anatomy and physiology chapter 10

During muscle contractions ,thin filaments are pulled towards the A)Z disc. B)H zone. C)M line. D)A band. E)I band

M line

Cross bridges are formed during muscle contraction when _____ binds to _____. A)myosin;troponin B)actin;troponin C)myosin;actin D)actin;myosin E)actin;tropomyosin

myosin;actin

In a neuromuscular junction,the effect of acetylcholine (ACh)binding to receptors on the motor end plate lasts only briefly due to A)rapid uptake of the ACh into the myofiber. B)endocytosis of the ACh receptor into the myofiber. C)rapid destruction of ACh in the synaptic cleft by acetylcholinesterase. D)rapid destruction of ACh in the synaptic cleft by monoamine oxidase. E)diffusion of the ACh out of the synaptic cleft.

rapid destruction of ACh in the synaptic cleft by acetylcholinesterase.

Which type of muscle tissue is capable of undergoing the stress-relaxation response when stretched? A)cardiac muscle fibers B)fast glycolytic fibers C)fast oxidative-glycolytic fibers D)multiunit smooth muscle fibers E)single-unit smooth muscle fibers

single-unit smooth muscle fibers

Why will and individual who lifts weights build larger muscles? A)skeletal muscles are hyperplasic and respond to stress B)skeletal muscle myofibrils and cells increase in number C)skeletal muscles increase number of myofibrils but not number of cells D)skeletal muscles signal satellite cells to increase number of cells

skeletal muscles increase number of myofibrils but not number of cells

A brief contraction of all muscle fibers in a motor unit in response to a single action potential moving down the somatic motor neuron is known as A)unfused tetanus. B)fused tetanus C)wave summation. D)refractory period. E)twitch contraction.

twitch contraction

Which regions of the sarcomere contain thick filaments? Select all that apply A)zone of overlap B)A band C)H zone D)I band

zone of overlap A band H zone

In skeletal muscles,the combined amounts of creatine phosphate and ATP provide enough energy for the muscle to contract maximally for approximately A)15 seconds. B)15 minutes. C)1)5 minutes. D)5 seconds. E)one minute.

15 seconds.

When an athlete performs a pull up (raising their chin to a bar while their body hangs),the process of pulling the body up so the chin can touch the bar is A)Concentric B)Eccentric C)Isometric

Concentric

What is the result of acetylcholine attaching to the ligand gates of the motor end plate? A)the sarcolemma increases permeability to sodium B)the positive charge of the sarcolemma decreases C)calcium ions will be actively transported into the SR D)calcium voltage gates on the neurolemma are inactive

the sarcolemma increases permeability to sodium

Which age group would be most susceptible to an increase in slow oxidative muscle fibers? A)pre-teens (9-12 years old) B)teenagers (13-19 years old) C)20-29 years old D)30+ years

30+ years

For the muscle to contract and relax,what must be present (choose all that apply)? A)ATP B)calcium ions C)Ach D)sodium ions

ATP calcium ions Ach

What energizes the myosin head? A)acetylcholine B)calcium ions C)Phosphate release D)ATP hydrolysis reaction E)ADP synthesis

ATP hydrolysis reaction

For crossbridges to occur,what events must happen? Select all that apply. A)ATPase breaks down ATP. B)calcium ions be present in the sarcoplasm. C)myosin binding sites be exposed. D)high amounts of sodium be present in the synaptic cleft E)Acetylcholine be present in the synaptic cleft

ATPase breaks down ATP. calcium ions be present in the sarcoplasm. myosin binding sites be exposed.

Which region of a sarcomere contain thin filaments? A)I band B)A band C)H zone D)Both I band and A band.

Both I band and A band.

When an athlete performs a pull up (raising their chin to a bar while their body hangs),the process of lowering the body down is A)Concentric B)Eccentric C)Isometric

Eccentric

When an athlete is preparing to perform a pull up,they hang from the bar.At this point,they are performing what type of contractions? A)Concentric B)Eccentric C)Isometric

Isometric

Diltiazem is a calcium channel blocker,reducing free intracellular calcium.What stage of the myogram would be affected immediately? A)Latent period B)Contraction period C)Relaxation period D)All myogram stages are affected

Latent period

Thapsigargin is a potent calcium ATPase pump inhibitors.What state of the myogram would be affected immediately? A)Latent period B)Contraction period C)Relaxation period D)All myogram stages are affected

Relaxation period

Myasthenia Gravis is an autoimmune disorder that targets the ACh receptors at the NMJ and ultimately reduces the number of available receptors.Predict what happens if you treat the patient with a drug that inhibits the activity of acetylcholinesterase? A)The drug will prevent contraction. B)The drug will cause a weak contraction. C)The drug will increase contraction. D)The drug will cause spasm. )

The drug will increase contraction.

Which statement explains the sarcomere appearance change during a muscle contraction? A)The light A bands remain at a constant length. B)The I bands lengthen. C)The I bands will only consist of thin filament. D)The h zone shortens as actin filaments slide towards the m-line.

The light A bands remain at a constant length.

Writer's cramp can occur in Anatomy and Physiology lecture class.What factor would most likely contribute to the muscles not being able to relax? A)oxygen being delivered by myoglobin and hemoglobin B)a deficit of ATP keeping myosin from detaching C)calcium being pumped into the sarcoplasmic reticulum D)ACh being degraded by AChE

a deficit of ATP keeping myosin from detaching

The opening of ligand gates on the sarcolemma is directly caused by A)acetylcholine attachment. B)calcium influx into the motor neuron . C)sodium influx into the muscle fiber. D)acetylcholinesterase activity E)all choices are correct

all choices are correct

After prolonged strenuous exercise has stopped,heavy breathing will often continue for several minutes in order to provide the oxygen needed to A)convert the lactic acid produced during exercise back into glycogen. B)resynthesize creatine phosphate. C)replace oxygen displaced from muscle myoglobin.

all of these choices are correct

Which ATP production would be sufficient to run in place for one minute? A)creatine phosphate B)anaerobic cellular respiration C)aerobic cellular respiration

anaerobic cellular respiration

Which correctly lists the sequence of structures that action potentials must move through to excite skeletal muscle contraction? A)sarcolemma,axon of neuron,T tubules B)T tubules,sarcolemma,myofilament C)muscle fiber,axon of neuron,myofibrils D)axon of neuron,sarcolemma,T tubules E)myofibrils,myofilaments,mitochondria

axon of neuron,sarcolemma,T tubules

Smooth muscle tone is maintained by the prolonged presence of [_____] in the muscle cell's cytosol? A)ATP B)calcium ions C)sodium ions D)acetylcholine E)oxygen

calcium ions

At the neuromuscular junction,_______must enter the synaptic end bulb to stimulate the release of ____________,which binds to ligand gates so ________can enter the muscle fiber. A)calcium ions;ACh,sodium ions B)sodium ions,calcium ions,ACh C)ACh,calcium ions,sodium ions D)sodium ions,ACh,calcium ions E)calcium ions,sodium ions,ACh

calcium ions;ACh,sodium ions

Contraction of myofibrils within a muscle fiber begins when A)sodium enters the muscle fiber B)acetylcholine binds to ligand gates C)calcium is released from the sarcoplasmic reticulum D)an action potential travels t-tubules E)calcium is moved into the sarcoplasmic reticulum

calcium is released from the sarcoplasmic reticulum

Which type of muscle tissue contracts when excited by their own autorhythmic muscle fibers? A)cardiac muscle B)slow twitch oxidative skeletal muscle C)multi-unit smooth muscle D)fast twitch glycolytic skeletal muscle

cardiac muscle

Myofibrils contain what type of proteins? Select all that apply. A)contractile proteins. B)regulatory proteins. C)structural proteins. D)tensile proteins

contractile proteins. regulatory proteins. structural proteins.

The zone of overlap increases during the A)latent period B)contraction period C)relaxation period D)absolute refractory period E)relative refractory period

contraction period

The relaxation phase of a muscle contraction is often prolonged in a fatigued muscle,raising the likelihood of fused summation of action potentials causing painful disturbances to a skeletal muscle.What disturbance is being described? A)fasciculation B)tremor C)fibrillation D)cramp

cramp

Which protein is used to reinforce the sarcolemma and help transmit the tension generated by the sarcomeres to the tendons? A)troponin B)tropomyosin C)myosin D)actin E)dystrophin

dystrophin

The outermost layer of connective tissue surrounding a skeletal muscle is the A)tendon B)ligament C)endomysium D)epimysium E)perimysium

epimysium

Which property of muscle gives it the ability to stretch without damage? A)electrical excitability B)contractility C)extensibility D)elasticity

extensibility

World class shot-putters will have a higher percentage of ______in their arm muscles. A)slow oxidative fibers B)fast oxidative fibers C)fast glycolytic fibers

fast glycolytic fibers

Which of the regions of a sarcomere contain titin? A)the A band only B)the H zone only C)the zone of overlap only D)from M line to Z disc E)the I band only

from M line to Z disc

After the fusion of myoblasts,the muscle fiber loses its ability to A)grow B)lengthen C)contract D) go through mitosis

go through mitosis

Strength training would result in A)atrophy of fast oxidative-glycolytic fibers B)hypertrophy of fast oxidative-glycolytic fibers C)hyperplasia of fast oxidative-glycolytic fibers D)conversion of slow oxidative fibers to fast oxidative-glycolytic fibers

hypertrophy of fast oxidative-glycolytic fibers

Motor unit recruitment occurs when there is a(n)[increase] in the number of active motor units within a skeletal muscle. A)increase B)decrease C)no change

increase

Which microscopic structure is found only in the cardiac muscle tissue? A)myosin B)tropomyosin C)sarcomeres D)intercalated discs E)striations

intercalated discs

Which term describes a somatic motor neuron and all the skeletal muscle fibers it stimulates? A)synapse B)motor unit C)neuromuscular junction D)motor end plate

motor unit

Which function do all three muscles perform? A)moving and storing material throughout the body B)generating heat through contractions C)stabilizing the movement of joints D)promoting movement of body structures

moving and storing material throughout the body

Which disorder occurs when little to no proteins are produced to support the sarcolemma? A)muscular hypertrophy B)muscular atrophy C)fibromyalgia D)myasthenia gravis E)muscular dystrophy

muscular dystrophy

Muscle damage can be indicated by... A)myoglobin found in blood. B)few mitochondria located in muscle fibers. C)low concentration of creatine kinase in the sarcoplasm. D)slow myosin ATPase. E)high amount of glycogen in the sarcoplasm.

myoglobin found in blood.

Which functions as a motor protein in all three types of muscle tissue? A)actin B)myosin C)troponin D)titin E)tropomyosin

myosin

Place the muscle tissue type in order from least to most ability to regenerate. A)smooth,skeletal,cardiac B)skeletal,cardiac,smooth C)cardiac,smooth,skeletal D)skeletal,smooth,cardiac E)cardiac,skeletal,smooth

skeletal,cardiac,smooth

Which characteristics describe both skeletal and cardiac muscle? A)striations B)autorhymicity C)cell shape D)autonomic control E)somatic control

striations

Skeletal muscle contraction is triggered to begin when calcium is released from A)myofibrils B)mitochondria C)terminal cisterns of sarcoplasmic reticulum D)T-tubules

terminal cisterns of sarcoplasmic reticulum

Mitochondrial activity in skeletal muscle cells are usually efficient,but can have limited ATP production if A)there is pyruvic acid accumulation. B)there is limited O2 availability C)CO2 is produced as a waste product.

there is limited O2 availability

Why would cardiac muscles have longer refractory periods than skeletal muscles.Choose the best answer? A)to preserve the normal rhythm of the heart and prevent fatigue B)the muscle types contain different contractile proteins C)skeletal muscle is autorhythmic D)skeletal muscles have prolonged calcium influx E)cardiac muscle is not dependent on aerobic respiration to produce ATP

to preserve the normal rhythm of the heart and prevent fatigue