Chapter 5 Med Phys
Given the following permeabilities, extracellular fluid (ECF) concentrations, and intracellular fluid (ICF) concentrations for Na+, K+ and Cl-, calculate the resting membrane potential of a hypothetical cell: ECF: [Na+] = 145 mM; [K+] = 5 mM; [Cl-] = 100 mM ICF : [Na+] = 4 mM; [K+] = 160 mM; [Cl-] = 17 mM PK+ = 1; PNa+ = 0.05; PCl- = 10
-49 mV
Four steps of the cross bridge cycle
1. Attachment of cross bridge to thin filament 2. Movement of cross bridge, producing tension in the thin filament and dissociation of ADP and Pi from cross bridge 3. Detachment of the cross bridge from the thin filament 4. Re-energizing the cross bridge by hydrolysis of ATP
Beginning from the alert state, put these EEG patterns in the order that a person typically goes through when falling asleep and progressing through one cycle of sleep. Start with the earliest at the top of the list.
1. BETA 2. ALPHA 3. THETA 4. DELTA 5. REM
Olfactory bulb cells
1. Odorant molecules enter the nose 2. Odorant molecules dissolve in and diffuse through the mucous covering the olfactory epithelium 3. Odorant molecules bind to cillia 4. Stimulated receptors activate a G protein mediated pathway that increases cAMP levels 5. Nonselective cation channels are opened and olfactory epithelium cells depolarize
Put the steps of long-term potentiation into the correct order. Start with the earliest at the top.
1. Pre-synaptic neurons fire action potentials at a high frequency 2. Voltage gated calcium channels open and calcium enters the presynpatic neuron 3. Glutamate is released, diffuses across the cleft, and binds to both AMPA and NMDA receptors on the post-synaptic membrane 4. Sodium ion entry through AMPA receptors depolarizes the membrane by 20-30 mv and moves magnesium ions out of the channels 5. Calcium enters the post-synaptic cell through NMDA receptor channels and activates a second messenger cascade 6. Multiple kinases and a retrograde messenger mediate a long-term increase in pre-synaptic glutamate release and post-synaptic glutamate sensitivity.
Place the following structures in the order they would be penetrated by a surgeon accessing the brain to remove a tumor. Start with the first structure at the top of the list.
1. SKIN 2. SKULL BONE 3. DURA MATER 4. ARACHNOID MATTER 5. SUBARACHOID MATTER 6. PIA MATTER
If you hold out your hands and a friend gradually piles books on them one at a time, rank the following in the order that they would be recruited to contract as the total load becomes increasingly heavy (first ones on top).
1. Slow oxidative fibers 2. fast oxidative-glycolytic fibers 3.fast glycolitic
Arrange these events in the order that most logically explains how a cell goes from having no membrane potential to having a steady negative resting membrane potential. Start with the earliest step at the top.
1. The Na+/K+ ATPase pumps moves out Na and brings K into the cell, setting up concentration gradients across the membrane 2. Due to permeability difference, there is a greater net movement of K out of the cell than Na 3. The membrane potential becomes negative, approaching the K equilibrium potential 4. Equal leaks of Na and K are offset by the continued activity of Na/K-ATPase pump
In a given night, about how many sleep cycles does a typical individual go through?
4-5
is a neuromuscular disorder caused by autoimmune destruction of nicotinic ACh-receptor proteins at the neuromuscular junction. It is characterized by muscle fatigue and weakness that worsens as the muscle is used. Multiple choice question.
Myasthenia gravis
Velocity of action potential propagation is determined by which of the following?
Myelination Axon diameter
Which of the following are receptors for the neurotransmitter glutamate?
N-methyl-D-aspartate (NMDA) Alpha-amino-3 hydroxy-5 methyl-4 isoxazolepropionic acid (AMPA)
Match the stage of sleep with the EEG pattern with which it is associated.
N1- THETA N2- sleep spindles and k complexes N3- DELTA REM- BETA-RHYTHM-LIKE PATTERN
What gaseous neurotransmitter is produced from L-arginine by nitric oxide synthetase?
NO
The ions that enter a neuron and cause the depolarization phase of a typical action potential are ions.
Na
When a neuronal membrane is depolarized by a stimulus, which voltage-gated channels typically open the fastest?
Na
The predominant ions in the extracellular fluid are ______, and the predominant ions in the intracellular fluid are ______.
Na+ and Cl-; K+ and phosphate compounds
Which of these options stimulate secretion by orexin neurons in the hypothalamus? Multiple select question.
Negative energy balance Limbic system activity associated with anger or fear Excitatory inputs from the suprachiasmatic nucleus
Which is NOT true about regulation of smooth muscle cells by autonomic neurons? Multiple choice question.
Neurotransmitter receptors are found only at well-defined motor end plates.
The main types of antidepressant drugs act by interfering with which of the following?
Neurotransmitter reuptake Neurotransmitter degradation
Excitatory synaptic activity is enhanced throughout the brain when brainstem neurons of the reticular activating system release which neuromodulatory monoamines?
Norepinephrine Histamine Serotonin
Which 3 of the following are true about action potential conduction in myelinated axons?
Propagation occurs without a decrease in action potential size. It is called called saltatory conduction. It is faster than in unmyelinated axons.
Which of these options are somatic sensory receptors?
Proprioceptor Thermoreceptor Skin pressure receptor
Which of the options are correctly identified as lipid neurotransmitters?
Prostaglandins Endocannabinoids Leukotrienes Thromboxanes
Which are terms used to describe the stage of sleep in which dreams most commonly occur? Multiple select question.
REM Rapid eye movement Paradoxical
During which stage of sleep is the brain's activity most like that of an alert, awake individual?
REM sleep
Which of these are receptors for touch and pressure in the skin?
Ruffini corpuscle Merkel's corpuscle Pacinian corpuscle Meisner's corpuscle
Which structures senses straight line (linear) accelerations of the head, as might occur when riding in an elevator or holding your head at a particular angle with respect to gravity (like bent over to tie a shoe)?
Saccule Utricle
Some chemicals stimulate taste receptors when they bind to surface membrane proteins. Chemicals of which taste category stimulates receptors by passing through channels in the membrane?
Salty
AROUSAL =
THALMUS
Which is a true statement regarding the voltage-gated Na+ and K+ channels that mediate neuronal action potentials?
The Na+ channels have inactivation gates, but the K+ channels do not.
Which of the following is true about graded potentials?
The flow of charge decreases with distance.
During action potential propagation, when an action potential is occurring in one patch of membrane what induces the neighboring patch of membrane to depolarize to threshold?
The flow of local positive current from the depolarized patch to the neighboring patch of membrane.
Consider an experimental set-up with two fluid-filled chambers that are separated by a plasma membrane with open K+ channels but no other ion permeability. If you were to add 100 mM of NaCl into side 1 and 100 mM of KCl into side 2, what would you expect to happen?
The membrane will develop a membrane potential that is positive on side 1 compared to side 2.
The following statements relate to movement of ions during an action potential. Which are true?
The number of ions that cross the membrane during an action potential is extremely small compared to the total number of ions in a cell. With repeated action potentials, concentration gradients for Na+ and K+ would eventually dissipate without the action of the Na+/K+-ATPase pump.
Which of the following are mechanisms of physiological tolerance to a substance? Multiple select question.
The presence of the substance stimulates the synthesis of enzymes that degrade it. The presence of the substance inhibits elements of the signal transduction pathway leading to the drug's effect. The presence of the stimulus causes downregulation of receptors that respond to it.
Which is TRUE regarding the effect of the Na+/K+-ATPase pump on the membrane potential of excitable cells?
The pump has a minor electrogenic effect that directly contributes to the negative value of the resting membrane potential.
Which of these influences the velocity at which a whole muscle shortens?
The types of motor units that are recruited The number of muscle fibers recruited The frequency of action potentials activating individual motor units The load on the muscle
Which statement is true about sensory neural pathways?
They are afferent pathways generally formed by chains of three or more neurons that carry information to the central nervous system.
Action potentials tend to travel in only one direction along an axon for which two reasons?
They begin propagating at one end of an axon, and not in the middle Refractoriness of the region of membrane where an action potential has just occurred prevents a propagating action potential from reversing direction
Which are similarities between skeletal muscle and cardiac muscle?
They both have a T-tubule system They both are striated, and have sarcomeres They both have troponin and tropomyosin, and those proteins serve the same functions in each
True or false: Graded potentials can either depolarize or hyperpolarize the membrane potential.
True
True or false: Most cells have resting membrane potentials that are negative on the inside compared to the outside. True false question.
True
True or false: Olfactory neurons become activated through a second messenger system.
True -cAMP system
True or false: The ability to transfer language functions from one area of the brain to another ends around puberty.
True There is a critical period for development of language skills that ends around puberty. (See page 252.)
What is the term describing the contraction and relaxation that occurs in a muscle fiber after it is stimulated by a single action potential?
Twitch
Which of the five primary taste categories involves the stimulation of taste hairs by glutamate and similar amino acids? Multiple choice question.
Umami
Where in the brain is white matter located? Multiple choice question.
Deep to the cortex and surrounding the subcortical nuclei.
Which of these are symptoms of depressive disorder?
Disturbed sleep Irritability Loss of energy Pervasive feeling of sadness Decreased appetite
Which of the following does NOT influence the encoding of stimulus intensity?
Duration of the stimulus
The sarcoplamic reticulum is homologous to the ______ found in most cells. Multiple choice question.
ER
Which of these are functions regulated by neural centers in the hypothalamus?
Eating behavior Sexual behavior Temperature control Drinking behavior
Which of the following may be attributed to the effects of endogenous opioids?
Exercise euphoria Eating and drinking behavior Pain relief
True or false: A fundamental physical principle is that charges of the same type (such as 2 positive charges) attract each other, while charges of opposite types (positive and negative) repel each other.
False
True or false: A large number of ions are required to cause the large fluctuation in membrane potential during an action potential; without the action of the Na+/K+-ATPase pump, the concentration gradients for Na+ and K+ would be significantly altered by a single action potential.
False
True or false: All sensory signals are consciously perceived.
False
True or false: The neuronal membrane is much more permeable to sodium than potassium during rest because there are more ion channels for sodium. True false question.
False
True or false: The number of anions floating freely in the bulk solution inside of excitable cells is greater than the number of cations in the bulk solution, which is why the resting membrane potential is negative.
False
True or false: Whether a synapse is excitatory or inhibitory is determined by what neurotransmitter is released from the presynaptic cell. True false question. True
False- Whether a synapse is excitatory or inhibitory is determined by the type of postsynaptic ion channel influenced by the neurotransmitter.
Which lobes of the cerebral cortex contain centers involved in the technical aspects of language understanding and expression? Multiple select question.
Frontal Temporal Parietal
Which of the association areas of the cortex are important in sensory processing? Multiple select question.
Frontal lobe association area Temporal lobe association area Parietal lobe association area Occipital lobe association area
Which of the following are categorized as amino acid neurotransmitters?
Gamma-aminobutyric acid (GABA) Glycine Glutamate
Given the concentration gradients and relative membrane permeabilities for Na+, K+, and Cl-, the resting membrane of a cell can be calculated using the ______ equation
Goldman-Hodgkin-Katz (GHK)
Mechanoreceptors that monitor tension on tendons are called organs. Listen to the complete question
Golgi tendon
Monique lives on a busy street near a hospital. Her first day there she constantly noticed that ambulances were driving by with their sirens going. After a few days, she stopped paying attention to the ambulances. This is an example of what type of conscious experience? Multiple choice question.
Habituation
Which two of the following are defined as altered states of consciousness? Multiple select question.
Hallucinating Delusional
Which three of these options are typical symptoms of the disorder schizophrenia?
Hallucinations Catatonia Delusions
Which two regions of the brain are centers involved in mediating emotional responses? Multiple select question.
Hypothalamus Limbic system
During cross-bridge cycling when Ca2+ remains present in the cytosol, which step of the cycle happens immediately after the energizing of the cross-bridge?
Attachment of the cross-bridge to actin
Velocity of action potential propagation is determined by which of the following?
Axon diameter Myelination
Which best describes a neuromodulator? Multiple choice question.
A compound that indirectly alters the effectiveness of a synapse by altering release of, or responsiveness to, a neurotransmitter.
Which best describes the process called "repolarization?"
A neuron is returning from the peak of its action potential toward its resting potential.
Which region of the body would have the greatest sensory acuity?
A region with large numbers of small sensory units
Which best defines the term "muscle fiber?"
A skeletal muscle cell
In parasympathetic pathways, the main neurotransmitter released by presynaptic neurons is BLANK and the main neurotransmitter released by postsynaptic neurons is BLANK
ACH FOR BOTH
Which of the following are proposed functions of astrocytes?
Absorption of K+ from the extracellular fluid Stimulate the formation of tight junctions between the cells that constitute the blood-brain barrier
What enzyme is responsible for the inactivation of acetylcholine at the synaptic cleft?
Acetylcholinesterase
Which of these explains why an action potential is able to propagate along the full length of an axon?
Action potentials are regenerated in each patch of membrane by depolarizing local currents arriving from previously-depolarized patches of membrane.
With reference to muscle physiology, which best defines the term "contraction?"
Activation of cross-bridge cycling
Removal of neurotransmitters from synapses occurs by which of the following mechanisms? Multiple select question.
Active transport into nearby cells, such as glial cells Diffusion away from the synapse Active transport back into the presynaptic terminal Enzymatic transformation into inactive substances
Which of the following inhibits secretion by orexin neurons?
Adenosine
Which of the following are purines that are co-released from neurons and act as neuromodulators?
Adenosine ATP
Which of the following has sensory receptors at one end of the cell?
Afferent neurons
In an experiment with an artificial cell, the equilibrium potentials for ions X+, Y- and Z+ are +50 mV, -50 mV, and +5 mV, respectively. If the cell is equally permeable to ions X+ and Y-, but 10 times more permeable to ion Z+ than to ion Y-, which statement is most likely true?
All three ions have higher concentrations outside the cell than inside, and the resting membrane potential is positive.
Which of the following are receptors for the neurotransmitter glutamate?
Alpha-amino-3 hydroxy-5 methyl-4 isoxazolepropionic acid (AMPA) N-methyl-D-aspartate (NMDA)
Which pathway in carries sensory information about pain and temperature? Multiple choice question.
Anterolateral system
Which system crosses in the spinal cord? Multiple choice question.
Anterolateral system
Which of the following are components of a taste bud? Multiple select question.
Basal cells Gustatory cells Microvilli (taste hairs)
Which of the following are classified as neuropeptide neurotransmitters/neuromodulators? Multiple select question.
Beta-endorphin Enkephalin Dynorphin
Identify the five primary taste sensations.
Bitter Umami Sour Sweet Salty
What fuel substrates are used to produce ATP by oxidative phosphorylation in skeletal muscle fibers? Multiple select question.
Blood fatty acids Blood glucose Glucose from muscle glycogen
Which two brain centers are involved in mediating the technical aspects of understanding and expressing language?
Broca's area Wernicke's area
Habituation is thought to involve a decreased influx of
Ca+2, Ca, or Ca2+
What initiates the release of calcium from the sarcoplasmic reticulum in cardiac muscle cells?
Calcium ions that enter from the extracellular fluid when L-type Ca2+ channels open bind to ryanodine receptors on the sarcoplasmic reticulum.
Which of the following statements about nitric oxide (NO) are true?
Causes an increase in the concentration of cyclic GMP in target cells Mediates penile erection Acts as a neurotransmitter
What are the two major divisions of the forebrain?
Cerebrum Diencephalon
Two fluid-filled experimental chambers are separated by a plasma membrane that has open Cl- channels but no other ion permeability. Into side 1 you put 200 mM NaCl and into side 2 you put 100 mM KCl. Which of the following will occur?
Cl- will flow from side 1 to side 2 and the membrane will develop a membrane potential that is positive on side 1 and negative on side 2.
What molecule can be used by muscle to recharge ADP into ATP during short intense bouts of exercise?
Creatine phosphate
Which is generally true regarding how postsynaptic potentials initiate action potentials at synapses between neurons? Multiple choice question.
Individual EPSPs are small, so initiating an action potential requires the summation of multiple excitatory inputs within a short time period.
The EEG patterns of NREM sleep occur in 3 stages: N1, N2, and N3. As an individual progresses from the N1 to N2 stage, and N2 to N3 stage, what happens to the frequency and amplitude of the EEG pattern?
It becomes lower frequency, and larger amplitude.
Which is true about signaling by nitric oxide (NO)?
It diffuses into target cells and activates guanylyl cyclase.
Which of the following statements about norepinephrine are true? Multiple select question.
It is a biogenic amine. It is a neurotransmitter. It is a catecholamine.
Which statement best describes the organization of the somatosensory cortex?
It is located behind the central sulcus, and is a regional map of the body with the feet represented medially and the face and hand laterally. Select a concept resource to continue.
Which ion species are in higher concentration in the cytosol of neurons than in the extracellular fluid? Multiple select question.
K+ Phosphate ions
Which four of the following are TRUE during the relative refractory period?
K+ is continuing to flow out of the cell. Voltage-gated K+ channels are resetting to the closed position. Some voltage-gated Na+ channels are closed while some are still inactivated. Voltage-gated Na+ channels are resetting from the inactivated to the closed position.
Which of the following chemicals is NOT known to stimulate the receptors for pain (nociceptors)?
Kinesin
In which of the following will the speed of action potential propagation be fastest? Multiple choice question.
Large diameter, myelinated fibers
is the acquisition and storage of information as a consequence of experience. Multiple choice question.
Learning
What type of channels in the postsynaptic membrane open when neurotransmitters bind to them?
Ligand-gated channels
Indicate which three of the following are examples of sensory modalities.
Light Pressure Cold
Which brain structure is most important for forming the type of memories that can be put into words?
Limbic system
Besides modality, what other types of information are encoded by sensory receptors?
Location and intensity
Variations in stimulus intensity can be due to which of the following factors?
Magnitude of receptor potentials Recruitment of different numbers of afferent neurons Frequency of sensory nerve fiber firing
What two general categories are used to classify skeletal muscle fibers into distinct fiber types?
Major metabolic pathways used to make ATP Maximal shortening velocity
Which of the following increase the surface area of taste receptor cells and contain integral membrane proteins that transduce the binding of a given chemical into a receptor potential? Multiple choice question.
Microvilli
An IPSP is ______.
a graded potential in a postsynaptic cell that decreases the likelihood that the cell will reach the threshold for an action potential
The resting membrane potential is mainly due to ______.
a tiny separation of charges that collect in a thin shell tight against the inner and outer surfaces of the membrane
After the initiation of an action potential in a given region of a neuronal membrane, there is a period of time during which a second action potential cannot be stimulated no matter how strong the stimulus. This is called period.
absolute refractory
Muscarinic and nicotinic receptors are types of
acetylcholine receptors
The neurotransmitter used by somatic motor neurons is ______ and the effect on muscles is ______.
acetylcholine; always excitatory
Large, rapid, all-or-none depolarizations of neuron membrane polarity are called
action potentials
Prior to activation of a chemical synapse, many vesicles are docked on the presynaptic membrane at release regions known as
active zones
Synaptic vesicles ready to be released at chemical synapses are at locations known as ________. Multiple choice question.
active zones
The precision with which we can locate and discern one stimulus from an adjacent one is referred to as sensory
acuity
Summation occurs when ______. Multiple choice question.
additional stimuli cause graded potentials to occur in a neuron before the graded potentials from previous stimuli have died away
Caffeine inhibits the sleep state, in part by blocking ______ receptors on orexin-secreting neurons. Multiple choice question.
adenosine
Receptors that respond to norepinephrine or epinephrine are called ______ receptors. Multiple choice question. beta cholinergic
adrenergic
Because the voltage-gated K+ channels of an axon close relatively slowly, immediately after the action potential there is a period of time where the membrane is transiently hyperpolarized towards the K+ equilibrium potential; this portion of the action potential is called the ______.
afterhyperpolarization
When voltage-gated K+ channels are slow to close, the membrane potential is between the normal resting potential and the K+ equilibrium potential. This phase of the action potential is known as the , phase.
afterhyperpolarization
The toxin muscarine is classified as a(n) _______ because it binds and activates muscarinic ACh receptors.
agonist
Drugs that bind to and activate receptor proteins are called
agonists
An action potential is either generated because a stimulus is suprathreshold, or is not generated because the stimulus is subthreshold. This property of action potentials is referred to as the _-_-_ property.
all or nothing
Most skeletal muscles are composed of ______. Multiple choice question.
all three motor unit types (1, 2A, and 2X) interspersed with each other
When a relaxed individual suddenly selectively attends to a novel stimulus, their EEG pattern would switch from a predominately ______ pattern to a(n) ______ pattern.
alpha; beta
Loss of memory is called
amnesia
The term that means "the selective suppression of pain without effects on consciousness or other sensations" is
analgesia
Neurotransmitters do not stay bound to receptors indefinitely; instead, they ______.
are broken down into component parts by enzymes are transported back into the presynaptic cell via reuptake diffuse away from the synapse
Receptor potentials ______. Multiple choice question.
are graded potentials in afferent neurons
The glial cells of the nervous system
are non-neuronal cells that provide physical and metabolic support to neurons
A term that is often used synonymously with "sensory pathway" is ______. Multiple choice question.
ascending pathway
The glial cells that promote the formation of the blood-brain barrier are the
astrocytes
Selective attention is best defined as ______.
avoiding the distraction of irrelevant stimuli while seeking out and focusing on stimuli that are momentarily important
The synapse between neurons A and B is categorized as an ______.
axo-axonic synapse
Spinal nerves exiting between vertebrae of the spinal column contain ______.
axons of both afferent and efferent neurons
Neurons involved in the control of voluntary movements are located in cellular clusters deep within the cerebral hemispheres called the ______. Multiple choice question.
basal nuclei
During selective attention, the EEG pattern that would predominate is the pattern
beta
In skeletal muscle fibers, ATP ______.
binding to myosin ATPase induces conformational changes that break the actin and myosin bond is used by myosin ATPase to energize the myosin cross bridge is used for calcium transport back to the sarcoplasmic reticulum
Which type of taste receptor responds to substances such as arsenic and plant alkaloids like strychnine?
bitter
The exchange of substances between blood and the extracellular fluid in the CNS is different from the exchange between blood and the extracellular fluid of other tissues; it is more restrictive in the CNS due to the ______.
blood-brain barrier
In smooth muscle cells, the source of cytosolic Ca2+ that activates contraction is ______.
both the sarcoplasmic reticulum and extracellular Ca2+ entering through plasma membrane Ca2+ channels
An individual who has a flat EEG, and displays only spinal reflex responses to pain is said to be ______.
brain dead
The monoamines norepinephrine, serotonin, and histamine are are released from neurons of the reticular activating system that originate in the ______.
brainstem
The cyclic changes in states of consciousness that individuals undergo each day involve neurons of nuclei in the ______. Multiple choice question.
brainstem and hypothalamus
Olfactory nerves synapse onto the olfactory
bulbs
In smooth muscle, calcium combines with the protein which activates a kinase that phosphorylates the myosin light chains.
calmodulin or CaM
In the activation mechanism of smooth muscle, Ca2+ binds with ______ and causes the activation of ______ which then phosphorylates myosin and activates contraction.
calmodulin; myosin light-chain kinase
Transient receptor potential (TRP) proteins can be stimulated by the chemical ligand called , found in chili peppers, and perceived as being hot.
capsaicin
The ______ is like the cerebrum in that it consists of paired hemispheres with an outer layer of cortical cells and several deeper cell clusters. It does not initiate motor movements, but is an important center for coordinating movements and for coordinating posture and balance.
cerebellum
A synapse that transmits information via the release of neurotransmitters into the synaptic cleft between cells is termed a(n)
chemical synaspe
The sensory receptors responsible for the senses of taste and smell are ______. Multiple choice question.
chemoreceptors
If a neuron releases the neurotransmitter acetylcholine, it is referred to as a(n) ______ neuron. Multiple choice question.
cholinergic
Protruding into each brain ventricle is a structure called a , BLANK BLANK composed of simple cuboidal to simple columnar epithelium, that forms cerebrospinal fluid from blood in the capillaries with which each is associated.
choroid Blank 2: plexus
The structures that form an interface between the bloodstream and each ventricle of the brain that are responsible for the formation of cerebrospinal fluid are called the ______.
choroid plexuses
Match the arousal state with its definition.
coma- pt cannot be aroused, but may have some level of consciousness brain dead- no nervous system function above the spinal cord persistent vegatative state- pt unaware of surroundings but has sleep/wake cycle
The contributions of Na+, K+ and Cl- to the overall membrane potential are mainly a function of their ______. Multiple choice question.
concentration gradients and relative permeabilities
The function of interneurons is to
connect neurons within the CNS
A big dog barks unexpectedly at Ellen and she feels scared. Her feeling of being scared is an example of a ______.
conscious experience
When the force-generating mechanism of a muscle is activated, it is called a(n)
contraction
Three basic types of skeletal muscle fiber types can be distinguished on the basis of their ______. Multiple choice question.
contraction velocity and metabolic production of ATP
Shanice was in a traumatic accident and was given morphine for her pain. She begins to require higher dosages of morphine to manage her pain, so her doctor switches her to another opioid pain killer. Shanice is less responsive to the effects of the second opioid drug than might be expected, however, due to an effect called ______. Multiple choice question.
cross-tolerance
The electrical potential difference between two areas tends to make the charges flow, thus producing a ______. Multiple choice question.
current
The movement of electrical charge is called a(n)
current
The progressive change in the size of a skeletal muscle caused by destruction of motor neurons that activate it is called
denervation atrophy
If the neurons that carry information to a skeletal muscle are destroyed, the result is ______.
denervation atrophy
A subthreshold stimulus to a neuron ______.
depolarizes the local membrane potential briefly before it returns to the resting potential does not generate an action potential
The pituitary gland is part of the ______. Multiple choice question.
diencephalon
In order for taste buds to respond to a chemical, that chemical must be ______.
dissolved in liquid
The primary neurotransmitter which mediates the brain reward system is
dopamine
Sensory fibers of a spinal nerve are found in the (dorsal or ventral?) root, and motor fibers are found in the (dorsal or ventral?) root.
dorsal, ventral
Threshold stimuli ______.
elevate the membrane potential sufficiently to generate an action potential
The vestibular apparatus is a series of tubes filled with ______ that functions to detect ______.
endolymph; head motion
The ability of cells with voltage-gated ion channels to produce electrical signals is called ______.
excitability
When a region of brain cells die and excessive glutamate is released, it can over-activate NMDA receptors of nearby cells, causing them to die also, in a spreading wave of damage. This phenomenon is called ______. Multiple choice question.
excitotoxicity
A temporary decline in muscle tension resulting from previous contractile activity is known as ______. Multiple choice question.
fatigue
You will feel hungry if you have increased blood concentrations of the hormone
ghrelin
During the first 5 to 10 minutes of moderate intensity exercise, the fuel used by skeletal muscle fibers to produce ATP by oxidative phosphorylation is mainly ______.
glucose from muscle glycogen
Excitotoxicity is a phenomenon in which regions of damage in brain tissue tend to spread due to excess release of the neurotransmitter _______.
glutamate
The most common excitatory amino acid neurotransmitter in the central nervous system is
glutamate
The primary neurotransmitter at an estimated 50% of excitatory synapses in the CNS is ______. Multiple choice question.
glutamate
If prolonged exercise intensity exceeds about 70% of the maximum rate of ATP breakdown, ______ contributes an increasingly significant fraction of the total ATP generated within skeletal muscle. Multiple choice question.
glycolysis
A(n) potential is decremental; that is the flow of the charge decreases as the distance from the site of origin increases. This is unlike what happens in a(n) potential, where the signal is regenerated in each section of the axon membrane.
graded action
Receptor potentials that occur in sensory neurons are examples of
graded potentials
The BLANK (white or gray?) matter of the CNS is composed of high concentrations of cell bodies and dendrites.
gray
The sense of taste is known as
gustation
The cerebral cortex is organized into sinuous ridges called ______ separated by deep grooves, called ______.
gyri; sulci
Click on three of the following structures that are important interconnected structures that are part of the limbic system. Multiple select question.
hippocampus thalamus hypothalamus
Sour taste is created when BLANK ions block K+ channels in the receptor's plasma membrane.
hydrogen
The involuntary tetanic contraction of skeletal muscles that occurs when the extracellular Ca2+ concentration decreases to around 40% of its normal value is referred to as
hypocalcemic Blank 2: tetany
The portion of the diencephalon responsible for homeostatic regulation of the internal environment and for behaviors having to do with preservation of the individual (such as eating, drinking, and so on), is called the ______.
hypothalamus
The region of the brain below the thalamus, which is also the master command center for nervous and endocrine system coordination, is called the
hypothalamus
After damage to the dominant hemisphere, the opposite hemisphere can acquire some language function ______.
in children-Language plasticity is generally greatly diminished after puberty.
Ganglia in sympathetic autonomic pathways are found ______; parasympathetic pathway ganglia are found ______.
in two chains close to the spinal column; within or close to target organs
Receptors found in postsynaptic densities of synapses that both bind to neurotransmitters and act as ion channels are known as ______.
ionotropic receptors
An action potential ______.
is an all-or-none event is conducted without decrement occurs very rapidly
The resting membrane potential of body cells ______.
is negative, with values varying from -5 to -100 mV
The optimal muscle length (Lo) in skeletal muscle fibers ______.
is the length where the most actin and myosin interactions can take place and the most force is generated is close to the normal resting length of muscle due to tendon insertion points
Creatine phosphate ______. Multiple choice question.
is used to convert ADP into ATP
In most people, the cerebral hemisphere that is specialized to handle specific tasks involving producing and comprehending language is the BLANK hemisphere.
left
A prolonged fast results in decreased amounts of the appetite-suppressing hormone
leptin
An external force on a muscle is known as the ______.
load
The force exerted on a muscle by an object is the , whereas the force exerted on an object by a contracting muscle is known as muscle .
load tension
The specific nerve fibers which send the signal to the brain determines signal _____.
location
Neurons radiating to various areas of the brain from the ______ release norepinephrine, which acts as a neuromodulator to enhance signals transmitted by certain sensory inputs, and so is important for selective attention. Multiple choice question.
locus ceruleus
The ability to recall the name of someone you met a week ago at a party is an example of ______
long-term memory
This figure demonstrates ______.
long-term potentiation
If the electrical resistance is high, the current flow will be ______. Multiple choice question.
low
Chemical synapses ______.
may contain more than one transmitter at a time use neurotransmitters released by the presynaptic cell to transmit signals to the postsynaptic cell have a synaptic cleft between pre- and postsynaptic cells
The equilibrium potential of an ion is the ______.
membrane potential at which ion flux due to the membrane potential is equal and opposite to the flux due to the concentration gradient
The physiological process that changes an experience into the memory of that experience is called ______.
memory encoding
Neurotransmitter receptors that act indirectly on separate ion channels through a G protein and/or a second messenger are referred to as ______. Multiple choice question.
metabotropic receptors
The type of stimulus, such as whether it is heat, cold, sound or pressure, is known as the stimulus
modality
Orexins stimulate the release of ______ by neurons of the reticular activating system.
monoamines
A prolonged inner emotion that most people feel they have control over is known as a(n)
mood
Which is most responsible for the absolute refractory period of a neuron? Multiple choice question.
Voltage-gated Na+ channels open and then inactivate.
People who speak rapidly and fluidly, yet incomprehensibly, producing scrambled speech, have experienced damage to BLANK area of the brain.
Wernicke's area
With reference to the load-velocity relationship in skeletal muscle fibers, under what conditions will the velocity of shortening be the greatest? Multiple choice question.
When the load on the fiber is zero
The dark lines that can be seen in the middle of each I band and which mark the ends of a sarcomere are known as the
Z lines,
The ______ define the limits of a sarcomere.
Z lines
A motor neuron and all the muscle fibers that it innervates is called a(n)
motor unit
Based on electrical characteristics of their plasma membranes, smooth muscles can be divided into general groups, unit smooth muscles and unit smooth muscles.
multi or multiunit Blank 2: single
Sensory receptors located in skeletal muscles that contribute to posture and movement by indicating muscle length are called stretch BLANK receptors
muscle Blank 2: spindles or spindle
A genetic disease caused by the absence or defect of one or more proteins that make up the costameres in striated muscle is
muscular Blank 2: dystrophy
Within each skeletal muscle fiber densely packed, striated subunits known as extend in parallel rows from one end of the cell to the other leaving little room between for other organelles. The striations in these elongated structures are caused by the regular arrangement of thick and thin filaments into sarcomeres.
myofibrils
The closing of voltage-gated K+ channels during repolarization of an action potential is an example of ______ feedback; the opening of Na+ channels during the depolarizing phase of an action potential is an example of ______ feedback.
negative; positive
A collection of afferent and efferent neuron axons wrapped together with connective tissue in the peripheral nervous system is called a ______.
nerve
A collection of axons encased in connective tissue in the peripheral nervous system is called a(n)
nerve
The sensation resulting from tissue damage or exposure to noxious stimuli is
nociception
Neurons originating in the locus ceruleus of the pons release the neurotransmitter ______, which acts as a neuromodulator to enhance signaling in specific areas of the brain and thus improves information processing for selective attention. Multiple choice question.
norepinephrine
Within the CNS, an aggregation of neuron cell bodies is called a(n)
nucleus
After spinning around in a swiveling chair for 20 seconds, a person is stopped and opens her eyes. Large, jerky back-and-forth movements of her eyes occur, a phenomenon called
nystagmus
The sense of smell is also known as
olfaction or olfactory
Most myofibrils extend from ______.
one end of the muscle fiber to the other end of the muscle fiber
The length at which skeletal muscle fibers develop the greatest isometric active tension is termed the
optimal or optimum Blank 2: length
The suprachiasmatic nucleus (SCN) regulates both sleeping and waking states. In the morning it stimulates the secretion of ______, and at night it stimulates the secretion of ______.
orexins; melatonin
By convention, when describing a cell's membrane potential the ______ of the cell is assigned a value of zero, and the voltage is defined as the positive or negative charge on the ______ of the cell. Multiple choice question.
outside; inside
During moderate intensity exercise, most of the ATP used for muscle contraction is formed by ______. Multiple choice question.
oxidative phosphorylation
Patients who have lost a body part by accident or amputation sometimes experience sensory perception in that part as though it were still present. This phenomenon is called
phantom Blank 2: limb or limbs
The general term that describes the ability to modify the connectivity and function of neural tissue is called
plasticity
A rounded bulge located between the midbrain and the medulla oblongata is the
pons
The efferent autonomic neurons that synapse onto effector cells such as smooth and cardiac muscle are referred to as BLANK neurons.
postganglionic
The permeability of a resting plasma membrane is greater for ______ than it is for ______; therefore, a net negative membrane potential develops.
potassium; sodium
A difference in the amount of electrical charge between two points in space is defined as a difference in electrical
potential or voltage
If neurotransmitter release from neuron A increases the amount of Ca2+ that enters neuron B during an action potential, ______ of the synapse between neuron B and C will occur.
presynaptic facilitation
In ______, the amount of an excitatory neurotransmitter released from an axon is decreased by the effects of another neuron synapsing near its axon terminal.
presynaptic inhibition
Behaviors that fulfill homeostatic needs are known as ______. Multiple choice question.
primary motivated behaviors
In afferent neurons, the initial depolarization to threshold that initiates action potentials is achieved by a graded potential called a(n)
receptor
In afferent neurons, the initial depolarization to threshold that initiates action potentials is achieved by a graded potential called a(n) potential.
receptor
When a receptor responds normally when first exposed to a neurotransmitter but then eventually fails to respond despite the continued presence of the neurotransmitter, this is known as
receptor Blank 2: desensitization
A graded change in membrane voltage occurring in sensory cells in response to a stimulus is called a ______. Multiple choice question.
receptor potential
When skeletal muscle contractions of greater strength are needed, additional motor units are activated in a process known as
recruitment
Nociceptors from internal organs often activate interneurons linked to the somatosensory cortex that represents a superficial body part. This is known as BLANK pain.
referred
The sensation of pain from a body part may actually indicate injury to a different body part. This "mix-up" of pain signals is a phenomenon known as pain.
referred
Acetylcholine (ACh) is ______.
released by neurons within the brain released onto skeletal muscle cells by motor neurons a neurotransmitter
Ions with charges of the same type ______ each other, while ions with opposite charges ______ each other.
repel; attract
Neural activity that corresponds to a conscious experience most likely ______.
resides in a set of neurons in various parts of the brain that are temporarily functioning together in a specific way
The hindrance to electrical charge movement is known as
resistance
All inactive cells in the body maintain a voltage difference across their membrane, called the in which the inside of the cell is negatively charged in comparison to the outside of the cell.
resting membrane potential
All cells under resting conditions have a voltage difference between the inside and outside of their plasma membranes, which is referred to as the ______.
resting membrane potential
Transitions between the awake state and sleeping state are regulated by the ______. Multiple choice question.
reticular activating system
The ______ runs throughout the core of the brainstem and consists of loosely arranged nuclei intermingled with bundles of axons. Its axons release biogenic amines that are critical in regulating sleep and wakefulness.
reticular formation
Fibers from the cerebellum connect directly or indirectly with the ______, ______, and the ______.
reticular formation. primary motor cortex. pons and spinal cord.
Two general concepts that are inseparable from motivation are ______.
reward and punishment
The term used to describe the type of action potential propagation that regenerates itself at nodes in a myelinated axon is conduction.
saltatory
The term used to describe the type of action potential propagation that regenerates itself at nodes in a myelinated axon is
saltatory conduction
The blue, web-like structure in the diagram is the
sarcoplasmic, S, reticulum, R,
Changes in rotational speed of the head are sensed by the
semicircular or vestibular Blank 2: canals or apparatus
If sensory information reaches consciousness, it can be called a ______.
sensation
Damage to cortical areas that results in a person ignoring parts of their body or their visual field produces the condition known as ______. Multiple choice question.
sensory neglect
The portions of afferent neurons farthest from the CNS have
sensory receptors, which respond to physical or chemical changes in their environment by generating electrical signals
Which of the following neurotransmitters are categorized as biogenic amines?
serotonin dopamine histamine norepinephrine
The memory category called ______ registers and retains incoming information for seconds to minutes, during a period that we consciously keep that information "in mind." Multiple choice question.
short-term memory
Variation in proportions of muscle fiber types determine whole muscle capabilities. For example, elite distance runners have a high proportion of ______ fibers in the gastrocnemius muscle of the leg, while elite sprinters have a high proportion of ______ fibers in the same muscle. Multiple choice question.
slow-oxidative; fast-glycolytic
The neurons of the ______ division of the nervous system innervate skeletal muscle, whereas the neurons of the ______ division of the nervous system innervate smooth and cardiac muscle, glands, neurons in the gastrointestinal tract, and other tissues.
somatic; autonomic
Because of evidence regarding the action of antidepressant medications such as their long latency, it is thought that they act by ______.
stimulating the growth of new neurons in the brain
Describing an action potential as "all-or-none" means that ______.
stimuli are either suprathreshold (action potential occurs) or subthreshold (no action potential); action potentials are not graded
The chemical or energy that results in the activation of a sensory receptor is known as a(n
stimulus
Which of the following are characteristics of skeletal muscle?
striated multinucleate
A stimulus that causes a graded depolarization that is too small to generate an action potential is called a(n) stimulus.
subthreshold
The main circadian pacemaker in the body resides in the .
suprachiasmatic Blank 2: nucleus
The anatomically specialized junction between two neurons where electrical and chemical activity in one neuron influences excitability of the other is called a(n)
synapse
The entire structure within the circle formed by these two adjacent neurons is called a
synapse
A synapse could be excitatory or inhibitory depending on ______.
the type of postsynaptic ion channel influenced by the signal transduction mechanism
In sensory physiology, the term "adequate stimulus" means ______.
the type of stimulus (modality) to which a particular receptor is most suited to respond
A stimulus that is just strong enough to trigger the voltage-gated channels of the initial segment of an axon to open and begin the action potential is called a(n)
threshold
John has been using heroin for a while. To feel the same effects these days, he needs to take much higher dosages; this effect is known as
tolerance
Afferent neurons convey information ______ the CNS, while efferent neurons convey information ______ the CNS.
toward; away from
The conversion of stimulus energies such as pressure, light, or chemical concentration into electrical signals is referred to as sensory
transduction
Electrical synapses ______.
transmit signals faster than chemical synapses conduct an action potential directly between cells via connecting gap junctions
Electrical synapses ______.
transmit signals faster than chemical synapses conduct an action potential directly between cells via connecting gap junctions Select a concept resource to continue.Read About the ConceptAssignment Resources Feedback Next QuestionReading
The protein inhibits contraction of skeletal muscle fibers by blocking cross-bridge binding sites on actin.When Ca2+ binds to the protein the binding sites are unblocked and cross-bridge cycling occurs.
tropomyosin troponin
A contraction known as a muscle occurs when a muscle fiber is stimulated with a single action potential.
twitch
Nociceptor fibers are small-diameter fibers and are typically ______.
unmyelinated
Chemical synapses ______.
use neurotransmitters released by the presynaptic cell to transmit signals to the postsynaptic cell have a synaptic cleft between pre- and postsynaptic cells may contain more than one transmitter at a time
The innervation of smooth muscle cells by autonomic neurons involves neurotransmitter release from swollen areas along postganglionic neurons known as
varicosity
The utricle, saccule and semicircular canals are collectively called the apparatus.
vestibular or labyrinth
Ion channels that are closed when the cell is at its resting potential but open when the cell's membrane potential changes are categorized as
voltage-gated
During the relative refractory period of an axon ______. Multiple choice question.
voltage-gated Na+ channels change from the inactivated state to the closed state
The units of electrical potential in biological systems are milli-
volts
Temporal summation within the nervous system occurs ______. Multiple choice question.
when successive signals arriving from a single presynaptic neuron generate postsynaptic potentials that summate with each other
The location of a stimulus is encoded mainly by _______.
which neurons deliver action potentials to the brain
Areas of the central nervous system that contain a high concentration of axons form the BLANK matter
white matter
When a person exhibits physical symptoms if they don't take a particular substance they are use to taking, it is known as ______
withdrawal
Which of these are characteristics of smooth muscle cells?
Often interconnected into sheets of cells Single nucleus Capacity for cell division throughout life Small and spindle shaped, diameter between 2 and 10 microns Need help? Review these concept resources. Feedback Next QuestionReading
Which cell type is NOT found within the olfactory epithelium? Multiple choice question.
Olfactory bulb cells
Where are the olfactory bulbs located? Multiple choice question.
On the undersurface of the frontal lobes.
An ambulance drives down the road with its siren blaring. Pooja momentarily stops what she is doing, turns her head to face the street and watches as it drives by. This is an example of what type of conscious experience? Multiple choice question.
Orienting response
Which of the following are causes of nystagmus?
Pathology of the vestibular apparatus or vestibulocochlear nerve. Persistent spinning of fluid in the semicircular canals after the head stops rotating. High blood alcohol concentrations.
Which of the following are layers of the meningeal membrane?
Pia mater Arachnoid mater Dura mater
What viral disease destroys motor neurons and eventually leads to skeletal muscle paralysis and death due to respiratory failure? Multiple choice question.
Poliomyelitis
Which are TRUE about the anatomy of efferent autonomic pathways of the autonomic nervous system?
Preganglionic neurons originating in the CNS synapse onto postganglionic neurons in a ganglion in the PNS. Postganglionic neurons originating in ganglia in the PNS synapse onto smooth muscle, cardiac and gland cells.
Antidepressant drugs typically influence the effects of which two neurotransmitters?
Serotonin Norepinephrine
What three main characteristics of a stimulus are encoded by sensory receptors?
Stimulus location Stimulus intensity Stimulus modality
Which two neurotransmitters are released by nociceptors? Multiple select question.
Substance P Glutamate
Which of the following best describes the mechanism of twitch summation in a single skeletal muscle fiber? Multiple choice question.
Successive activation occurs before the fiber has relaxed from a previous twitch, so the number of bound cross-bridges increases.
The repolarization phase of a neuronal action potential is produced primarily by the ______. Multiple choice question.
efflux of K+
Synapses that consist of gap junctions which allow the local currents from action potentials in one neuron to flow directly across the junction to another neuron are called BLANK synapses.
electrical
Long-term potentiation involves a(n) ______ in synaptic effectiveness.
increase
Orexin secretion by neurons of the hypothalamus is associated with ______ wakefulness and ______ appetite.
increased; increased
The membrane potential of a postsynaptic neuron is either driven farther from threshold (hyperpolarized) or stabilized at its resting potential at an ______. Multiple choice question.
inhibitory synapse
Feelings of joy, anxiety, and hope are examples of ______.
inner emotions
A cytokine thought to be a chemical regulator of the sleep state is ______. It also has important functions in immune defense, which might explain why sleepiness is often a symptom of illness.
interleukin-1
Neurons entirely within the CNS that form links between other neurons and comprise 99% of all neurons are called
interneurons
he basal nuclei are regions of the cerebrum containing neurons ______.
involved in the control of skeletal muscles
Which 3 of the following are true about action potential conduction in myelinated axons?
t is faster than in unmyelinated axons. It is called called saltatory conduction. Propagation occurs without a decrease in action potential size.
A family of proteins called transient receptor potential (TRP) proteins are found in sensory neurons that sense ______.
temperature
The type of summation in which the high-frequency activity of a single presynaptic axon causes EPSPs in a postsynaptic neuron that summate at the initial segment of the axon is called BLANK summation. Listen to the complete question
temporal summation
The BLANK a brain region involved in selective attention. It is a synaptic relay station for the majority of ascending sensory pathways, acting as a filter for ascending sensory information ascending to the cerebral cortex
thalamus
In most people, the right cerebral hemisphere is the general location where ______ are processed.
the affective components of language
Preattentive processing is best defined as ______.
the evaluation of the importance of sensory stimuli that occur prior to focusing attention
Which of the following body parts has the most neurons associated with it in the primary somatosensory cortex of the brain?
the face
Limitations on the maximum action potential firing frequency of neurons are determined by ______. Multiple choice question.
the length of the refractory periods
