything else are oriented within a sarcomere
Definition
[image]
Term
A band
Definition
the length of a thick filament
[image]
Term
I band
Definition
-traverses 2 neighboring sarcomeres
-has the Z disc in the middle of it with thin filament on either side with no overlapping thick filament within the I band
[image]
Term
H band
Definition
the portion of the thick filaments that doesn't have any overlapping thin filaments
-it's essentially the very center of a sarcomere where you've only got thick filaments
[image]
Term
titin filament
Definition
acts as a spring like connector between the Z discs and the start of those thick filaments
[image]
Term
depiction of The Sliding Filament Model of Muscle Contraction
Definition
[image]
Term
Muscle contraction means shortening of...
Definition
muscle fibers (cells)
Term
Shortening of muscle cells results from...
Definition
shortening of myofibrils
Term
Shortening of myofibrils means...
Definition
movement of Z-discs closer to one another
[image]
Term
The sarcomeres shorten via...
Definition
sliding of thin filaments over thick filaments
[image]
Term
the bands in a myofibril that do not shorten during muscle contraction
Definition
A bands
[image]
Term
the bands in a myofibril that shorten during muscle contraction
Definition
-I bands
-H bands
[image]
Term
Each myosin head group has
Definition
-an ATP-binding domain
-an actin-binding domain
[image]
Term
Myosin heads will bind actin (thin filaments) only...
Definition
in the presence of Ca
[image]
Term
the 2 positions myosin head groups can exist in
Definition
-“cocked” position, relative to actin, or a
-“flexed” position, relative to actin
[image]
Term
The “power stroke”
Definition
causes the sliding of thin filaments across thick filaments
[image]
Term
The cross-bridge cycle
Definition
molecular mechanism of the sliding filament model
[image]
Term
what happens when cross-bridges attach to actin?
Definition
-power-strokes occur
-muscles contract
Term
In ______ muscle, the myosin/actin interaction is inhibited
Definition
relaxed
Term
Tropomyosin lies in...
Definition
the grooves of the actin filament
Term
why the myosin/actin interaction is inhibited in relaxed muscle
Definition
because tropomyosin, being in the groove of the actin filament, blocks the association of myosin with actin filaments
Term
the 3 differrent subunits of troponin
Definition
-Troponin I
-Troponin T
-Troponin C
Term
the C in Troponin C stands for...
Definition
calcium
Term
the sequence of events that leads to the binding of myosin with actin in a stimulated muscle
Definition
Stimulated muscle: Ca interacts with troponin C --> tropomyosin moves --> myosin associates with actin
Term
depiction of the troponin and tropomyosin associated with the actin filament
Definition
[image]
Term
depiction of how Ca causes E/C coupling & cross-bridge attachment
Definition
[image]
troponin bound to Ca pushes the tropomyosin out of the way
Term
Muscle action potential results in the release of...
Definition
Ca from the SR
Term
Intracellular Ca binds to ______, leading to a shift in the ______ molecules, thus allowing for...
Definition
troponin
tropomyosin
cross-bridge attachment (myosin/actin interactions)
[image]
Term
Multiple ______ lead to muscle contraction
Definition
cross-bridge cycles (power strokes)
Term
twitch
Definition
the smallest “quantum” of contraction: it’s the response of a muscle to a single action potential
Term
As action potential frequency increases, the muscle response is called...
Definition
summation, unfused (incomplete) tetanus, or fused (complete) tetanus
[image]
Term
depiction of types of muscle contractions and what they mean
Definition
[image] -Panel A: relatively few cross-bridges form; Ca2+i returns to baseline -Panels B & C: force (and Ca2+i) does not return to baseline between successive twitches; more cross-bridges form -Panel D: individual twitches cannot be distinguished; maximal cross-bridge activation (not a physiological state)
Term
Individual motor units respond with ______ & sometimes ______ to make muscle contractions in vivo
Definition
twitches
unfused tetanus
Term
whole-muscle movements are generally smooth & sustained, in large part due to...
Definition
asynchronous activation of multiple motor units
Term
Contraction strength vs. the number of motor units
Definition
proportional
Term
isometric contraction
Definition
when the muscle fiber stays the same length because of the weight being lifted is the same as the force applied to it
[image]
Term
recruitment
Definition
activation of more motor units to make a muscle contraction
Term
some things that affect the strength of contraction
Definition
-Number of fibers
-Frequency of stimulation
-Myofiber thickness
-Length of myofibers at rest
Term
depiction of the relationship between force and velocity of muscle fiber shortening
Definition
[image]
Term
concentric contraction
Definition
contraction in which the muscle fiber shortens while doing work
[image]
Term
eccentric contraction
Definition
lengthening of the muscle fiber while it is still doing work
[image]
Term
how muscle relaxation is an active process
Definition
because ATP is used to move Ca out of the cytosol
Term
depiction of some ways muscles make and use ATP
Definition
[image]
Term
some things muscles use ATP for
Definition
-they use Myosin ATPases for contraction -they use Ca2+-ATPases --> relaxation
Term
some ways muscles make ATP
Definition
-aerobic respiration
-anaerobic respiration
-phosphocreatine
[image]
Term
aerobic respiration in muscles uses...
Definition
oxidative phosphorylation (mitochondria)
[image]
Term
anaerobic respiration in muscles uses...
Definition
glycogenolysis and fermentation to lactate
[image]
Term
some things that determine where the ATP in a muscle comes from
Definition
-muscle type
-activity the muscle engages in
Term
when muscles are more likely to use aerobic respiration
Definition
when doing light work
[image]
Term
when muscles are more likely to use anaerobic respiration
Definition
when doing heavy work, when aerobic respiration alone isn't enough
[image]
Term
things that lead to muscle fatigue
Definition
Repeated activation of muscle fibers --> depletion of energy stores --> muscle fatigue
Term
Factors contributing to muscle fatigue
Definition
-Depletion of muscle glycogen stores -Lactic acid accumulation -Impaired E/C coupling (decreased release of Ca2+ from SR)
Term
some things that can result from muscle fatigue
Definition
-Decreased force production
-Reduced rate of rise of force
-Longer time to relax
Term
the types of motor units vary by...
Definition
-Speed of contraction
-Strength of contraction
-Fatigability
Term
the 3 types of motor units in your muscles
Definition
-SLOW (Type I)
-FAST FATIGUE-RESISTANT (Type IIA)
-FAST FATIGABLE (Type IIX)
Term
some characteristics of SLOW (Type I) muscles
Definition
-“Red fibers”
-Slow oxidative fibers
-Smaller diameter & less myosin --> less forceful contractions
-Fatigue-resistant
-High oxidative capacity
+Large capillary supply
+Many mito’s & oxphos enzymes
+High concentration of myoglobin (Mb)
Term
why SLOW (Type I) muscle has high oxidative capacity
Definition
-Large capillary supply
-Many mito’s & oxphos enzymes
-High concentration of myoglobin (Mb)
Term
some characteristics of FAST FATIGUE-RESISTANT (Type IIA) muscles
Definition
-“Red fibers”
-Fast oxidative fibers
-Medium diameter & more myosin --> intermediate forcefulness
-Fatigue-resistant
-Relatively high oxidative capacity
Term
some characteristics of FAST FATIGABLE (Type IIX) muscles
Definition
-“White fibers”
-Fast glycolytic fibers
-Large diameter & more myosin --> greatest force
-Fatigue quickly
-Low oxidative capacity (anaerobic respiration)
+Fewer capillaries & mito’s, less Mb
+Increased glycogen stores
+Increased concentration of glycolytic enzymes
Term
why FAST FATIGABLE (Type IIX) muscles have low oxidative capacity (anaerobic respiration)
Definition
-Fewer capillaries & mito’s, less Mb
-Increased glycogen stores
-Increased concentration of glycolytic enzymes
Term
depiction of what twitches and tetanus look like in the different types of muscle fibers
Definition
[image]
Term
some components of the nervous system that control skeletal muscle
Definition
-Proprioceptors in musculature
-Spinal interneurons
-Lower motor neurons
-Corticospinal (pyramidal) tract
-Extrapyramidal tract
Term
some proprioceptors in musculature
Definition
-Muscle spindle apparatus
-Golgi tendon organs
Term
some lower motor neurons that come out of the spinal cord
Definition
-alpha-motoneurons
-gamma-motoneurons
Term
components of the corticospinal (pyramidal) tract
Definition
-Motor cortex
-Spinal cord
Term
components of the extrapyramidal tract
Definition
-Cerebral cortex
-Thalamus / basal ganglia / cerebellum
-Brain stem
-Spinal cord
Term
depiction of the neural circuits that control skeletal muscle
Definition
[image]
Term
some descending tracts involved in control of skeletal muscle
Definition
-Corticospinal (pyramidal) tract
-Extrapyramidal tract
Term
corticospinal tract originates in...
Definition
the frontal lobes
[image]
Term
the alpha-motorneurons
Definition
the "somatic" motorneurons
-innervation of extrafusal muscle fibers
Term
gamma-motorneurons
Definition
innervation of intrafusal muscle fibers
Term
spinal interneurons
Definition
they make connections in the spinal cord between the alpha- and gamma-motorneurons
Term
function of muscle spindle apparatus
Definition
sensory feedback
Term
some details about the muscle spindle apparatus
Definition
-Located on intrafusal muscle fibers
-Muscle stretch --> spindle stretch --> stimulation of sensory neurons
-Increased length of muscle --> increased A.P. frequency
Term
function of the lower motor neurons
Definition
control of musculature
Term
the muscle spindle apparatus senses...
Definition
the stretch of the spindle apparatus
Term
extrafusal muscle fibers
Definition
the rodlike muscle cells that engage in contraction
Term
intrafusal muscle fibers
Definition
-part of the spindle apparatus
-not required for muscles to contract
-important for resetting the tension on the muscle spindle apparatus
Term
depiction of the muscle spindle apparatus
Definition
[image]
Term
the reflex to a stretch is...
Definition
contraction
Term
how gamma-fibers reset the tension on the muscle spindle apparatus
Definition
in response to stretches, they release acetylcholine, leading to excitatory input on the muscle spindle apparatus to reset the tension
Term
an example of a monosynaptic stretch reflex
Definition
the knee-jerk reflex
Term
depiction of the knee-jerk reflex
Definition
[image]
-not shown, but there's also gamma-motorneurons here that reach out to the intrafusal fibers on the muscle spindle apparatus and cause it to contract and return to a resting tension
Term
why the knee-jerk reaction is considered monosynaptic
Definition
because there's only 1 synapse responsible for making this happen
Term
an example of reciprocal innervation
Definition
agonist/antagonist muscles
Term
depiction of agonist/antagonist muscles
Definition
[image]
Term
why interneurons are often inhibitory
Definition
because they're GAB-ergic
Term
example of double reciprocal innervation
Definition
crossed-extensor reflex
Term
depiction of the crossed-extensor reflex
Definition
[image]
Term
the type of event the crossed-extensor reflex is
Definition
a nociceptive event; it involves nociceptors
[image]
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