Term
| When the ATP bound to a myosin head is split, the energy released is the direct cause of what? |
|
Definition
| Myosin head reseat or cocks for next power stroke. |
|
|
Term
| What is true and not true of a skeletal muscle? |
|
Definition
True:
Contains thin and thick filaments arranged in sarcomeres.
Needs an antagonistic muscle to reverse its movement.
Can produce both force (tension) and movement.
ITs thick filaments are made of myosin.
False:
Can both push and pull actively. |
|
|
Term
| Excitation-contraction coupling: Order of events |
|
Definition
1. Motor endplate depolarizes
2. AP travels over muscle cell membrane
3. AP travels down t-tubules
4. Ca2+ release through channels from terminal cisternae (lateral sacs)
5. Ca2+ pumped into longitudinal SR |
|
|
Term
| What functions as a normal on/off switch for crossbridge cycling? |
|
Definition
| The presence or absence of Ca2+ in sarcomere |
|
|
Term
| Why is the "skinned fiber" muscle preparation useful? |
|
Definition
| It allows researchers to apply reagents directly to sarcomeres. |
|
|
Term
| What is true about sarcomeres operating at length X on the graph? (maximum) |
|
Definition
| Thin filaments overlap all myosin heads but not other thin filaments. |
|
|
Term
| If you stand on one foot and hop, your calf muscle produces a single twitch. The best term for the difference in muscle function between hopping one inch and six or ten inches is: |
|
Definition
|
|
Term
| Facts about Temporal Summation: |
|
Definition
True:
Caused by a rapid sequence of AP's
Later contractions in the sequence are stronger than earlier ones
The higher the frequency of AP's, the stronger the final contraction
Very high frequency of AP's causes the strongest possible contraction
False:
Strength of contractions increase due to increasing number of motor units firing |
|
|
Term
| What would you expect from a muscle used to control fine finer movements? |
|
Definition
| Motor units contain a small number of muscle cells |
|
|
Term
| If, while sitting in the back of a lecture hall, a professor held up a $100 bill and challenged you to race for it, your leg muscles at the end of the run would be using what source for energy? |
|
Definition
|
|
Term
| What graph would represent only the active component of muscle tension due to crossbridge cycling? |
|
Definition
| A graph curves smoothly, shaped like an upside down U |
|
|
Term
| What does the oxygen debt that occurs during exercise represent? |
|
Definition
| Lactic acid built up during anaerobic respiration. |
|
|
Term
| What is true and not true of single unit (or visceral) smooth muscle? |
|
Definition
True:
Cells contract in response to being stretched
Contains actin and myosin
AP's can spread directly from one muscle to another
Crossbridge cycling is stimulated by Ca2+ from outside the cell
False:
Cells have one well-defined motor endplate per cell (like skeletal muscle) |
|
|
Term
| What is the direct function of rhodopsin in the phototransduction cascade? |
|
Definition
| To absorb photons and activate transducin |
|
|
Term
| What was Bernstein's hypothesis for estimating the resting membrane potential based on? |
|
Definition
| The Nernst equilibrium equation for potassium (Ek) and the knowledge that membranes are primary permeable to K+ at resting Vm |
|
|
Term
| What happens during AP's voltage regulated Na+ channels? |
|
Definition
| They are rapidly activated and then undergo voltage dependent inactivation |
|
|
Term
| The primary function of the utricle and saccule is: |
|
Definition
| to detect changes in static head tilt (plus head and body tilt) |
|
|
Term
| The "accommodation reflex" for focusing on near objects involves what? |
|
Definition
Involves:
The activation of the PNS
Activation of cranial nerves that regulate extraocular eye muscles
Activation of muscles that control iris constriction
Processing visual info in primary visual pathways due to attention on the object being viewed
Does not involve:
changing the cornea's curvature by contracting ciliary muscles |
|
|
Term
| For most neurons, the concentration of physiologically important ions in teh cytoplasm vs. the extracellular space is: |
|
Definition
Na is high OUT and low IN
organic anions (A-) are high IN |
|
|
Term
| Evidence supporting a function for human pheromones includes and discludes what? |
|
Definition
Includes:
Subjects displayed significant increases in fMRI signals in their amygdale during their first tandem skydive
When subjects inhaled exercise sweat they displayed increases in fMRI signals in their olfactory bulbs
Discludes:
When subjects inhaled stress sweat they showed increases accuracy in discriminating between a threatening face and a non-threatening face
Subjects displayed significant increases in fMRI signals in their amygdale when they inhaled stress sweat |
|
|
Term
| What are properties of mammalian olfactory receptors (OR's) and what are not: |
|
Definition
Properties:
The binding of odorant molecules to OR's ultimately depolarizes the ORC
Humans have about 340 different OR's
Dogs have a very keen sense of smell because they have billions of ORC's
Mice have about 1000 different OR's
Not true:
Each ORC expresses a diverse combinatorial array of OR's |
|
|
Term
| What makes an end-plate potential (EPP)? |
|
Definition
| The presynaptic release of Ach leading to a 50mV depolarization of a postsynaptic muscle fiber |
|
|
Term
| What is the major difference between EPSPs and IPSPs? |
|
Definition
| EPSPs are produced by excitatory neurotransmitters whereas IPSPs are produced by inhibitory neurotransmitters |
|
|
Term
| Why is the GHK equation better than the Nernst equilibrium equation at predicting Vm? |
|
Definition
| Includes terms for the ratio of Na to K permeability and the concentrations of sodium inside and outside a neuron |
|
|
Term
| Why is spatial and temporal summation of EPSP's in the CNS neurons important? |
|
Definition
| A single EPSP is too small to cause the postsynaptic neuron to depolarize and reach threshold for initiating APs |
|
|
Term
| Synaptic transmission at the NMJ will be affected by what? |
|
Definition
Will be affected by:
Inhibitors of AChE
Removing Ca from the synaptic cleft
Antagonists of nicotinic Ach receptors
Inhibitors of synaptic vesicle exocytosis
Will not be affected by:
Antagonists of glutamate receptors |
|
|
Term
| For what important function do axons of neurons in the CNS vestibular nuclei provice sensory info to other cranial nerve nuclei? |
|
Definition
| To control extrinsic eye muscles |
|
|
Term
| What associations are correct and incorrect for the cranial nerves? |
|
Definition
Correct:
CN II and sensory (vision)
CN III and motor (extrinsic muscles of the eye)
CN V and motor (muscle of mastication)
CN VIII and sensory (hearing and proprioception)
Incorrect:
CN XII and motor (trapezius and sternocleidomastoid muscle) |
|
|
Term
| Olfactor signal transduction in ORCs involves and does not involve what? |
|
Definition
True:
Activation of Ca-regulated Cl channels and chloride efflux
Odorant molecule binding to GPCRs
Opening of cAMP regulated Ca/Na channels and ORC depolarization
Activation of adenyl cyclase III and synthesis of cAMP
Does not involve: Activation of phospholipase C and generation of DAG and IP3 |
|
|
Term
| What describes the property of ossicles in the middle ear? |
|
Definition
| They transmit vibrations from teh eardrum to the oval window and they produce a 20-fold amplication in vibration amplitude from the tympanic membrane to the oval window |
|
|
Term
| What is observed and not observed when recording APs from an optic nerve in response to light stimuli of increasing intensity? |
|
Definition
Observed:
APs are short, with durations of 1 to 2msec
APs are propagated in all or nothing manner
When stimulus intensity is increased, AP firing frequency increases
Not observed: increasing stimulus intensity increases the amplitude of APs |
|
|
Term
| Why can the auditory apparatus respond to sounds of different frequencies? |
|
Definition
| The basilar membrane is narrow and stiff at the oval window vs. wide and floppy at the helicotrema (atrex) |
|
|
Term
| The activation of which voltage regulated channel is required immediately before synaptic vesicle exocytosis? |
|
Definition
| Voltage dependent N type Ca Channel |
|
|
Term
| Which of the following is involved and not involved during mechanotransduction in hair cells? |
|
Definition
Involved:
Tension on tip links made of cadherin
Calcium influx through MT channels
Release of neurtransmitter at synapses between hair cells and afferent nerves
Mechanical bending of hair cell sterocilia
Not involved:
Ca efflux through N type Ca channels |
|
|
Term
|
Definition
| The ability of cochlear afferents to phase-lock APs when the basilar membrane vibrates at frequencies greater than 400 Hz. |
|
|
Term
| Which of the following is correct and incorrect? |
|
Definition
Correct:
Cerebellum and fine tuning of voluntary and involuntary motor behavior
Sub-genu gyrus and depression
Broca's area and speech production
Primary somatomotor cortext and control of voluntary motor movement
Incorrect:
Hypothalamus and excessive-compulsive behavior |
|
|
Term
| What statements are true and which are false? |
|
Definition
True:
Hearing loss is a major nervous system disorder, especially in the elderly population
Alzheimer's disease is one of the most costly nervous system disorders
The USA spends more than 500 billion dollars annually to treat mental illnesses
Mental illnesses are the leading cause of suicide in the US
False:
1 in 7 Americans will have some type of nervous system disorder in their life |
|
|
Term
| What does the physiology of GABAergic synaptic transmission include? |
|
Definition
| Modulation of GABAa receptors by benzodiazepines, activation of postsynaptic GABAb receptors produces IPSPs by increasing K efflux, clearance of GABA from the cleft by transporters in presynaptic terminals and glial cells |
|
|
Term
| What is the key Ca sensor for synaptic vesicle exocytosis? |
|
Definition
|
|
Term
| What is the physiological state of rod photoreceptors in the dark? |
|
Definition
| Depolarized and releasing glutamate |
|
|
Term
| What accurately describes the NMJ? |
|
Definition
The basal lamina (basement membrane) anchors AChE in the synaptic cleft.
Postsynaptic junctional folds contain high densities of AChRs at their crest.
The motor axon branches as it innervates the NMJ and makes many separate active zones.
Presynaptic terminals contain "docked" (Front row) synaptic vesicles. |
|
|
Term
| Beginning with the 1st order photoreceptors of the visual pathway, the 2nd and 3rd order cells are what? |
|
Definition
| Retinal bipolar neurons and ganglion cells |
|
|
Term
| What is the primary function of the cupula? |
|
Definition
| To enclose the stereocilium and kinocilium and aid in their deflection by forces exerted by endolymph. |
|
|
Term
| When hair cell stereocilia are deflected to pull on the tip links between adjacent stereocilia, what happens next? |
|
Definition
| Ca permeable MT channels open and the hair cell depolarizes |
|
|
Term
| A lesion of the visual pathways at the optic chiasm which only destroys crossing ganglion cell axons from the eyes produces what visual field deficit? |
|
Definition
| Loss of the temporal half of the visual field for both eyes |
|
|
Term
| On-center ganglion cells increase their AP firing when a light stimulus does what? |
|
Definition
| Selectively activates the center region of the receptive field |
|
|
Term
| The functions of the extrinsic eye muscle includes and does not include what? |
|
Definition
Includes:
Change the position of the eye to project visual images on the fovea.
Coordinate eye movement for upward gaze.
Coordinate eye movement for downward gaze.
Coordinate eye movements for seeing moving objects.
Does not include:
Changing the curvature of the lens |
|
|
Term
| Our ability to perceive color requires and does not require what? |
|
Definition
Requires:
Activation of opsins by light of different wavelengths.
Light dependent conversion of 11-cis retinal to all-trans retinal
Activation of transducin
S-, M- and L-cones
Does not require:
Regulated opening and closing of cGMP-dependent K channels in photoreceptor outer segments |
|
|
Term
| What can abnormal functioning of the oculomotor system result in? |
|
Definition
| Blurred vision, abnormal depth perception, and double vision |
|
|
Term
| The presynaptic action of norepinephrine involves and does not involve what? |
|
Definition
Involves:
a2 receptors
modulation of Ca influx into the presynaptic terminal
B2 autoreceptors
G-protein signaling
Does not involve:
presynaptic ionotropic receptors |
|
|
Term
| What is the primary function of Schwannn cells? |
|
Definition
| making individual segments of myelin along a peripheral nerve fiber |
|
|
Term
| The critical period of visual system development for mammals starts 1 week after birth and lasts a month. If the left eye of a cat is sutured closed for the entire 3rd and 4th week after birth, what is the result? |
|
Definition
| Axon terminals of LGN neurons connected to ganglion cell axons from the deprived eye fail to develop and the cat is essentially blind in the eye that was sutured closed. |
|
|
Term
| A single dorsal root ganglion? |
|
Definition
| contains the cell bodies of pseudo-unipolar sensory neurons |
|
|
Term
| What is happening to the conductance of voltage-regulated Na channels when an axon's VM is maximally depolarized at the peak of an AP? |
|
Definition
| It begins decreasing because Na channels begin to inactivate. |
|
|
Term
| The mammalian olfactory epithelium contains and does not contain what? |
|
Definition
Contains:
mucus layer
dividing stem cells
olfactory receptor cells (ORCs)
Bowman's glands
Does not contain: dendrites |
|
|
Term
| What are and are not properties of cochlear cells? |
|
Definition
Properties:
When destroyed they do not regenerate
They have a very large VM (about -140mV) at rest
They die at progressively faster rates in elderly people
Regular exposure to sounds greater than 100dB can cause permanent damage to hair cells
Not property: their MT channels are inactivated by calcium |
|
|
Term
| What is the function of kinesin? |
|
Definition
| Transport cargo along microtubules in anterograde direction |
|
|
Term
| Our ability to perceive complex sounds is because the basilar membrane does what? |
|
Definition
| simultaneously vibrates at multiple locations along its length |
|
|
Term
| fMRI has show significant differences between men and women in perceiving testosterone like vs estrogen like pheromones. These results show and do not show what? |
|
Definition
Show:
Females perceive pheromone signals in their anterior hypothalamus
Males perceive pheromone signals in their posterior hypothalamus
Females detect both male and female pheromones (the mate and competition)
Males detect mainly female pheromones
Does not show: males mainly detect testosterone like pheromones |
|
|
Term
| Voltage regulated Na channels display what properties? |
|
Definition
They contain 4 domains that have similar structures which fold together to form a channel.
Each of its 4 domains contains a region that contributes to the channels ion pore.
Each domain contains a voltage sensing region that responds to changes in Vm.
Each Na channel has just one inactivation gate that blocks Na conductance following channel activation |
|
|
Term
| In most neurons, the concentration of physiologically important cations in the cytoplasm versus the extracellular space is: |
|
Definition
| Na+ is high OUT, and low IN |
|
|
Term
| The depolarization threshold for initiating an AP in a CNS neuron is about: |
|
Definition
|
|
Term
| How many synaptic contacts are made on a typical CNS neuron? |
|
Definition
|
|
Term
| Using the GHK equation, what is the approximate membrane potential for a neuron under the following conditions: [K+]o=5mM, [K+]i=150mM, [Na+]o=450mM, [Na+]i=5mM, and alpha = 0.08 |
|
Definition
|
|
Term
| What is and is not observed when recording APs from an optic nerve in response to light flashes of increasing intensities? |
|
Definition
Observed:
APs are very short; duration of 1msec
APs are initiated in all or nothing manner
When stimulus intensity is increased, the frequency of APs incrases
When stimulus intensity is increased, the amplitude of APs remain constant
Not observed:
When stimulus intensity is increased, the Amplitude of APs increased (not true) |
|
|
Term
| At resting Vm of -60mV, the plasma membrane of a neuron is: |
|
Definition
| Much more permeable to K+ and Na+ |
|
|
Term
| Bernstein based his hypothesis for estimating the resting Vm on what? |
|
Definition
| The Nernst equilibrium equation for potassium and the knowledge that neuronal membranes are primarily permeable to K+ at resting Vm |
|
|
Term
| The GHK equation is better than the Nernst equilibrium equation at predicting Vm because: |
|
Definition
| it includes terms for the ratio of Na+ to K+ permeability and the concentration of sodium inside and outside a neuron |
|
|
Term
| What associations are correct and incorrect? |
|
Definition
Correct:
CN II and sensory (vision)
CN III and motor (extrinsic eye muscle)
CN V and motor (muscle of mastication)
CN VIII and sensory (hearing and proprioception)
Incorrect:
CN XII and motor (trapezius and sternocleidomastoid muscle) |
|
|
Term
| What are properties of cranial nerves? |
|
Definition
Properties:
Most CNs exit/enter the CNS in the midbrain, pons or medulla.
Some CNs possess both sensory and motor components
CNs are major pathways transmitting sensory info from the PNS to the CNS
CNs are major pathways transmitting motor info from the CNS to the PNS
Incorrect: the sensory components of most CNs carry information directly from the body's 31 dermatomes into the CNS |
|
|
Term
| What is observed and not observed when reading APs from Horse Shoe Crab's optic nerve in response to light stimuli of increasing intensity? |
|
Definition
Observed: APs are short with durations of 1-2msec
APs are propagated in an all or nothing manner
When stimulus intensity is increased, AP firing frequency increases
Not observed:
Increasing stimulus intensity increases the amplitude of APs
Increasing stimulus intensity increases the width of APs |
|
|
Term
| What associations are correct and incorrect? |
|
Definition
Correct:
Cerebellum and fine tuning of voluntary and involuntary motor behavior.
Sub-genu gyrus and depression
Broca's area and speech production
Primary somatomotor cortex and control of voluntary motor movement
Incorrect: hypothalamus and addiction and compulsive behavior |
|
|
Term
| The dorsal root ganglion at a specific segmental level contains: |
|
Definition
| the cell bodies of pseudo-unipolar sensory neurons for that segment |
|
|
Term
| What is a major difference between Schwann cells and oligodendrocytes? |
|
Definition
| Oligodendrocytes myelinate multiple axons whereas Schwanns myelinate just one axon |
|
|
Term
| What are considered physiological boundaries for the change in Vm during the AP? |
|
Definition
|
|
Term
| What voltage regulated process contributes to the AP or neurotransmitter release and what does not? |
|
Definition
Contributes:
activation of Na+ channels
inactivation of Na+ channels
activation of K+ channels
activation of N-type Ca2+ channels
Does not contribute: inactivation of Cl- channels |
|
|
Term
| How does the amplitude of an EPP compare to that of EPSP? |
|
Definition
|
|
Term
| What is a major difference between EPSPs and IPSPs? |
|
Definition
EPSPs depolarize
EPSPs hyperpolarize postsynaptic neurons |
|
|
Term
| What is the voltage regulated channel required for synaptic vesicle exocytosis? |
|
Definition
|
|
Term
| Spatial and temporal summation of EPSPs in CNS neurons is important because: |
|
Definition
| a single EPSP is too small to cause the post synaptic neuron to depolarize and reach threshold for initiating an AP |
|
|
Term
| The amplitude of EPPs at the NMJ can be affected by: |
|
Definition
Affected by:
curare, the presence or absence of extracellular Ca2+, neostigmine, increasing the quantal content in synaptic vesicles
Not affected by:
APV |
|
|
Term
| Signaling mechanisms responsible for slow EPSPs mediated by metabotropic glutamate receptors (mGluRs) include: |
|
Definition
Include:
Activation of adenylate cyclase by G-proteins
Synthesis of cyclic AMP
Activation of protein kinase A by cAMP
Phosphorylation of K+ channels
Does not include: activation of phosphodiesterase by G-proteins |
|
|
Term
| Properties of the NMDA-type glutamate ionotropic receptors: |
|
Definition
Properties:
its activation is required for the induction of LTP
Its ion channel is permeable to Ca2+
At Vm = 60mV, its ion channel is blocked by Mg2+
It is activated by glutamate plus membrane depolarization
Not a property: it is activated by glutamate plus membrane hyperpolarization |
|
|
Term
| The amplitude of an EPP can be altered by: |
|
Definition
Altered by:
curare
extracellular concentration of Ca2+
neostigmine
changing the quantal content of synaptic vesicles
Not altered by: N-methyl D-aspartate (NMDA) |
|
|
Term
| What is the major difference in ion selectivity between the AMPA- and NMDA-type glutamate receptors? |
|
Definition
| The NMDA receptor is much more permeable to Ca2+ than the AMPA receptor. |
|
|
Term
| In the context of synaptic transmission, what does release probability (Pr) refer to? |
|
Definition
| The probability of transmitter release when an AP invades the presynaptic terminal |
|
|
Term
| Our ability to perceive color requires: |
|
Definition
Requires:
The different opsins respond to light of different wavelengths
Light-dependent isomerization of 11-cis retinal
Activation of transducin
S-, M- and L-cones
DOes not require: conversion of ATP to cyclic AMP |
|
|
Term
| Abnormal functioning of the oculomotor system can result in: |
|
Definition
Results in: blurred vision, loss of depth perception, double vision, loss of control of pupil's opening
Does not result in: loss of control of cornea's shape by extrinsic eye muscles |
|
|
Term
| Visual information from both eyes is represented in: |
|
Definition
Represented in: optic tract, axon projections from lateral geniculate nucleus, optic radiations, primary visual cortex on left side of brain
Not represented in: optic nerve |
|
|
Term
| Sound waves are transmitted from the tympanic membrane to the oval window of the cochlea by: |
|
Definition
| the movement of ossicles in the middle ear |
|
|
Term
| The tonotopic response of the basilar membrane to sounds of different frequencies is due to: |
|
Definition
| the basilar membrane being narrow and stiff at its base and wide and floppy at its apex |
|
|
Term
| Structures of the cochlea: |
|
Definition
Scala vestibuli, scala tympani, basilar membrane, tectorial membrane
NOT a structure: scala malleus |
|
|
Term
| The primary auditory cortex is located where? |
|
Definition
| the superior lip of te temporal lobe |
|
|
Term
| The ability of the visual system to focus images on the retinal involves: |
|
Definition
Involves:
Accommodation reflex for objects closer than nine meters
Flattening the lens by suspensory ligaments for distant objects
Convergence of the eyes on the image by the action of rectus muscles
Control of suspensory ligaments by the Edinger-Westphal nucleus
Does not involve: inhibition of rods and cones by ganglion cells |
|
|
Term
| A complete lesion of the optic tract between the optic chiasm and the lateral geniculate nucleus on the right side of the brain will produce what visual field deficit? |
|
Definition
| Loss of the temporal (left) half of the visual field in the left eye and the nasal (left) half of the visual field in the right eye |
|
|
Term
| What is the physiological status of a rod in very low light? |
|
Definition
| Depolarized and releasing glutamate |
|
|
Term
| In the phototransduction cascade, the function of transducin is to: |
|
Definition
| activate phosphodiesterase and decrease cyclic guanosine monophosphate levels |
|
|
Term
| What is located in the retina? |
|
Definition
Located: horizontal cells, on and off bipolar cells, cones and rods, on and off ganglion cells
Not located in retina: outer and inner geniculate neurons |
|
|
Term
| Functions of the semicircular canals: |
|
Definition
Functions: pairs of canals work together to detect changes in angular acceleration, the transduction of vestibular information involves the release of glutamate from hair cells, they provide vestibular info to the CNS to coordinate eye movements and maintain posture
Not a function: transduction of mechanical bending of hair cells into electrical activity is achieved by the opening and closing of K+ channels; the conversion of mechanical bending of hair cell stereocilia into electrical activity is achieved by opening/closing of Na+ channels |
|
|
Term
| What is the primary function of the cupula? |
|
Definition
| to enclose stereocilium and kinocilium and help in their deflection by fluid florces in the semicircular canal |
|
|
Term
| The primary function of the otolith organ is to: |
|
Definition
| detect changes in linear acceleration |
|
|
Term
| What cranial nuclei receive vestibular info and control eye movement? |
|
Definition
| The trochlear nucleus, the oculomotor nucleus and the abducens nucleus |
|
|
