A&P 10-12
A small amount of muscle tension and muscle definition (the appearance of muscle beneath the skin) is present even in a relaxed muscle. A person who is physically fit due to regular exercise, will have more of this characteristic of muscle tissue than someone who is not fit. What is this characteristic?
Muscle tone
Pores are membrane transport proteins that are always open. T/F
TRUE
The cytosol and extracellular fluid both maintain a neutral voltage. T/F
TRUE
The larger the diameter of an axon, the faster the conduction of an action potential. T/F
TRUE
The myosin head setaches from the actin filament after new ATP binds to myosin T/F
TRUE
Warm up exercise before stretching or strenuous muscle activity prevents injury because tissues stretch best when gentle force is applied at elevated temperatures. T/F
TRUE
autonomic motor neurons regulate:
smooth and cardiac muscle
list the muscles of the quadriceps group
rectus femoris, vastus lateralis, vastus medialis, vastus intermedius
What is the cell membrane of a muscle fiber called?
sarcolemma
what part of the rotator cuff is the most frequently injured and why
supraspinatus becuase of its location between the head of the humerus and the acromion of the scapula, this tendon is compressed during should movements
what are the rotator cuff muscles
suprspinatus, subscapularis, teres minor, infraspinatus
sEMG stands for
surface electromyogram
What results in the depolarization of the cell membrane? -Mechanically-gated channels open to allow potassium ions to diffuse into the cell causing the membrane to become more negatively charged inside. -Chemically-gated potassium channels open allowing potassium ions to diffuse out of the cell causing the inside of the membrane to become more negative. -Voltage-gated potassium channels open allowing potassium ions to diffuse out of the cell taking their positive charges with them. -Voltage-gated sodium channels open allowing sodium ions to enter the cell to cancel negative charges on the inside of the membrane.
-Voltage-gated sodium channels open allowing sodium ions to enter the cell to cancel negative charges on the inside of the membrane.
What are the three FUNCTIONAL classifications of neurons?
-sensory/afferent neurons -motor neurons/efferent neurons -inter/association neurons
In a hiatus hernia, the stomach protrudes through which opening of the diaphragm? the caval opening the esophageal hiatus the mediastinum the aortic hiatus the inguinal hiatus
the esophageal hiatus
Muscles act on bones to produce movement. The bones act as levers and the joints act as __________.
the fulcrum
The intrinsic muscles of the foot have their origins and their insertions within the foot. True False
true
If the accumulation of graded potentials in the trigger zone reaches threshold, the result is
voltage-gated channels open.
What is the equilibrium potential of Na+ (sodium's happy place)? Why is this important?
+40mV, important because sodium will want to move either in or out of the cell, if a channels open, depending on where it can meet its equilibrium potential, makes the muscle cell more positive to open voltage gated sodium channels
The resting membrane potential is about _____mV. -55 to 0 -55 to -70 -70 to -90 0 to +30
-55 to -70
What is the RMP for neurons?
-70mv
Which ion is required for exocytosis of ACh?
Ca2+
The term quadriceps refers to the shape of a muscle, and indicates this muscle is shaped approximately like a square, with four corners. True False
False
The supinator muscle extends the forearm at the elbow joint. True False
False; triceps brachii does dat
by what process foes the motor neuron stimulate the muscle cell?
Neurotransmitter(ACh- acetylcholine) is released into the synaptic cleft to cause an action potential in the muscle cell
thin filaments are _____ nm in diameter and _____ micrometers long and made mostly of the protein ______. thick filaments are _____nm in diameter and ___ micrometers long and made mostly of myosin
8, 1-2, actin; 16,1-2, myosin
Thin filaments are found in ________ bands and made of 3 proteins called_____________.
A & I bands; actin, troponin and tropomyosin
How are neurotransmitters removed from the synaptic cleft? -Diffusion -Enzymatic degradation -Uptake by cells -All of these choices
All of these choices
what is a oligodendrocyte
CNS cell that makes the myelin sheath, creates the insulation of a electrical signal
What is stored in the sarcoplasmic reticulum?
Ca2+
What is gray matter made of? Where is it found in the brain? In the spinal cord?
Cell bodies, outside of the brain and the inside of the spinal cord
The mastoid process of the temporal bone is an important insertion point for muscles of the neck that move the head.TrueFalse
True
The regeneration tube guides the growth of a new axon from the proximal area across the injured area to the distal area where it replaces the original axon. True False
True
When calcium binds to troponin/tropomyosin, what happens to actin's active sites (myosin binding sites)?
actins active sites become free after calcium binds to troponin, which then releases tropomyosin from the active site and muscle contraction occur
Which of the following is the strongest muscle of mastication? buccinator masseter temporalis medial pterygoid lateral pterygoid
masseter
somatic motor neurons regulate
skeletal muscle
The pectoralis major and _____________ are the prime movers of shoulder adduction.
coracobrachialis
Describe summation of graded potentials.
correlates with signal strength/summation of graded potential. it is the sum amount of graded potential, or ions leaving and entering the cell, affecting the RMP, if enough positive ions come into the cell it may cause an action potential to fire once threshold for the cell is reached
these muscle fibers contribute to activities such as walking and sprinting
fast oxidative glycolytic fibers
When all rotator cuff muscles are activated at the same time they act to hold the head of the humerus in the _______________.
glenoid cavity
The ___________ is a rim of fibrocartilage that slightly deepens the glenoid cavity.
glenoid labrum
which muscle laterally rotate the hip?
gluteus maximus
which muscles rotate hip medially?
gracii, gluteus minimus, gluteus medius
Define ganglion:
group of cell bodies within the PNS
what is the rotator cuff
group of tendons that provide the strength and stability needed by the ball and socket joint of the shoulder
thick filaments are found in what bands and zone
h-zone and A-band
Which type of neuron is more abundant?
inter/association neurons- inbetween sensory and motor neurons, they allow the integration of sensory information and the plan and initiate the execution of a response by motor neurons
This structure is unique to cardiac muscle cells, and allows individual cells to be firmly attached to each other (to provide mechanical strength during contraction), and also allow the action potential to spread rapidly through the cardiac muscle tissue, so that contractions are smooth and coordinated.
intercalated discs
What do motor neurons do?
is output. also called efferents, receives motor commands from the brain and sends the command, to maintain homeostasis, to either somatic or autonomic nervous system
The depolarization of one area of the cell membrane provides enough positive charge to cause neighboring voltage-gated channels to reach threshold allowing the action potential to spread across the membrane. T/F
T/F
Action potential frequency increases with increasing application of stimuli. T/F
TRUE
As a nerve impulse travels along the axon, a depolarization of the membrane is caused by influx sodium gated channels. T/F
TRUE
Electrical synapses must have connexons on their cell membranes. T/F
TRUE
IPSPs help to regulate the frequency of action potential creation. T/F
TRUE
In an action potential, the signal is capable of traveling over long distances without losing voltage. T/F
TRUE
In order for Acetylcholine to be returned to the presynaptic cell, it must be hydrolyzed into acetate and choline. T/F
TRUE
Large, graded potentials will typically generate an action potential. T/F
TRUE
Myelination is created due to the wrapping of axons by Schwann cells. T/F
TRUE
Nearly all muscles of the body develop from an early embryonic layer of cells called the mesoderm. T/F
TRUE
Neurotransmitters only stimulate an action potential in the post synapse. They can never inhibit the production of an action potential. T/F
TRUE
To delay the onset of muscle fatigue, not all the motor units in a muscle will contract at the same time. Some will remain relaxed while others are contracting. If the contraction continues, and greater force is needed, more motor units will be recruited. T/F
TRUE
as long as the calcium and ATP inside the cell are adequate than the contraction cycles will repeatedly occur T/F
TRUE
calcium binds with troponin-tropomyosin complex and allows myosin to access the actin filaments T/F
TRUE
calcium ions entering the motor neuron cell cause the release of acetylcholine T/F
TRUE
Mechanically-stimulated gated channels are found on sensory neurons or sensory receptor cells. T/F
True
Synapses allow for information to be filtered and integrated. T/F
True
The gluteus medius is a common site for intramuscular injections. True False
True
The lateral (fibular) compartment of the leg contains two muscles that plantar flex and evert the foot: the fibularis (peroneus) longus and the fibularis (peroneus) brevis. True False
True
The muscles of facial expression insert onto the skin, so when they contract, they move skin rather than a joint. True False
True
The quadriceps femoris muscle (made up of a group of four muscles) is the largest muscle of the body. True False
True
The suprahyoid muscles are involved with swallowing (deglutition), while the infrahyoid muscles return the hyoid to its pre-swallowing position, and also act on the thyroid cartilage (Adam's apple) of the larynx in the production of speech. True False
True
Hyperpolarization requires an increase in K+ inside the cell an increase in Na+ inside the cell a decrease of K+ inside the cell an increase in Na+ inside the cell
a decrease of K+ inside the cell
A single mechanical or chemical stimuli will create -a graded potential. -an action potential. -none of the above. -all of these.
a graded potential.
Thick filaments are found in _______ bands and made of proteins called ______________.
a&H bands, myosin
what are astrocytes
abdundant cells that help to make the blood brain barrier, CNS cell
the head of the femur articulates with the deeply cupped _____ of the hip
acetebulum
the neurotransmitter released by the motor neuron to cause muscle contraction is:
acetylcholine
List the six major neurotransmitters:
acetylcholine, dopamine, norepinephrine, serotonin, GABA, and glutamate.
A treatment for myasthenia gravis is pyridostigmine which stops ACh from being broken down. Which does pyridostigmine inhibit?
acetylcholinesterase (the enzyme that breaks down ACh so more ACh is available to bind with sarcolemma receptors to allows muscle contraction cycles)
A change in the electrical state of the cell membrane which causes a response in the next cell is known as a(n)
action potential.
When the threshold of voltage-gated channels is reached and voltage-gated channels open, the resulting change in membrane potential is known as a(n) induction mode. transition state. graded potential. action potential.
action potential.
An antagonist muscle or muscle group is the one that is __________
acts in opposition to the agonist muscle or muscle group
During the downswing, a right-handed batter's right shoulder ___________ as the left shoulder __________________.
adducts and extends; abducts and extends
Neurogenesis occurs in the embryonic brain. occurs in the hippocampus even during adulthood. is inhibited by neuroglial products in most areas of the CNS. is inhibited by the absence of fetal growth stimulating factors. all of these are correct.
all of these are correct.
The nervous system: -works with the endocrine system to maintain homeostasis. -communicates with the body via action potentials (nerve impulses). -is responsible for perceptions and behaviors. -initiates voluntary movements. -all of these are correct.
all of these are correct.: -works with the endocrine system to maintain homeostasis. -communicates with the body via action potentials (nerve impulses). -is responsible for perceptions and behaviors. -initiates voluntary movements
What is the function(s) of the nervous system? -detecting stimuli -processing information -sending a response to muscles or glands -all of these choices
all of these choices
describe action potential
all or nothing response. it is the rapidly occurring depolarization(positive mv) and repolarization(negative mv), occurs from opening, primarily sodium and potassium, ion channels
The principle that states that a stimulus either causes an action potential or does not cause an action potential is known as the
all-or-none principle.
Define action potential:
allow cells to communicate over short and long distances and allow us to produce specific movements in our somatic and autonomic tissues(other electrically excited tissues)
when the electrical impulse of the motor neuron reaches the synapse, the release of neurotransmitters caused by:
an increase in intracellular calcium when voltage-gated calcium channels open
What do integrative neurons do?
analyzes incoming information, stores some aspects and makes decisions regarding appropriate behaviors (realizing a cars coming and need to move)
A muscle that acts as a __________ stabilizes the origin of the prime mover so that the prime mover may act more efficiently.
antagonist abductor fixator synergist agonist answer: fixator
The __________ is an intracapsular ligament which crosses the interior of the joint.
anterior cruciate ligament
Which ligament strengthens the posterior part of the knee joint?
arcuate popliteal ligament
The dendrites of a neuron: -are the main receiving region of a neuron -secrete neurotransmitters -conduct impulses toward another neuron -do not carry potentials, only axons do
are the main receiving region of a neuron
How are action potentials generated?
can occur from a change of ion concentration within a cell, causing the resting membrane potential to shift up or down from the resting membrane potential, causing an electrical(action potential) current/signal to be genere
During an action potential, a second action potential will always be generated have a decreased amplitude have an increased amplitude can only be generated if refractory period is over
can only be generated if refractory period is over
The type of channel that only opens when neurotransmitter attaches to its associated receptor is known as a
chemically-gated channel.
the deltoids three points of origin
clavicle, acromion of the scapula, and spine of the scapula)
based on amplitude and frequency of sEMG's motor unit acceleration in biceps brachii is greatest during
concentric isotometric conctraction
during arm extension, the type of contraction thatd occur in the triceps brachii is:
concentric isotonic contraction
Synergist muscles act to ____________
contract and stabilize the intermediate joints to prevent unwanted movements at intermediate joints/aid the movement of the prime mover
Myofibrils are composed of three types of proteins:
contractile, structural and regulatory
What makes up the PNS?
cranial nerves, spinal nerves, enteric plexuses in small intestine, sensory receptors in skin
Which of these muscles has a major role in opening the mouth (depressing the mandible)? masseter temporalis medial pterygoid digastric omohyoid
digastric
Which of the following homeostatic functions involve both skeletal and smooth muscle in the reproductive system? ejection of semen regulation of menstrual blood flow from the uterus movement of oocyte along the uterine tube orgasm during intercourse
ejection of semen
action of masseter
elavates mandible (jaw closure)
Improper lifting of a heavy load (such as trying to lift a box of books from its position on the floor), is most likely to cause painful back spasms in which muscle(s)? splenius capitis splenius cervicis longissimus thoracis erector spinae scalene
erector spinae
The __________ muscle(s) is (are) the primary extensor muscle(s) of the vertebral column. transversospinales erector spinae spinalis thoracis scalene group rotators
erector spinae
At the neuromuscular junction, the neurotransmitter acetylcholine is -inhibitory. -excitatory. -either excitatory or inhibitory, depending on the skeletal muscle -neither excitatory nor inhibitory
excitatory
Skeletal Muscles _______ on _________ to move the body.
exert force; tendons
the left knee is __________ during a right handed batters swing
extended
The quadriceps femoris is a knee __________ used to rise from a seated position.
extensor
What is the treatment for this disorder?
faciotomy- muscle fascia(connects muscle to bone) is cut to relieve pressure around the constricted compartments, allowing blood flow and increase blood supply
What type of skeletal muscle fiber would an Olympic quality weight lifter specifically be developing during training, to enhance his or her weight lifting power?
fast glycolytic fibers
action of rectus abdominus
flexes vertebral column, compresses abdomen
which originates on the pubis and inserts on the medial part of the tibia?
graciis; rotates hip medially
Which muscles are anterior that flexes the knee?
gracillis and sartorius
Define nucleus:
group of cell bodies within the CNS
The quadriceps femoris in the anterior compartment of the thigh is antagonized by the ___________ in the posterior compartment of the thigh.
hamstring muscles
in contrast to the shoulder joint, the hip joint:
has a more limited range due to a greater degree of bony interlocking
The lateral and medial tibiofemoral joints are modified _________ joints that permit flexion and extension.
hinge
What is the function of troponin?
holds down tropomyosin when it covers the myosin-binding sites on actin. also, when calcium binds to troponin, it goes through a change in shape(conformational change); causes tropomyosin to move from myosin binding sites on actin and muscle contraction begins as myosin binds to actin
prime move of the hip flexion is____
iliopsoas
The rectus femoris originates on the _________.
ilium
Where does summation take place?
in the soma, after stimulus is detected by dentrites
As one ages, the presence of slow oxidative fibers ___.
increases
concentric isotonic contraction
involves muscle shortening
What do sensory neurons do?
is input. also called afferents, arrive in the brain(central control) with information from the peripheral nervous system, sensory and somatic (propreception) information
hamstring muscles all originate at the _____ & insert on the tibia:
ischial tuberosity
When oxygen is plentiful inside a skeletal muscle cell, what happens to the pyruvic acid that is formed during glycolysis?
it diffuses into mitochondria to be broken down to generate ATP
What is the threshold voltage at the motor end plate? How do we reach threshold?
it is -65mV. after an action potential fires into a neuron at a neruomuscular junction, calcium flows into the neuron and binds to its vesicles which then exocytose its neurotransmitter, ACh(acetacholine) into the neuromuscular junction and binds to its receptors, the ligand gate sodium channel, which then open up, letting sodium in and causes the membrane potential to rise to -65mV which is threshold, then the voltage gated sodium channel open up to allow the rest of process of muscle contraction to occur
what happens to the neurotransmitter once an action potential is propagated on the muscle sarcolemma?
its immeadiately broken down by an eznyme called acetylcholinesterase
The teres major and __________ act synergistically to extend the shoulder.
latissimus dorsi
Resting membrane potential is maintained by -leak channels and sodium-Potassium pumps. -chemically-gated channels. -leak channels. -`sodium-Potassium pumps.
leak channels and sodium-Potassium pumps.
Consider the cell body of a neuron. Through which types of ion channel might sodium enter the cell body? Check all that apply! -ligand-gated channels -voltage gated channels -Na+1/K+1 ATPase -leakage channels
leakage channels,and ligand gated channels
isometric contraction
length of a muscle remains fixed while the muscle is developing tension
eccentric isotonic contraction
lengthening of muscle when muscle tension resists an action
The resting potential is maintained by the presence of many efflux K+ pores the Na+/K+ pump an ATP-driven pump moving K+ into the cell all of these
many efflux K+ pores the Na+/K+ pump an ATP-driven pump moving K+ into the cell all of these
the primary movement at the hips during a baseball batters swing it
medial rotation
The differences in electrical charges on either side of the cell membrane results in what is referred to as
membrane potential.
Patch clamp equipment in constant current mode allows researchers to measure -membrane thickness -neuron diameter -membrane potentials -neuron length
membrane potentials
The arrangement of fascicles can affect these two things:
muscle power and range of motion
Which situation will see the fastest conduction rate across an axon? -unmyelinated axon in with a thin axon diameter -myelinated axon -myelinated axon in with a wide axon diameter -unmyelinated axon
myelinated axon in with a wide axon diameter
What is white matter made of? Where is it found in the brain? In the spinal cord?
myelinated axons, central subcortical regions of the brain, outer regions of the spinal cord
neurons come from
neuro stem cells in the hippocampus
List the differences between neurons and glial cells:
neurons: -electrically excitable, cellular structures, cannot multiply and divide. 3 different kinds Glial: not electrically excitable, can multiply and divide, far more in number than neurons, 6 different kinds
what are the channels called that acetycholine opens at the neuromuscluar junction
nicotinic acetylcholine channels
The middle finger is the only finger that cannot be moved laterally by palmar interossei dorsal interossei lumbricals abductor digiti minimi
palmar interossei
which muscle adducts and flexes the hip?
pectineus, adductor magnus, adductor brevis, and adductor longus
Muscle fascicles can be arranged in one of several patterns. Which of the following patterns is not an example of the arrangement of fascicles in a muscle?
pennate elliptical fusiform triangular circular answer is elliptical
Muscles of the ____ assist in urination, defecation, erection of the penis or clitoris, and ejaculation. thorax abdomen perineum vertebral column none of these choices
perineum
The deep anterior forearm muscles insert on the __________. phalanges radius metacarpals ulna
phalanges
sarcolemma
plasma membrane of a muscle fiber; superior to the multiple nuclei of a muscle fiber
Which of the following ions pass through the resting neuronal cell membrane most easily? -sodium -calcium -potassium -phosphate
potassium
What ion sets the RMP? Why?
potassium because of its electrochemical gradient
At a synapse, the neuron sending the signal towards the synapse is called the _______ neuron. -presynaptic -postsynaptic -axodendritic -axoaxonic
presynaptic
the muscle cells contracting unit is known as the
sarcomere
in a muscle cell, calcium ions are stored in the
sarcoplasmic reticulum
Smooth muscle fibers do not have striations like skeletal and cardiac muscle cells do. This is because:
smooth muscles contain, thin, thick, and intermediate filaments but dont have organized sarcomeres like skeletal and cardiac muscle tissue, so smooth muscles doesnt striate
Depending on how specialized a type of muscle tissue is, the muscle fibers or cells of that tissue will have varied abilities to regenerate (healing and production of new cells). What type of muscle tissue has the greatest ability to regenerate?
smooth muscles have the best ability to regenerate, cardiac muscles can regenerate and skeletal muscles have very limited regeneration abilities
The depolarization phase of the action potential is due to diffusion of -potassium ions into the cell -potassium ions out of the cell -sodium ions out of the cell -sodium ions into the cell
sodium ions into the cell
Compartment syndrome occurs when:
some kinda fuggin external or internal pressure constricts the structures within a compartment, causing damaged blood vessels and reduces blood supply to the affect structures within the compartments.
action of trapezius
stabilizes, elevates, retracts and rotates scapula
A muscle's origin is where it attaches to the ___________ bone
stationary
Which rotator cuff muscle originates on the subscapular fossa of the scapula and inserts on the lesser tubercle of the humerus?
subscapularis
list the rotator cuff muscles
subscapularis, supraspinatus, infraspinatus, teres minor
The junction between a stimulating neuron and the next neuron or muscle fiber is known as a(n) -synapse. -initiating junction. -sensorium. -sequence regulator.
synapse.
The RMP is a difference in ________ across the cell membrane.
voltage
why are injections often given in muscles rather than subcutaneously
when prompt absorption is desired, when larger does than can be given subcutaneously are indicated, or when the drug is too irritating to give subcutaneously
What are the ways neurotransmitters can be cleared from the synapse?
diffusion, reuptake and degradation
Movement of ions through an open channel is due to
diffusion.
Typically graded potentials occur in the... -axon -dendrites and cell body -myelin sheath -axon terminal
-dendrites and cell body
Myelinated axons are capable of saltatory conduction. This allows for more rapid action potential conduction because -repolarization occurs only at the Nodes of Ranvier. -depolarization occurs across the entire membrane. -repolarization occurs across the entire membrane. -depolarization occurs only at the Nodes of Ranvier.
-depolarization occurs only at the Nodes of Ranvier.
As Ca++ ions enter the presynaptic membrane _____ of neurotransmitters occurs. -exocytosis -endocytosis -degradation -synthesis
-exocytosis
A single graded potential can produce an action potential. T/F
False
What is threshold for neurons?
-55mv
Why did the amplitude of the action potential did not increase as stimulation voltage increased above threshold? -Action potential is all or none. All voltage-gated Na+ channels open when threshold voltage is reached -The method used prevented changes from being observed -Refractory period prevented an increase in stimulation voltage -Potassium channels did not open
-Action potential is all or none. All voltage-gated Na+ channels open when threshold voltage is reached
Summation may lead to which of the following? -Hyperpolarization without action potential. -Depolarization without action potential. -Depolarization beyond threshold leading to action potential. -All of these.
-All of these.: -Hyperpolarization without action potential. -Depolarization without action potential. -Depolarization beyond threshold leading to action potential.
Choose the statement below that accurately represents a significant feature of graded potentials.: -Like graded potentials will subtract from each other to create a smaller graded potential. -Graded potentials activate enzymes to excite the cell. -Graded potentials randomly occur all the time but are of no significance. -Like graded potentials can sum to create a larger graded potential.
-Like graded potentials can sum to create a larger graded potential.
IPSPs are caused by all of the following except. -Cl- channels -K+ channels -Na+ channels -all of these
-Na+ channels
Electrical signals produced by neurons are known as -action potentials. -inducting pulses. -hyperpolarizing signals. -neuro-initiators.
-action potentials.
Sensory impulses are carried to the central nervous system by: -afferent neurons -efferent neurons -motor neurons -interneurons
-afferent neurons
List the names, locations (CNS or PNS), and function of the 6 types of glial cells:
-astrocyte: abundant and star shaped, makes blood brain barrier, in the brain, regulate what comes into brain -oligodendrocyte: makes myelin sheath formed around neuron axons all throughout CNS -ependymal cell: makes the cerebral spinal fluid that fills cavities in brain and surrounds and cushions both the spinal cord and brain -microglia: immune cell of the brain, monitor for infection/inflammation and activate when damage to the CNS occurs and phagocytose things when needed -schwann(neurolemocyte): myelin sheaths for axons in the PNS. just like oligodendrocyte but in the PNS -satellite: located in PNS, are insulators for neuron cell bodies and keep chemical homeostasis for cell body
What is the difference between the four types of channels and leak channels?
-leak channels allow passage of ions cause of electrochemical gradient, where it needs to be in an environment with its desired voltage and where the concentration of its element is low (primarily potassium). located in almost all cells, dendrites, cell bodies, and axons of all types of neurons -ligand gated channel: respond to chemical stimuli i.e. sodium comes to open up sodium ligand gated channels. located in dendrites and cell bodies of interneurons and motor neurons, and some sensory neurons -mechanical gated channels: respond to physical/mechanical stimulation such as pressure, vibration, movement, physical manipulation. located in sensory nuerons; touch, pressuer, pain receptors -voltage gated channels: respond to changes in membrane voltage, located in all axons of neurons
Multiple sclerosis involves a progressive destruction of the neuron's ___. -myelin sheath -axon -dendrites -cell body
-myelin sheath
The resting potential has the following characteristics: -positive inside and negative outside. -negative inside and positive outside. -move more sodium inside and more potassium outside. -none of these.
-negative inside and positive outside.
The depolarization phase of the action potential is due to the -opening of voltage-gated potassium channels -closing of voltage-gated sodium channels -opening of voltage-gated sodium channels -closing of voltage-gated potassium channels
-opening of voltage-gated sodium channels
Which statement is NOT true about electrical synapses? -they occur when there is direct contact between electrically excitable cells. -they allow rapid communication between cells. -they allow synchronization of cellular activities. -they are found in heart muscle -they allow the movement of ion through desmosomes
-they allow the movement of ion through desmosomes
Action potentials are generated at the -dendrite -neuron cell body -trigger zone -all of the answers are correct
-trigger zone (axon hillock)
Which of the following is not one of the quadriceps femoris group of muscles?1. gracilis2. sartorius3. vastus medialis4. vastus lateralis 1 only 2 only 3 only 4 only 1 and 2
1 and 2
Which of the following muscles act(s) to increase the size of the thoracic cavity during inhalation?1. diaphragm2. external intercostals3. internal intercostals 1 only 2 only 3 only 1, 2 & 3 1 and 2
1 and 2
Which of the following muscles have an insertion on the xiphoid process?1. rectus abdominis2. internal and external obliques3. transversus abdominis 1 only 2 only 3 only 1 and 3 2 and 3
1 and 3
Describe what is happening at the four key points during an action potential. What channels are open and what channels are closed at each point? What is happening to the RMP at each point?
1st: resting membrane potential, ion channels are closed 2nd: stimulus causes depolarization to threshold 3rd: voltage gated Na+ channels open(reaching threshold and firing action potential) after reaching threshold, Na+ flows out channels that inactivate and K+ channels are still open and flows Na+ out of cell, causing RMP to become more negative than -70 4th: repolarization, sodium/potassium pumps corrects ion concentration to meet and maintain RMP. volatge gated K+ channels still open and Na+ channels are in the resting state
Which of the following muscles act to stabilize the scapula, and would also, when contracted, pull the shoulders back (like a soldier at attention)?1. trapezius2. levator scapulae3. rhomboid major and minor 1 only 2 only 3 only 1 & 2 2 & 4
3 only
What is a sarcomere?
A sarcomere is the functional unit of striated muscle. This means it is the most basic unit that makes up our skeletal muscle. Narrow, plate‐shaped regions of dense protein material called Z discs separate one sarcomere from the next. Thus, a sarcomere extends from one Z disc to the next Z disc.
What are the components of a triad?
A transverse tubule and the two terminal cisterns
the sarcomere consists of all of the following except:
A) Actin B) Troponin C) Myosin D) The motor Neuron Answer is D
which would be the first step of a contraction cycle?
ATP is hydrolyzed by the myosin head
How do we stop a muscle contraction? What molecule and ion are needed to do this?
ATP is the molecule needed and causes myosin to let go of actin and resets tropomyosin's rope on top of actin and troponin holds down the rope, after calcium(the. ion needed) is removed from the sarcomere and transported back to sarcoplasmic reticulum
If I can block neurotransmitters attaching to chemically-gated sodium channels, what will be the result? -The cell will become hyperactive -An action potential will not be produced -The cell will die -The cell will depolarize but not repolarize
An action potential will not be produced
Which of the following does not affect the conduction rate across an axon? -Distance from the stimulus -Diameter -Temperature -Myelination
Distance from the stimulus
Which list includes muscles that are responsible for facial expressions? A) deltoid, pectoralis major, serratus anterior B) rectus abdominis, internal oblique, transversus abdominis C) serratus anterior, external intercostals, internal intercostals D) levator scapulae, rhomboid minor, subscapularis E) zygomaticus major, risorius, platysmaterm-164
E) zygomaticus major, risorius, platysma
EPSP and IPSP are the two types of electric charges found on the membrane of the postsynaptic nerve at the synapse. The EPSP is caused by the flow of positively-charged ions into the postsynaptic nerve whereas, the IPSP is caused by the flow of negatively-charged ions into the postsynaptic nerve.
EPSP and IPSP are the two types of electric charges found on the membrane of the postsynaptic nerve at the synapse. The EPSP is caused by the flow of positively-charged ions into the postsynaptic nerve whereas, the IPSP is caused by the flow of negatively-charged ions into the postsynaptic nerve.
Chemical synapses allow for two-way movement of signals. T/F
FALSE
Cooling an axon will increase the speed of an action potential. T/F
FALSE
EPSPs are caused by a hyperpolarization of the post-synaptic membrane. T/F
FALSE
Rabies virus and tetanus toxin use retrograde transport to travel backward along axons to reach the neuronal cell body. Retrograde transport is a type of slow axonal transport. TrueFalse
FALSE
The effect of neurotransmitters on the post synapse is long lasting. T/F
FALSE
The resting potential maintained by the Na+/K+ pump creates a slightly positive charge on the inside of the cell membrane. T/F
FALSE
Gray matter has its distinctive color due to myelination of axons. True False
FALSE, it is white matter that has its distinct color from myelinated axons, and gray matter has unmyelinated axons, cell bodies, neuroglia, dendrites and axons terminals of axons
Stretching is most effective at reducing injury and promoting greater flexibility if it is done over the course of many weeks, and always when the muscle is cold (before beginning to exercise). T/F
FALSE; stretching cold muscles doesnt increase flexibility. Tissues stretch best when slow, gentle force is applied at elevated tissue temperatures
During repolarization, more sodium ions are brought into the cell to reset the membrane potential. T/F
FAlse
In a graded potential, the voltage does not diminish with the distance. T/F
False
Ions, at any time, can pass freely through the cell membrane from one side to the other. T/F
False
The diaphragm, a muscle involved with breathing, is innervated by the phrenic nerve, a major nerve of the thoracic spinal nerves. True False
False
How does a neurotransmitter signal the post-synaptic cell to respond? -It binds to receptors on the post synaptic cell membrane. -It creates an electromagnetic signal that is transmitted to receptors inside the post synaptic cell. -It inhibits the continual flow of hydrogen ions into the post synaptic cell to change its pH. -It activates an enzyme which allows the action potential to flow directly from the presynaptic cell to the post synaptic cell.
It binds to receptors on the post synaptic cell membrane.
A resting nerve fiber is polarized because the concentration of -Na+ and K+ ions is higher on the inside of the cell membrane -Na+ and K+ ions is higher outside the cell membrane -Na+ is higher on the inside and K+ is higher on the outside -Na+ is higher on the outside and K+ is higher on the inside
Na+ is higher on the outside and K+ is higher on the inside
Which of the following is not a benefit of an electrical synapse? -One-way movement of signals. -Better coordination between cells. -Two-way movement of signals. -Quicker movement of signals.
One-way movement of signals.
The autonomic nervous system is part of the -PNS -SNS -CNS -All of these choices
PNS
Which branch has the capacity for regeneration?
PNS (peripheral nervous system)
Once neurotransmitters are released, they do not remain in the synapse. What happens to them? -Some are degraded by enzymes while some are transported back into the presynaptic cell. -Some decompose on their own by a process known as autodecomposition. -Some are degraded by enzymes. -Some are transported back into the presynaptic cell.
Some are degraded by enzymes while some are transported back into the presynaptic cell.
Graded potentials: -arise when ion movement causes a minor change in the resting membrane potential. -usually propagate down the length of an axon. -occur when voltage-gated channels open. -are most often observed in axons. -are usually associated with ion movement through leakage channels.
arise when ion movement causes a minor change in the resting membrane potential.
Muscle paralysis would lead to ___. hypertrophy atrophy spasms tics
atrophy
Through which structure is information sent on to the next cell?
axon
the hip (coxal) joint is a ___ synovial joint
ball and socket
Which of the following pairs of muscles are agonist-antagonists (that is, one flexes and the other extends) the forearm? biceps brachii and brachioradialis brachialis and brachioradialis triceps brachii and anconeus biceps brachii and triceps brachii anconeus and supinator
biceps brachii and triceps brachii
Which is NOT a component of the quadriceps femoris?
biceps femoris
list the muscles of the hamstring group
biceps femoris, semitendinosus, semimembranosus
The origin of the hyoglossus muscle is the mandible styloid process of temporal bone body of hyoid bone anterior surface of soft palate
body of hyoid bone
the impulses that initiate muscle contraction originates in the
brain or spinal cord
What makes up the CNS?
brain, spinal cord, some of the eyes
Define tract:
bundle of myelinated axons in the CNS
Define nerve:
bundles of myelinated axons in the PNS
How are voltage gated ion channels activated?
by reaching the voltage threshold of the cell
How are chemically gated (ligand gated) ion channels activated?
by the required and designated chemical reaching and stimulating the ion channel to open
The plantaris originates on the femur superior to the lateral condyle and inserts on the ______________.
calcaneus
What ion must flow into the presynaptic cell in order for it to release neurotransmitter? -calcium -magnesium -hydrogen -hydroxyl
calcium
This fleshy triangular muscle forms the shoulder muscle. serratus anterior pectoralis major deltoid biceps brachii
deltoid
The deltoid muscle inserts on the ___________ of the humerus.
deltoid tuberosity
what are common sites for the intramuscular injections
deltoid, gluteus medius, and the lateral side of the thigh in the midportion of the vastus lateralis muscle
Where does information arrive in a neuron?
dendrites
When the inside of the membrane becomes less negative, the membrane potential is said to be: repolarized. polarized. depolarized. neutral.
depolarized
When a neurotransmitter attaches to a chemically-gated sodium channel, the sodium channel briefly opens to allow sodium ions to diffuse in. This action produces what type of graded potential?: depolarizing graded potential hyperpolarizing graded potential polarizing graded potential repolarizing graded potential
depolarizing graded potential
a group of muscle cells stimulated bu a single motor neuron is known as a
motor unit
A muscle's insertion is where it attaches to the ____________ bone
moveable
All of the following are functions of the levator ani except supports and maintains position of pelvic viscera. functions as a sphincter at the anorectal junction. moves the coccyx in female during childbirth. constricts the urethra sphincter.
moves the coccyx in female during childbirth
What do motor neurons typically look like?
multipolar- cell body in the middle but on the side of the axon, axons on both sides going one way and axon terminal on the otherside
Which term best applies to a muscle that acts to move a bone away from the midline of the body?
oblique synergist flexor abductor adductor answer: abductor
How are graded potentials generated?
occur in response to the opening of a mechanical or ligand gated channel, causing the RMP to change depending on the amount of ions coming and leaving the cell
If three depolarizing graded potentials and two hyperpolarizing graded potentials occur in a dendrite at the same instant, what is the summation of their potentials equivalent to? -five graded potentials -one depolarizing graded potential -one hyperpolarizing graded potential -no potential at all
one depolarizing graded potential
origin and insertion of masseter
origin: maxilla and zygomatic arch insertion: mandible
origin and insertion of trapezius
origin: occipital bone, spine of c7, and all thoracic vertebrae insertion: acromion and spine of scapula, clavicle
rectus abdominus origin and insertion
origin: pubic crest and pubic symphysis insertion: xiphoid process and costal cartilages of ribs 5-7
origin and insertion of rhomboid serratus major
origin: ribs 1-8 insertion: vertebral (medial) border of scapula
origin and insertion of external oblique
origin: ribs 5-12 insertion: iliac crest and linea alba
origin and insertion of rhomboid major
origin: spinous processes T2-T5 insertion: vertebral (medial) border of scapula
origin and insertion of sternocleidomastoid
origin: sternum and clavicle insertion:mastoid process of temporal bone
The synapse consists of -a neuron cell body, axon, and terminus. -the myelin sheath and nodes of Ranvier. -presynaptic and post synaptic cell membranes separated by a synaptic cleft. -a neuron cell body, axon, terminus, myelin sheath, and nodes of Ranvier.
presynaptic and post synaptic cell membranes separated by a synaptic cleft.
Tendons attach to muscle and pull on bones to _______.
produce movement
action of rhomboid minor
protracts scapula
A type of membrane transport protein that uses ATP to move ions against their concentration gradient is known as a
pump
Exercise can produce a fashionable "six pack" of toned muscles. Which of the following muscles is involved in giving the appearance of this defined pack of muscles? external oblique internal oblique transversus abdominis rectus abdominis serratus anterior
rectus abdominis
action of rhomboid major
retracts scapula
Which neural circuit enables a single presynaptic stimulation to cause a postsynaptic cell to send a series of impulses? -simple circuit -convergent circuit -diverging circuit -parallel after-discharge circuit -reverberating circuit
reverberating circuit
Most of the strength in the shoulder joint comes from the ______________.
rotator cuff muscles
Which of the following muscles is known as the "tailor's muscle" because it helps you cross your legs so that you could sit with the heel of one limb resting on the knee of the other limb (in centuries past, sitting with crossed legs was the way tailor's, makers of clothing, would sit to do their sewing). sartorius gracilis adductor longus vastus intermedius semitendinosus
sartorius
After Serotonin has been released, some of it is returned to the presynaptic cell by -serotonin reuptake transporters in the membrane of the presynaptic cell. -phagocytes ingesting them and excreting them into the presynaptic cell. -a vacuum created by the presynaptic cell membrane. -gap junctions that temporarily form between the presynaptic and post synaptic cells.
serotonin reuptake transporters in the membrane of the presynaptic cell.
action of sternocleidomastoid
simultaneous contraction flexes neck; acting singly, laterally rotates head
If you are an endurance athlete, you especially rely on which type of skeletal muscle fiber to perform your sport?
slow oxidative fibers
Define graded potential:
small derivations in RMP.allow cells to communicate over short distances only, help us figure out where to change our action potential patterns
Which of the following will not open a gated channel? -voltage changes -mechanical changes -the ion being transported -ligands
the ion being transported
The generation of a graded potential is by -a sudden surge of ATP production on one side of the cell membrane -chemical reactions occurring near the cell membrane which change the cell's electrical state -feedback created in the axon of the neuron -the momentary opening of mechanically-gated or ligand-gated channels
the momentary opening of mechanically-gated or ligand-gated channels
When the term rectus appears in the name of a muscle, it indicates that
the muscle fascicles run parallel to the midline of the body
The electrical balance of the membrane potential can be changed from its resting potential by: a change in osmotic pressure. the activation of ion pumps. the opening of ion channels. the effect of leak channels.
the opening of ion channels.
An agonist muscle or muscle group is the one that is ________
the primary mover of a muscle
Some voltage-gated channels do not allow ions to pass through when their activation gate is open because
there is a second gate, an inactivation gate, that closes to block the channel.
How are mechanically gated ion channels activated?
through physical stimulation such as pressure, physical movement, vibration
quadriceps femoris consist of
vastus lateral and medial, vastus intermedius, rectus femoris
What do sensory neurons typically look like?
unipolar- cell body w/dendrites at the top, axon going in one direction and a axon terminal at the opposite end
What are the three STRUCTURAL classifications of neurons?
unipolar- cell body w/dendrites at the top, axon going in one direction and a axon terminal at the opposite end bipolar- cell body directly in the middle of axon going one way, multipolar- cell body in the middle but on the side of the axon, axons on both sides going one way and axon terminal on the otherside
What is myelin? Why is it important?
wraps all around the axon of a neuron and forms the myelin sheath, which helps to keep all of the action potential within the neuron consistently traveling down ot and out the axon terminal. it is essentially a insulator for a neurons action potential, increases speed action potential travels
What is the equilibrium potential of K+ (potassium's happy place)? Why is this important?
-80mV. not sure why its important but potassium will flow out of its channel when Na+ is flowing into the cell, making it too positive to stick around, so it leaves and makes the cell more negative, and causes more sodium to flow in to reach threshold
What is the resting membrane potential (RMP) of a muscle fiber?
-90mV
calcium binds to the troponin-tropomyosin complex and allows myosin access to the actin filaments T/F
-TRUE
what would increase contractile force?
-increasing number of motor units stimulated -increasing frequency of stimulation -recruitment of all 3 muscle fiber types
A nerve impulse (nerve action potential) elicits a muscle action potential in the following way
1) release of acetylcholine 2) activation fo ACh receptors 3) production of muscle action potential 4)Termination of ACh activity
approximate average number of spikes per second during a concentric isotonic contraction with a 5 lbs load is
100
how many thin filaments are there for every thick filament
2 thin for every 1 thick
the contraction cycle will end due to all of the following except:
A) Low ATP levels. B) End of electrical impulses from the nervous system. C) High Calcium levels. answer is C
Which list of organs contains smooth muscle tissue?
A) blood vessels, stomach, esophagus B) bladder, uterus, small intestine C) biceps brachii, triceps brachii (muscles of the arm) D)heart E) both blood vessels, stomach, esophagus and bladder, uterus, small intestine answer is E
Skeletal muscle is covered, surrounded and protected by various layers of connective tissue. Which layer of connective tissue would surround a bundle of muscle fibers (muscle cells)?
A) endomysium B) perimysium C) fascia D) epimysium E) hypodermis
Which of the following is not a function of skeletal muscle tissue?
A) shivering to generate body heat when you've become chilled B) holding your head up C) stabilizing joints and helping to maintain body positions D) moving your eyes from left to right as you read this question E) moving food through the small intestine
Fascicle
Bundle of muscle fibers wrapped in perimysium.
ATP causes myosin to form a cross T/F
FALSE
skeletal muscle can contract without nerve stimulation T/F
FALSE
during a muscle contraction, actin binds to myosin T/F
FALSE; Ca2+ ions bind to regulatory proteins(Troponin and tropomyosin) and trigger muscle contraction actin and myosin j interlock not bind i guesss
Acetylcholine activates gated ion channels on the sarcolemma, causing an influx of calcium ions into the muscle cell T/F
FALSE; causes a influc of sodium ions
ATP is hydrolyzed by the myosin tail T/F
FALSE; hydrolyzed by the head
the sarcomere is made entirely of actin filaments T/F
FALSE; is made of myosin and actin protein which, myosin has thick filaments and actin has thin filaments
acetylcholine is released by the sarcolemma across the synapse T/F
FALSE; is released by the somatic motor neuron into the synapse of neuromuscular junction
which protein does calcium bind to
TROPONIN
Titin is a very elastic molecule which pulls the muscle back into its original position after contraction T/F
TRUE
myofibrils are made of sarcomeres which are made of actin and myosin filaments T/F
TRUE
the function of the neurotransmitter is to cause an opening of soidum channels in the muscle cell membrane T/F
TRUE
the opening of sodium channels is essential for the initiation of an action potential in the muscle cell membrane: T/F
TRUE
the point of contact between a somatic motor neuron and a muscle cel is called a neuromuscular junction T/F
TRUE
without calcium ions, muscles couldnt contract: T/F
TRUE
a single action potential will create a single momentary contraction, not a continuous contraction T/F
TRUE; needs multiple/continuous action potentials
What is the neurotransmitter that is released from motor neurons to activate skeletal muscle?
acetylcholine, is released from one motor neuron into the synaptic cleft ti another motor neuron to signal skeletal muscle movement/reaction
muscle relaxtion requires which enzyme in order to clear the action potential?
acetylcholinesterase
correct sequence of muscle contraction process
action potential reaches synapse; calcium ions enter motor neuron; acetylcholine is released by motor neuron; ACh binds to gated ion channels on sarcolemma; sodium ions flood into the muscle cell, transporting the action potential, potassium flows out; calcium channels eventually open due to threshold being met and membrane becoming more positive due to the influx of sodium; calcium flows to the troponin-tropomyosin complex and binds ti head of troponin which then releases tropomyosin and allows myosin to lock with actin causing muscle contraction
What can bind to troponin?
calcium
the sarcoplasmic reticulum contains
calcium
what activates the sarcomere to contract?
calcium ions are released from the sarcoplasmic reticulum
how are binding sites on actin exposed?
calcium ions attach to troponin which slides tropomyosin off binding sites on actin
How can actin's active site become exposed so that myosin can bind to actin?
calcium needs to bind with troponin
at the end of contraction, the sarcomere returns to its relaxed position when:
calcium pumps(powered by ATP) remove calcium ions from the sarcomere and back into storage of the sarcoplasmic reticulum
termincal cisterns
dilated end sacs of the sarcoplasmic reticulum
during arm flexion the type of contraction that would occur in the triceps brachii is:
eccentric isotonic contraction
Muscle tissue has several important properties, such as electrical excitability. Another property of muscle tissue is that it is able to contract or extend, yet return to its original size and shape. Which property of muscle tissue is this?
elasticity
When oxygen is low inside a skeletal muscle cell, what happens to the pyruvic acid that is formed during glycolysis?
is converted to lactic acid
The contractile organelle of skeletal muscle fibers is
myofibrils
Which of the following molecules found in skeletal muscle cells binds oxygen that can later be used during aerobic metabolism to help generate ATP?
myoglobin
ATP binds to _______ at the end of muscle contraction
myosin
a powerstroke is caused by the ATP hydrolysis and phosphate release, binding and movement of multiple ______ molecules
myosin
The site where a somatic motor neuron releases acetylcholine to stimulate a skeletal muscle fiber is called the
neuromuscular junction
recruitment
process of increasing the number of active motor units to increase force developed by a muscle, weaker ones first then stronger ones are called for
What is the trigger that causes the sarcoplasmic reticulum to release calcium ions into the cell?
production of muscle action potential
myofibrils
protein structures that make up muscle fibers(striated), surrounded by a fluid filled system of membranous sacs called the sarcoplasmic reticulum
moto unit activation during eccentric isotonic contraction:
resists movement of load and enables controlled lengthening of muscle
What is the condition called when we cannot stop contraction of a muscle? What state is the organism in at this point?
rigor mortis, dead
In a relaxed muscle fiber, the ____________ stores _________. Release of ______ from the __________ of the sarcoplasmic reticulum triggers muscle contraction.
sarcoplasmic reticulum, stores Ca2+. Ca2+, terminal cisterns
which muscle fiber tupe usually has the lowest threshold for activation and thus is recruited first?
slow oxidative muscle fibers
Which type of muscle tissue is involuntary (can't be consciously controlled)?
smooth muscle and cardiac muscle
during eccentric isotonic contraction of the biceps brachii:
the arm is extended
muscle tone is
the small amount of tension in muscle due to alternating involuntary contraction of motor units
What is the function of t-tubules?
they act as a tunnel from the surface to the center of each muscle fiber to carry out muscle action potentials throughout muscle fibers. filled with interstitial fluid
Myofibrils contain two types of filaments:
thin and thick filaments
When a muscle fiber is at rest, _________ molecules cover the myosin binding site (actin's active site).
tropomyosin
Which of the 3 proteins in thin filaments covers the active sites on actin strands?
tropomyosin
binding sites on active are covered by:
tropomyosin(the rope things covering actin) & troponin(the stamp things holding down the rope things)
calcium binds to ______ to release _____ to uncover actin filaments
troponin; tropomyosin
what causes actin to slide toward the center of the sarcomere?
when troponin binds w calcium, releasing the grip of the troponin on the tropomyosin, allows myosin heads to bond with actin and slide toward the center