Anatomy: Chapters 9 and 10 Homework

Part complete The origin of the serratus anterior includes __________ ribs. ten eight six seven

eight

What is name given to the regularly spaced infoldings of the sarcolemma? View Available Hint(s) motor endplates transverse or T tubules sarcoplasmic reticulum terminal cisternae

transverse or T tubules

When the sarcomere is at rest, what is covering the active sites on actin? View Available Hint(s) cross-bridges troponin myosin tropomyosin

tropomyosin

Part complete At rest, active sites on the actin are blocked by ATP molecules. calcium ions. myosin molecules. troponin molecules. tropomyosin molecules.

tropomyosin molecules.

Part complete When calcium ion binds to troponin, muscle relaxation occurs. troponin shifts to expose the active sites on actin. myosin shortens. tropomyosin moves into the groove between the helical actin strands. active sites on the myosin are exposed.

tropomyosin moves into the groove between the helical actin strands.

Part complete When calcium is released inside a muscle cell, what does it bind to? View Available Hint(s) troponin actin tropomyosin myosin

troponin

What structure is the functional unit of contraction in a skeletal muscle fiber? View Available Hint(s) The cross bridge The triad The sarcomere The junctional folds of the sarcolemma

The sarcomere

Which of the following is not true of the deep fascia of the leg? an insertion for the majority of lower leg muscles separates anterior and posterior muscles prevents excess swelling of the muscles aids in venous return

an insertion for the majority of lower leg muscles

At the completion of supinator action, the palm is turned __________. posteriorly anteriorly medially laterally

anteriorly

When comparing slow fibers to fast fibers, slow fibers generate much more tension. are lacking myoglobin. take less time to reach peak tension. appear dark red. have much larger fiber diameters.

appear dark red.

Which of the following is not a recognized function of skeletal muscle? controlled involuntarily guard body entrances and exits maintain body temperature produce movement maintain posture

controlled involuntarily

Part complete Physical evidence that supports the sliding filament theory of muscle contraction includes constant distance between Z lines during contraction. decreased width of the A band during contraction. the I band and H band distance is constant during contraction. increased width of the I band during contraction. decreased width of the H band during contraction.

decreased width of the H band during contraction.

Part complete The smooth but steady increase in muscular tension that is produced by increasing the number of active motor units is called __________. wave summation complete tetanus treppe recruitment

recruitment

The origins of the levator scapula are from the ___________ of four cervical vertebrae. bodies transverse processes spinous processes fascia

transverse processes

The complex of a transverse tubule and two adjacent terminal cisternae is known as a(n) sarcomere. M line. zone of overlap. triad. free head.

triad.

The muscle that extends the arm while doing push-ups is the pectorals major. biceps brachii. triceps brachii. brachialis. deltoid.

triceps brachii.

Part complete At rest, the tropomyosin molecule is held in place by actin molecules. ATP molecules. troponin molecules. myosin molecules. calcium ions.

troponin molecules.

Inside a neuron, acetylcholine is contained within __________. View Available Hint(s) acetylcholine receptors the synaptic cleft the motor end plate vesicles

vesicles

When does a muscle contraction begin? when stored calcium ions are released from the sarcoplasmic reticulum into the sarcoplasm through gated calcium channels when potassium ions become irreversibly bound to storage proteins when calcium ions are pumped into the sarcoplasmic reticulum when stored potassium ions are released into the sarcoplasm through gated potassium channels

when stored calcium ions are released from the sarcoplasmic reticulum into the sarcoplasm through gated calcium channels

Which of the following best describes the term "Z line"? repeating unit of striated myofibrils protein that accounts for elasticity of resting muscle storage site for calcium ions largely made of myosin molecules where thin filaments are anchored

where thin filaments are anchored

Part complete The region of the sarcomere containing the thick and thin filaments is the H band. M line. A band. I band. Z line.

A band.

The cross bridge cycle is a series of molecular events that occur after excitation of the sarcolemma. What is a cross bridge? View Available Hint(s) Calcium bound to troponin Troponin bound to tropomyosin A myosin head bound to actin ATP bound to a myosin head

A myosin head bound to actin

Part complete A triad is composed of a T-tubule and two adjacent terminal cisternae of the sarcoplasmic reticulum. How are these components connected? View Available Hint(s) A series of proteins that control calcium release. Voltage-gated sodium channels. Myosin cross-bridge binding sites. Potassium leak channels.

A series of proteins that control calcium release.

The muscle tissue in the meat would probably not become stiff after death if it still had enough Calcium ATP Acetylcholine Sodium

ATP

After a power stroke, the myosin head must detach from actin before another power stroke can occur. What causes cross bridge detachment? View Available Hint(s) Calcium ions bind to troponin. ADP and inorganic phosphate are bound to the myosin head. ATP binds to the myosin head. Acetylcholine binds to receptors in the junctional folds of the sarcolemma.

ATP binds to the myosin head.

Part complete Action potential propagation in a skeletal muscle fiber ceases when acetylcholine is removed from the synaptic cleft. Which of the following mechanisms ensures a rapid and efficient removal of acetylcholine? View Available Hint(s) Acetylcholine is degraded by acetylcholinesterase. Acetylcholine is transported into the postsynaptic neuron by receptor-mediated endocytosis. Acetylcholine is transported back into the axon terminal by a reuptake mechanism. Acetylcholine diffuses away from the cleft.

Acetylcholine is degraded by acetylcholinesterase.

The neuromuscular junction is a well-studied example of a chemical synapse. Which of the following statements describes a critical event that occurs at the neuromuscular junction? View Available Hint(s) When the action potential reaches the end of the axon terminal, voltage-gated sodium channels open and sodium ions diffuse into the terminal. Acetylcholine binds to its receptor in the junctional folds of the sarcolemma. Its receptor is linked to a G protein. Acetylcholine is released and moves across the synaptic cleft bound to a transport protein. Acetylcholine is released by axon terminals of the motor neuron.

Acetylcholine is released by axon terminals of the motor neuron.

Calcium ions couple excitation of a skeletal muscle fiber to contraction of the fiber. Where are calcium ions stored within the fiber? View Available Hint(s) Calcium ions are stored in the transverse tubules. Calcium ions are stored in the nuclei. Calcium ions are stored in the mitochondria. Calcium ions are stored in the sarcoplasmic reticulum.

Calcium ions are stored in the sarcoplasmic reticulum.

What specific event triggers the uncovering of the myosin binding site on actin? View Available Hint(s) Calcium ions bind to troponin and change its shape. Sodium ions bind to troponin and change its shape. Calcium release channels open in the sarcoplasmic reticulum, and calcium levels rise in the sarcoplasm. Calcium ions bind to tropomyosin and change its shape.

Calcium ions bind to troponin and change its shape.

Which of the following is most directly responsible for the coupling of excitation to contraction of skeletal muscle fibers? View Available Hint(s) Calcium ions. Acetylcholine. Action potentials. Sodium ions.

Calcium ions.

What causes calcium to be released from the sarcoplasmic reticulum? (Module 9.8A) Calcium is released when an action potential reaches the triad. Calcium is released when myosin heads bind to actin. Calcium is released when an action potential travels down the motor neuron. Calcium is released when acetylcholine binds acetylcholine receptors. Calcium is released when an action potential is generated at the neuromuscular junction.

Calcium is released when an action potential reaches the triad.

Excitation of the sarcolemma is coupled or linked to the contraction of a skeletal muscle fiber. What specific event initiates the contraction? View Available Hint(s) Action potentials propagate into the interior of the skeletal muscle fiber. Voltage-sensitive proteins change shape. Sodium release from the sarcoplasmic reticulum initiates the contraction. Calcium release from the sarcoplasmic reticulum initiates the contraction.

Calcium release from the sarcoplasmic reticulum initiates the contraction.

Contrast fast fibers with slow fibers in terms of diameter, glycogen reserves, myoglobin content, and relative abundance of mitochondria. (Module 9.14A) Compared with slow fibers, fast fibers have a smaller diameter, smaller glycogen reserves, less myoglobin, and relatively fewer mitochondria. Compared with slow fibers, fast fibers have a larger diameter, smaller glycogen reserves, less myoglobin, and more mitochondria. Compared with slow fibers, fast fibers have a larger diameter, larger glycogen reserves, less myoglobin, and relatively fewer mitochondria. Compared with slow fibers, fast fibers have a smaller diameter, smaller glycogen reserves, more myoglobin, and more mitochondria. Compared with slow fibers, fast fibers have a smaller diameter, larger glycogen reserves, more myoglobin, and more mitochondria.

Compared with slow fibers, fast fibers have a larger diameter, larger glycogen reserves, less myoglobin, and relatively fewer mitochondria.

When does cross bridge cycling end? View Available Hint(s) Cross bridge cycling ends when ATP binds to the myosin head. Cross bridge cycling ends when calcium ions are passively transported back into the sarcoplasmic reticulum. Cross bridge cycling ends when calcium release channels in the sarcoplasmic reticulum open. Cross bridge cycling ends when sufficient calcium has been actively transported back into the sarcoplasmic reticulum to allow calcium to unbind from troponin.

Cross bridge cycling ends when sufficient calcium has been actively transported back into the sarcoplasmic reticulum to allow calcium to unbind from troponin.

What chemical changes most likely happen during aging to make meat regain its tenderness? Troponin changes position, moving tropomyosin Myosin heads detach from the active sites actin Myofilaments decompose and break down Calcium ions are pumped into the sarcoplasmic reticulum so that contraction ceases

Myofilaments decompose and break down

Part complete Excitation-contraction coupling is a series of events that occur after the events of the neuromuscular junction have transpired. The term excitation refers to which step in the process? View Available Hint(s) Excitation refers to the shape change that occurs in voltage-sensitive proteins in the sarcolemma. Excitation, in this case, refers to the propagation of action potentials along the sarcolemma. Excitation refers to the release of calcium ions from the sarcoplasmic reticulum. Excitation refers to the propagation of action potentials along the axon of a motor neuron.

Excitation, in this case, refers to the propagation of action potentials along the sarcolemma.

The area in the center of the A band that contains no thin filaments is the I band. H band. M line. Z line. zone of overlap.

H band.

Which of the following is not true of the muscular system? It depends upon calcium stored and released from the skeletal system. It depends upon the nervous system to stimulate skeletal muscle tissue to contract. It depends upon calcitonin and parathyroid hormone levels to maintain calcium homeostasis. It depends upon the integumentary system to protect muscles. It depends upon the cardiovascular system to provide the hemoglobin stored in slow muscle fibers.

It depends upon the cardiovascular system to provide the hemoglobin stored in slow muscle fibers.

Part complete Summarize the sliding filament theory. (Module 9.4C) It is the process of sarcomere shortening caused by the sliding of thin and thick filaments past another. It is the theory that excitation-contraction coupling leads to muscle fiber relaxation. It is the process that causes an action potential to travel down the T tubules into the sarcolemma. It is the theory that Z lines will move further from each other when the thin and thick filaments slide past each other. It is the theory that sarcomeres lengthen during the sliding of the thin and thick filaments past each other.

It is the process of sarcomere shortening caused by the sliding of thin and thick filaments past another.

Part complete Which statement about the microscopic anatomy of skeletal muscle fibers is not true? Each fiber has many nuclei. Muscle fibers are continuous from tendon to tendon. Cross striations result from the lateral alignment of thick and thin filaments. Multiple myofibrils link end-to-end along length of the muscle cell. Tubular extensions of the sarcolemma penetrate the fiber transversely.

Multiple myofibrils link end-to-end along length of the muscle cell.

Define muscle hypertrophy and muscle atrophy. (Module 9.15A) Muscle hypertrophy is an increase in the vascularization of the muscle cells and muscle atrophy is a decrease in the vascularization of the muscle cells. Muscle hypertrophy is an increase in the size of the muscle cells and muscle atrophy is a decrease in the number of muscle cells. Muscle hypertrophy is an increase in the number of muscle cells and muscle atrophy is a decrease in the size of the muscle cells. Muscle hypertrophy is an increase in the size of the muscle cells and muscle atrophy is a decrease in the size of the muscle cells. Muscle hypertrophy is an increase in the number of muscle cells and muscle atrophy is a decrease in the number of muscle cells.

Muscle hypertrophy is an increase in the size of the muscle cells and muscle atrophy is a decrease in the size of the muscle cells.

Part complete When a skeletal muscle fiber contracts, which of the following does not occur? The zones of overlap get larger. The Z lines get closer together. The width of the A band remains constant. The H bands and I bands get smaller. Myosin and actin filaments decrease in length.

Myosin and actin filaments decrease in length.

Prior to the death of the cow that the meat came from, the living skeletal muscle cells used energy (hydrolyzed ATP) in order to Perform a "power stroke" to pull on actin Send acetylcholine across the synaptic gap Reactivate myosin heads Release calcium ions from the sarcoplasmic reticulum

Reactivate myosin heads

Calcium entry into the axon terminal triggers which of the following events? View Available Hint(s) Acetylcholine is released into the cleft by active transporters in the plasma membrane of the axon terminal. Cation channels open and sodium ions enter the axon terminal while potassium ions exit the axon terminal. Acetylcholine binds to its receptor. Synaptic vesicles fuse to the plasma membrane of the axon terminal and release acetylcholine.

Synaptic vesicles fuse to the plasma membrane of the axon terminal and release acetylcholine.

How does the myosin head obtain the energy required for activation? View Available Hint(s) The energy comes from oxidative phophorylation. The energy comes from the hydrolysis of GTP. The energy comes from the hydrolysis of ATP. The energy comes from the direct phosphorylation of ADP by creatine phosphate.

The energy comes from the hydrolysis of ATP.

Sodium and potassium ions do not diffuse in equal numbers through ligand-gated cation channels. Why? View Available Hint(s) The inside surface of the sarcolemma is negatively charged compared to the outside surface. Potassium ions diffuse inward along favorable chemical and electrical gradients. The inside surface of the sarcolemma is negatively charged compared to the outside surface. Sodium ions diffuse inward along favorable chemical and electrical gradients. The outside surface of the sarcolemma is negatively charged compared to the inside surface. Sodium ions diffuse outward along favorable chemical and electrical gradients. The outside surface of the sarcolemma is negatively charged compared to the inside surface. Potassium ions diffuse outward along favorable chemical and electrical gradients.

The inside surface of the sarcolemma is negatively charged compared to the outside surface. Sodium ions diffuse inward along favorable chemical and electrical gradients.

What happens immediately after the myosin head binds to the active site on actin? View Available Hint(s) ATP binds to the myosin head. Tropomyosin moves away from the active site on actin. The myosin head detaches from the active site on actin. The myosin head pivots, moving the actin strand.

The myosin head pivots, moving the actin strand.

Which of the following is characteristic of Type II-A skeletal muscle fibers? These fibers are known as fast-twitch glycolytic fibers. These fibers are known as fast-twitch oxidative fibers. These fibers are known as slow-twitch oxidative fibers. These fibers use lipids, carbohydrates, and amino acids for aerobic metabolism.

These fibers are known as fast-twitch oxidative fibers.

What is the relationship between the number of motor neurons recruited and the number of skeletal muscle fibers innervated? View Available Hint(s) Typically, hundreds of skeletal muscle fibers are innervated by a single motor neuron. Motor neurons always innervate thousands of skeletal muscle fibers. A skeletal muscle fiber is innervated by multiple motor neurons. A motor neuron typically innervates only one skeletal muscle fiber.

Typically, hundreds of skeletal muscle fibers are innervated by a single motor neuron.

Can a skeletal muscle contract without shortening? Why or why not? (Module 9.11C) No, because muscles contract only when the muscle tension exceeds the load. No, because muscles can only generate tension while shortening, never during lengthening. Yes, because muscles can still contract during an isotonic contraction when the tension is at a constant level. No, because muscles contract only when the muscle tension is less than the load. Yes, because muscles can still contract during an isometric contraction when the muscle tension is equal to the load.

Yes, because muscles can still contract during an isometric contraction when the muscle tension is equal to the load.

Part complete Tetanus is most likely to result from which condition? a deep puncture wound, such as that from a nail a shallow, open cut that bleeds freely and flushes the site exposure to bacteria, which produce toxins that block ACh release exposure to a virus that attacks motor neurons in the spinal cord and brain

a deep puncture wound, such as that from a nail

Myosin molecules form cross-bridges when they attach to __________. View Available Hint(s) actin calcium troponin tropomyosin

actin

Which of the following proteins contains the active site involved in cross-bridge formation? View Available Hint(s) myosin tropomyosin troponin actin

actin

Part complete Which process can, by itself, power the greatest number of twitches, based on the energy sources available in a typical muscle fiber? breakdown of free ATP aerobic metabolism of glycogen glycolysis breakdown of creatine phosphate

aerobic metabolism of glycogen

What causes the vesicles inside a neuron to fuse with the plasma membrane? View Available Hint(s) an action potential in the muscle fiber an action potential in the neuron acetylcholine binding to acetylcholine receptors acetylcholine being broken down by acetylcholinesterase

an action potential in the neuron

Twelve-year-old Aaron tried out for the Little League baseball team and was chosen as a pitcher. One day, after a few months of practice and games, Aaron's father told him, "Hey, kid, you're really getting some muscle definition there! You're going to be a major league pitcher someday, with muscles like that!" Which of Aaron's muscles in particular do you think were growing stronger and getting larger as a result of his pitching? mentalis, risorius, levator anguli oris deltoid, triceps brachii, and brachioradialis triangularis, masseter, trapezius sartorius, soleus, rectus femoris peroneus longus, biceps femoris, gastrocnemius

deltoid, triceps brachii, and brachioradialis

During the ________ phase of action potential development, voltage-gated sodium channels are open. repolarization threshold depolarization refractory

depolarization

Part complete ATP binding leads to which of the following actions? View Available Hint(s) exposure of active sites on actin cross-bridge formation detaching and resetting cross-bridges pivoting of the myosin head

detaching and resetting cross-bridges

Which type of contraction results in elongation of the muscle? eccentric contraction incomplete tetanus isometric contraction concentric contraction

eccentric contraction

The delicate connective tissue that surrounds the skeletal muscle fibers and ties adjacent muscle fibers together is the periosteum. endomysium. superficial fascia. perimysium. epimysium.

endomysium.

Part complete Action potentials travel the length of the axons of motor neurons to the axon terminals. These motor neurons __________. View Available Hint(s) extend from the spinal cord to the sarcolemma of a skeletal muscle fiber extend from the brain or spinal cord to the sarcolemma of a skeletal muscle fiber arise in the epimysium of a skeletal muscle and extend to individual skeletal muscle fibers extend from the brain to the sarcolemma of a skeletal muscle fiber

extend from the brain or spinal cord to the sarcolemma of a skeletal muscle fiber

The gluteus maximus is the most powerful muscle during __________. flexion extension medial rotation lateral rotation

extension

Large-diameter, densely packed myofibrils, large glycogen reserves, and few mitochondria are characteristics of slow fibers. intermediate fibers. red muscles. fast fibers. fatty muscles.

fast fibers.

Part complete The iliacus and the psoas major muscles are collectively known as the ____________ muscle because they share a common insertion on the __________ of the femur. psoasiliacus; lesser trochanter iliopsoas; greater trochanter psoasiliacus; greater trochanter iliopsoas; lesser trochanter

iliopsoas; lesser trochanter

Part complete The majority of the fibers of the gluteus maximus insert onto the __________. inferior border of the os coxae superior border of the os coxae iliotibial tract gluteal tuberosity

iliotibial tract

The tensor fasciae latae stabilizes the hip joint and the __________ joint. ankle sacral knee elbow

knee

Both the Psoas major muscle and iliacus muscle insert on the __________. lesser trochanter of the femur greater trochanter of the femur intertrochanteric crest linea alba of the femur

lesser trochanter of the femur

The muscle weakness of myasthenia gravis results from loss of acetylcholine receptors in the end-plate membrane. excessive acetylcholinesterase that destroys the neurotransmitter. insufficient acetylcholine release from presynaptic vesicles. the motor neuron action potential being too small to shock the muscle fibers. All of the answers probably contribute to the muscle weakness.

loss of acetylcholine receptors in the end-plate membrane.

Part complete Myofibrils are __________. View Available Hint(s) bundles of muscle cells inside a whole muscle connections between actin and myosin proteins that cover active sites on actin made of a series of sarcomeres

made of a series of sarcomeres

The Na+/K+ ion pump is responsible for maintaining the sodium/potassium concentration gradients constant. transferring messages from enzyme-linked receptors to the cell nucleus. initiating action potentials. diffusing chloride across the plasma membrane. amplifying signals using ATP.

maintaining the sodium/potassium concentration gradients constant.

The neuromuscular junction is a connection between a neuron and a __________. View Available Hint(s) vesicle muscle fiber myofibril synaptic terminal

muscle fiber

In an isotonic contraction, tension rises and falls but the muscle length is constant. muscle tension exceeds the load and the muscle lifts the load. the peak tension is less than the load. many twitches fuse into one.

muscle tension exceeds the load and the muscle lifts the load.

Determine the correct structural hierarchy of skeletal muscles from microscopic to gross levels. fascicle - myofibril - fiber - muscle myofibril - fiber - muscle - fascicle myofibril - fiber - fascicle - muscle fiber - myofibril - muscle - fascicle

myofibril - fiber - fascicle - muscle

Which of the following is involved in the power stroke? View Available Hint(s) Z lines myosin tropomyosin myofibrils

myosin

Rigor mortis __________. occurs as the sarcoplasmic reticulum deteriorates, releasing calcium ions is independent of environmental factors involves appendicular skeletal muscles only is due to the loss of acetylcholine receptors at the neuromuscular junctions

occurs as the sarcoplasmic reticulum deteriorates, releasing calcium ions

Part complete Acetylcholine receptors are primarily located __________. View Available Hint(s) on the synaptic terminal on the motor end plate inside the muscle fiber inside vesicles

on the motor end plate

All of these muscles produce lateral rotation at the hip except the obturator internus gluteus maximus pectineus piriformis quadrats femoris

pectineus

Which of the following is an ion that is more concentrated inside the cell than outside? hydrogen chloride calcium sodium potassium

potassium

The advantage of having many nuclei in a skeletal muscle fiber is the ability to produce more ATP with little oxygen. contract. store extra DNA for metabolism. produce large amounts of the muscle proteins needed for muscle contraction. All of the answers are correct.

produce large amounts of the muscle proteins needed for muscle contraction.

The role of acetylcholinesterase in the neuromuscular junction is to __________. View Available Hint(s) release acetylcholine from the synaptic terminal remove acetylcholine from the synaptic cleft increase the sodium permeability of the motor end plate generate a muscle action potential

remove acetylcholine from the synaptic cleft

If potassium channels were blocked, the ________ phase of the action potential would not occur normally. threshold repolarization depolarization refractory

repolarization

After death, muscle fibers run out of ATP and calcium begins to leak from the sarcoplasmic reticulum into the sarcoplasm. This results in a condition known as oxygen debt. tetany. treppe. depolarization. rigor mortis.

rigor mortis.

The repeating contractile unit of a skeletal muscle fiber is the myofilament. sarcolemma. sarcoplasmic reticulum. sarcomere. myofibril.

sarcomere.

Z lines define the edges of which of the following? View Available Hint(s) myosin myofibrils cross-bridges sarcomeres

sarcomeres

Part complete The anterior muscles of the thigh that originate on the os coxae are __________. vastus lateralis; vastus medialis rectus femoris; vastus medialis sartorius; rectus femoris sartorius; vastus medialis

sartorius; rectus femoris

Part complete The type of muscle fiber that is most resistant to fatigue is the ________ fiber. high-density intermediate anaerobic slow fast

slow

Which type of muscle fiber predominates in the leg muscles of endurance athletes, such as long-distance runners? (Module 9.14C) slow fibers fast fibers intermediate fibers

slow fibers

The rhomboid minor muscle sits __________. superficial to the rhomboid major inferior to the rhomboid major deep to the rhomboid major superior to the rhomboid major

superior to the rhomboid major

Part complete The end of a neuron, where acetylcholine-filled vesicles are located, is called the __________. View Available Hint(s) motor end plate synaptic cleft acetylcholine receptor synaptic terminal

synaptic terminal

An action potential in the muscle fiber causes __________. View Available Hint(s) acetylcholinesterase to break down acetylcholine the release of acetylcholine into the synaptic cleft acetylcholine to bind to receptors on the motor end plate the muscle fiber to contract

the muscle fiber to contract

Part complete Acetylcholine binds to its receptor in the sarcolemma and triggers __________. View Available Hint(s) the opening of ligand-gated anion channels the opening of ligand-gated cation channels the opening of voltage-gated calcium channels the opening of calcium-release channels

the opening of ligand-gated cation channels

What is the synaptic cleft? View Available Hint(s) the border between the motor end plate and the sarcolemma the region of the neuron containing synaptic vesicles the step where acetylcholinesterase (AChE) breaks down, or cleaves, acetylcholine the space between the synaptic terminal and the motor end plate

the space between the synaptic terminal and the motor end plate

Myosin molecules form what part of the sarcomere? View Available Hint(s) thick filament actin thin filament tropomyosin

thick filament