Practice Questions - Muscular system
Which of the following muscles increases the angle between the bones of the fingers and hand? A. Extensor digitorum B. Extensor carpi ulnaris C. Flexor digitorum profundus D. Abductor pollicis longus
a. extensor digitorum
Which muscle and bone listed below do NOT work together in combination? A. Humerus and biceps femoris B. Quadriceps and tibia C. Femur and gluteal muscles D. Radius and biceps brachii
a. humerus and biceps femoris
The space between the ribs is filled with: A. Intercostal muscle B. Costal cartilage C. Intercostal space D. Pleura
a. intercostal muscle
Smooth muscle is different from skeletal muscle because smooth muscle: A. Is found in the walls of arteries B. Can be voluntarily contracted C. Has many nuclei in a cell D. Has intercalated discs between cells
a. is found in the walls of arteries
What is the role of acetylcholine in muscle cell contraction? A. It is a neurotransmitter. B. It binds to troponin causing it to change shape. C. It supplies the energy for contraction. D. It engages with the binding site on actin.
a. it is a neurotransmitter
Which is the largest of the structures in a muscle fibre? A. Myofibril B. Myofilament C. Myosin D. Myopic
a. myofibril
On what part of the body is the serratus anterior muscle located? A. On the front of the torso B. On the lower back C. At the front of the thigh D. In the serratus region
a. on the front of the torso
Which muscle named below includes its origin and insertion? A. Pubococcygeus B. Sartorius C. External abdominal obliques D. Serratus anterior
a. pubococcygeus
Which muscles extend the leg? A. Quadriceps B. Hamstrings C. Gluteus muscles D. Soleus, gastrocnemius and tibialis anterior
a. quadriceps
All of the following structures are part of a muscle cell except one. Which one? A. Sarcoma B. Sarcolemma C. Sarcoplasm D. Sarcoplasmic reticulum
a. sarcoma (sarcoma is a cancer of connective tissues)
A skeletal muscle fibre (cell) consists of many sections (units) which contract. What is the name given to one of the units that contract? A. Sarcomere B. Sarcolemma C. Sarcoplasm D. Fasciculus
a. sarcomere
Which of the following muscle structures is the smallest? A. Sarcomere B. Fasciculus C. Myofibril D. Muscle fibre
a. sarcomere
What is the gluteus maximus named for? Its: A. Size B. Shape C. Action D. Origin and insertion
a. size
Which of the following describes skeletal muscle? A. Striated, voluntary, multinucleate, individually named. B. Striated, branched, uninucleate, involuntary. C. Not striated, uninucleate, voluntary, individually named. D. Not striated, multinucleate, involuntary, with intercalated discs.
a. striated, voluntary, multinucleate, individually named
Which feature is shared by cardiac muscle cells and skeletal muscle cells? A. Striations B. Intercalated discs C. Branching D. Involuntary nature
a. striations
During muscle cell contraction, what happens because of Ca++ binding to troponin? A. The binding site on actin is uncovered. B. Acetylcholine (ACh) is released. C. The cross-bridge disengages from the thin filament. D. ATP hydrolyses to ADP.
a. the binding site on actin is uncovered
What information is contained in the muscle name "biceps brachii"? A. The muscle location and the number of origins B. The number of origins and the muscle action C. The muscle size and location in the body D. The muscle's shape and its action
a. the muscle location and the number of origins
Why does anaerobic respiration occur during vigorous exercise? A. There may be insufficient oxygen supplied to the muscle cells. B. Carbon dioxide builds up in the respiring muscle cells. C. Anaerobic respiration releases more energy from glucose than aerobic respiration. D. During anaerobic respiration enzymes make more ATP than during aerobic exercise.
a. there may be insufficient oxygen supplied to the muscle cells
Which muscle is located on the front of the anatomical leg? A. Tibialis anterior B. Rectus femoris C. Sartorius D. Flexor carpi radialis
a. tibialis anterior
What is the protein of thin myofilaments in a skeletal muscle cell? (Two answers) A. Tropomyosin B. Myosin C. Actin D. Acetylcholine
a. tropomyosin and c. actin
How many ATP molecules does aerobic respiration produce? A. 12 B. 36 C. 2 D. 40
b. 3
Which of the following muscle cell structures is the longest? A. A myofilament B. A myofibril C. A sarcomere D. A troponin molecule
b. a myofibril
Which of the following muscles is NOT named after its location in the body? A. Latissimus dorsi B. Adductor longus C. Rectus femoris D. Biceps brachii
b. adductor longus (named after its action and size)
How many ATP molecules does anaerobic respiration produce? A. 12 B. 36 C. 2 D. 40
c. 2
What is a "sarcomere"? A. A cancer of connective tissue B. The cytoplasm of a muscle cell C. A section of a myofilament D. The plasma membrane of a muscle cell
c. a section of a myofilament
Which protein(s) are found in thin myofilaments? A. Actin B. Actin and tropomyosin C. Actin, tropomyosin and troponin D. Actin, myosin, tropomyosin and troponin
c. actin, tropomyosin, and troponin
By which term is a muscle that opposes or reverses a particular movement called? A. Agonist B. Synergist C. Antagonist D. Fixator
c. antagonist
What is the substance that binds to troponin in order to cause muscle contraction? A. PO₄²⁻ B. H₃O+ C. Ca++ D. Fe++
c. ca++
What causes the myosin binding site of an actin molecule to be exposed? A. ATP attaching to the myosin cross-bridge B. A nerve impulse reaching the motor end plate of a motor nerve C. Calcium ions attaching to troponin D. Acetylcholine crossing the neuromuscular junction
c. calcium ions attaching to troponin
Skeletal muscle cells have all of the following characteristics EXCEPT one. Which one? A. A neuromuscular junction crossed by ACh (acetyl choline) B. Invaginations of sarcolemma called "T tubules" C. They are branched D. They are striated
c. they are branched
Patients confined to bed and those with plaster casts immobilising a bone frac- ture suffer muscle wasting. What is the term used for this condition? A. Disuse atrophy B. Denervation atrophy C. Muscle dystrophy D. Muscle hypertrophy
a. disuse atrophy
What structures attach a muscle to a bone? A. A tendon B. A fasciculus C. A sarcomere D. An internal intercostal
a. a tendon
What is the neurotransmitter that crosses the neuromuscular junction? A. Acetylcholine (ACh) B. Adrenalin (epinephrine) C. Noradrenalin (norepinephrine) D. Ca++
a. acetylcholine
Which of the muscles listed below is named according to its action? A. Adductor longus B. Temporalis C. Sternocleidomastoid D. Peroneus longus
a. adductor longus
Select the one INCORRECT statement about skeletal muscles A. An "agonist" opposes or reverses a particular movement. B. A muscle's attachment point to a stationary bone is called its "origin". C. A skeletal muscle cell is a "syncytium". D. Muscles that immobilise a bone are called "fixators".
a. an "agonist" opposes or reverses a particular movement
What is the role of calcium ions in muscle contraction? To: A. Bind to troponin, thus changing its shape and pulling it away from the actin molecule B. Cause the myosin cross-bridge to detach from its binding site C. Cause the action potential to propagate along the sarcolemma D. Bind with ADP during aerobic respiration to produce ATP to provide energy
a. bind to troponin, thus changing its shape and pulling it away from the actin molecule
What is the role of Ca++ in the contraction of a muscle cell? A. Ca++ binds to troponin to change its shape which reveals actin's binding site. B. Ca++ attaches to the binding site of actin. C. Ca++ detaches from ATP as it forms ADP. D. Ca++ causes the myosin head to detach from the binding site of actin.
a. ca++ binds to troponin to change its shape which reveals actin's binding site
Which statement below best describes the role of Ca++ in muscle contraction? A. Ca++ binds to troponin, thereby changing its shape to expose the binding site. B. Ca++ causes ADP and inorganic phosphate to detach from the myosin cross-bridge. C. Ca++ attaches to the myosin head, causing it to disengage from its binding site. D. Ca++ crosses the sarcolemma from the axon terminal which allows the action potential to propagate along the sarcolemma.
a. ca++ binds to troponin, thereby changing its shape to expose the binding site
Which of the following muscles is a common intramuscular injection site? A. Deltoid B. Gluteus maximus C. Vastus medialis D. Latissimus dorsi
a. deltoid (located at the upper arm at the shoulder)
Which of the following muscles is NOT named after its location in the body? A. Deltoid B. Extensor carpi ulnaris C. Rectus abdominis D. Biceps femoris
a. deltoid (named after its shape--a delta aka Greek letter triangle thing)
What is true about the energy released from glucose respiration? A. Anaerobic respiration releases more than aerobic respiration. B. Aerobic respiration releases more than anaerobic respiration. C. Aerobic and anaerobic respiration release about the same amount. D. Anaerobic respiration releases no energy.
b. aerobic respiration releases more than anaerobic respiration
Which one of the following is NOT a characteristic of skeletal muscle? A. Excitability B. Autonomic innervation C. Contractility D. Extensibility
b. autonomic innervation
Which muscle is one of the "hamstrings" group? A. Biceps brachii B. Biceps femoris C. Triceps brachii D. Quadriceps femoris
b. biceps femoris
What is the role of Ca++ in muscle contraction? A. Ca causes an action potential to travel along the sarcolemma. B. Ca binds to troponin changing its shape. C. Ca attaches to the binding site of myosin, energising it. D. Ca engages with the binding site of actin causing the power stroke.
b. ca binds to troponin changing its shape
Which of the following muscles causes the wrist to bend? A. Extensor digitorum B. Extensor carpi ulnaris C. Flexor digitorum profundus D. Abductor pollicis longus
b. extensor carpi ulnaris
Which of the following muscle structures is the largest? A. Sarcomere B. Fascicle C. Myofibril D. Muscle fibre
b. fascicle
Which of the following muscles is named using the criterion of its size? A. Sternocleidomastoid B. Gluteus medius C. Flexor digitorum profundus D. Trapezius
b. gluteus medius
Which list is in the correct order of DECREASING size? A. Muscle fibre, sarcomere, myofilament, myofibril B. Muscle, fasciculus, muscle fibre, myofibril C. Sarcomere, fasciculus, myofibril, myofilament D. Muscle, muscle fibre, myosin, myofibril
b. muscle, fascicles, muscle fibre, myofibril
What is the protein of thick myofilaments in a skeletal muscle cell? A. Tropomyosin B. Myosin C. Actin D. Acetylcholine
b. myosin
Which molecule in a muscle cell has a cross-bridge that attaches to a binding site to effect the shortening of the cell? A. Tropomyosin B. Myosin C. Actin D. Troponin
b. myosin
What are the muscles known as triceps brachii, biceps femoris and quadriceps femoris named according to? Their: A. Relative size and location of muscle's origin B. Number of origins and location in the body C. Shape of muscle and direction of muscle fibres D. Number of insertions and location in the body
b. number of origins and location in the body
What does aerobic respiration refer to? A. Glycolysis in the cytoplasm in the absence of oxygen B. Oxidative phosphorylation in the mitochondria in the presence of oxygen C. Glycolysis in the liver in the presence of oxygen D. Gluconeogenesis in the liver in the absence of oxygen
b. oxidative phosphorylation in the mitochondria in the presence of oxygen
Which one of the following is not made of skeletal muscle? A. The diaphragm B. Pyloric sphincter C. Vastus lateralis D. The tongue
b. pyloric sphincter
Which term is given to the unit of a myofibril that contracts? A. Sarcoplasm B. Sarcomere C. Sarcolemma D. Sarcoplasmic reticulum
b. sarcomere
Which of the following muscles is NOT named after its location in the body? A. Biceps brachii B. Sternocleidomastoid C. Rectus abdominis D. Flexor carpi radialis
b. sternocleidomastoid (named after its origins and insertion)
Which of these events is necessary for the contraction of a muscle cell? A. The shortening of myosin molecules B. The hydrolysis of ATP to ADP and HPO₄²⁻ in the myosin cross-bridge C. Ca2+ binding to tropomyosin causing it to change shape D. The movement of Ca2+ from the sarcoplasm into the sarcoplasmic reticulum
b. the hydrolysis of ATP to ADP and HPO42- in the myosin cross-bridge
To what does the term "endomysium" refer? A. The protein of thick myofilaments B. The tissue that surrounds a muscle fibre C. The gap between the axon terminal of a motor nerve cell and a motor endplate of a muscle cell D. The vessel from which Ca2+ ions are released prior to a muscle cell contraction
b. the tissue that surrounds a muscle fibre
Where are the semimembranosus and semitendinosus muscles located? In the: A. Seminal vesicle B. Thigh C. Forearm D. Back
b. thigh
Which statement about thick or thin myofilaments is CORRECT? A. Thick myofilaments contain the three proteins myosin, tropomyosin and troponin. B. Thin myofilaments contain the three proteins actin, tropomyosin and troponin. C. Thick myofilaments contain about 300 myosin molecules, each of which has a binding site for a cross-bridge. D. Thin myofilaments contain about 300 myosin molecules, each of which has a cross-bridge.
b. thin myofilaments contain the three proteins actin, tropomyosin, and troponin
Which of the following muscles IS named after its location in the body? A. Sartorius B. Triceps brachii C. Soleus D. Trapezius
b. triceps brachii (bracii = location on arm)
Of the events that lead to myofilaments sliding over each other, which of the following happens first? A. The myosin head engages with the binding site on actin. B. Troponin changes shape and pulls on tropomyosin. C. Calcium ions enter the cell cytoplasm. D. ATP is hydrolysed to ADP and inorganic phosphate.
c. calcium ions enter the cell cytoplasm
Which of the following groupings of muscle type and their characteristics is INCORRECT? A. Skeletal, striated, voluntary B. Smooth, visceral, involuntary C. Cardiac, striated, voluntary D. Skeletal, striated, syncytium
c. cardiac, striated, voluntary (cardiac muscle is not voluntary)
Which of these events is necessary for the contraction of a muscle cell? A. The shortening of myofilaments B. The conversion of ADP and HPO₄²⁻ to ATP in the cross-bridge C. Ca²+ binding to troponin causing it to change shape D. The movement of ACh from the sarcolemma to the axon terminal
c. ca²+ binding to troponin causing it to change shape
Which muscle is located on the posterior part of the forearm? A. Flexor digitorum superficialis B. Flexor digitorum profundus C. Extensor digitorum D. Triceps brachii
c. extensor digitorum
Which is the correct equation for anaerobic respiration in humans? A. Glucose + lactic acid → carbon dioxide + water B. Glucose → lactic acid + carbon dioxide C. Glucose → lactic acid +(little energy) D. Glucose→ lactic acid
c. glucose → lactic acid +(little energy)
Which of the following is NOT a common intramuscular injection site? A. Gluteus medius B. Deltoid C. Gluteus maximus D. Vastus lateralis
c. gluteus maximus
What is a sarcomere? A. It is the plasma membrane of a muscle cell. B. It is the cytoplasm of a muscle cell. C. It is a section of myofibril. D. It is a bundle of thick and thin myofilaments.
c. it is a section of myofibril
What characteristic of a smooth muscle cell distinguishes it from cardiac and from skeletal muscle? A. Being branched B. Being under involuntary control C. Lack of striations D. Being uninucleate
c. lack of striations
By what name is something that attaches a bone to another bone known? A. Aponeurosis B. Sarcomere C. Ligament D. Tendon
c. ligament
One muscle below is NOT named after its shape. Which one? A. Deltoid B. Rhomboid C. Masseter D. Trapezius
c. masseter
Which of the listed muscles is named according to its action? A. Rectus abdominis B. Peroneus longus C. Pronator teres D. Latissimus dorsi
c. pronator teres
Which of the following muscles is NOT a flexor of the knee? A. Semimembranosus B. Semitendinosus C. Rectus femoris D. Biceps femoris
c. rectus femoris
The part of a skeletal muscle cell that is able to contract is called A. Sarcoplasm B. Sarcolemma C. Sarcomere D. Sarcoplasmic reticulum
c. sarcomere
What is the cytoplasm of a skeletal muscle cell called? A. Sarcolemma B. Sarcomere C. Sarcoplasm D. Fasciculus
c. sarcoplasm
The muscles involved in mastication include which of the following? A. Sternocleidomastoid, scalene B. Sartorius, gracilis, soleus C. Temporalis, masseter, buccinator D. Orbicularis oculi, mentalis
c. temporalis, masseter, buccinator
With respect to the flexion of the forearm, which of the following statements is correct? A. The origin of the biceps brachii is on the radius and its insertion is on the scapula. B. The origin of the biceps brachii is on the ulna and its insertion is on the scapula. C. The agonist muscle is the biceps brachii and the antagonist is the triceps brachii. D. The agonist muscle is the biceps brachii and the antagonist is the brachialis.
c. the agonist muscle is the biceps brachii and the antagonist is the triceps brachii
Which event causes the thick filament to slide over the thin filament (i.e. the "power stroke") during muscle contraction? A. The attachment of Ca ions to troponin B. The hydrolysis of ATP to ADP, inorganic phosphate and energy C. The engagement of the head of the myosin cross-bridge with its binding site on actin D. The attachment of a molecule of ATP to the head of myosin's cross-bridge
c. the engagement of the head of the myosin cross-bridge with its binding site on actin
What does the term "origin" refer to in the musculoskeletal system? A. The point of attachment of a muscle to the "moveable" bone B. The line that separates the shaft from the end of a long bone C. The point of attachment of a muscle to the "stationary" bone D. The end of a long bone
c. the point of attachment of a muscle to the "stationary" bone
The neurotransmitter that causes an action potential to occur in a muscle cell membrane is called: A. Inorganic phosphate (HPO₄²⁻) B. Adenosine diphosphate (ADP) C. Calcium (Ca++) D. Acetylcholine (ACh)
d. acetylcholine
Which is a neurotransmitter? A. Tropomyosin B. Myosin C. Actin D. Acetylcholine
d. acetylcholine
What is the source of the majority of the energy needed by muscles for physical activity that continues for longer than 30 or 40 min? A. ATP stored in muscle fibres B. Glycolysis of glucose in the cell cytoplasm C. ATP produced from creatine phosphate stored in muscle fibres D. Aerobic respiration of pyruvic acid in mitochondria
d. aerobic respiration of pyretic acid in mitochondria
Which pair of terms below refers to a contraction and relaxation? A. Flexor and extensor B. Origin and insertion C. Brachialis and radialis D. Agonist and antagonist
d. agonist and antagonist
The energy for muscle contraction is derived from the mechanisms below EXCEPT for one. Which one is NOT a method of producing ATP? A. Anaerobic glycolysis B. Aerobic respiration C. Direct phosphorylation of ADP by creatinine phosphate D. Anaerobic digestion of lactic acid
d. anaerobic digestion of lactic acid
Which of the events below is the FIRST to occur prior to a muscle cell contracting? A. ATP binds to myosin. B. ADP detaches from myosin. C. The active site on actin is exposed. D. Ca++ is released from the sarcoplasmic reticulum.
d. ca++ is released from the sarcoplasmic reticulum
What is the source of the ATP used by muscles for vigorous activity that may last for 10-15 seconds? A. Glycolysis of glucose in the cell cytoplasm forms ATP. B. The ATP that is stored in muscle cells as ATP. C. Aerobic respiration in the mitochondria produces the ATP. D. Creatinine phosphate in muscle and ADP reacts to form the required ATP.
d. creatinine phosphate in muscle and ADP reacts to form the required ATP
One of the following muscle names refers to a superficial muscle that lies between the ribs. Which one is it? A. Serratus anterior B. Rectus femoris C. Extensor carpi radialis brevis D. External intercostals
d. external intercostals (costa means rib)
Which is the correct equation for aerobic respiration in humans? A. Glucose + oxygen → carbon dioxide + water B. Glucose + oxygen → carbon dioxide C. Glucose → carbon dioxide + water + energy D. Glucose + oxygen → carbon dioxide + water +energy
d. glucose + oxygen → carbon dioxide + water + energy
What action does the flexor carpi ulnaris perform? A. It flexes the lower arm. B. The same as the extensor carpi ulnaris. C. It flexes the fingers. D. It flexes the wrist.
d. it flexes the wrist
Which muscle naming criteria are used to name the quadriceps femoris? A. Muscle action and location B. The origin and insertion C. Location and direction of muscle fibres D. Location and number of origins
d. location and number of origins
The muscle known as the "transversus abdominis" is named according to: A. Its size and number of origins B. The direction of its muscle fibres and its action C. Its action and its location in the body D. Location in the body and direction of muscle fibres
d. location in the body and direction of muscle fibres
A feature of skeletal muscle that is NOT shared with cardiac or smooth muscle is: A. Striations B. Branched cells C. Intercalated discs D. Many nuclei
d. many nuclei
Which list is in the correct order of INCREASING size? A. Muscle fibre, sarcomere, myofilament, myofibril B. Muscle, fasciculus, muscle fibre, myofibril C. Sarcomere, fasciculus, myofibril, myofilament D. myofibril, muscle fibre, fascicles, muscle
d. myofibril, muscle fibre, fascicles, muscle
On which molecule is the energized cross-bridge which produces muscle cell contraction located? A. Fibrin B. Troponin C. Actin D. Myosin
d. myosin
Smooth muscle cells may be described by which of the following? A. Striated, voluntary, multinucleate B. Not striated, voluntary, multinucleate C. Striated, involuntary, uninucleate D. Not striated, involuntary, uninucleate
d. not striated, involuntary, uninucleate
What is the name given to the membrane that surrounds a muscle fascicle? A. Pericardium B. Peritoneum C. Periosteum D. Perimysium
d. perimysium
By what name is the plasma membrane of a muscle cell known? A. Sarcoplasm B. Sarcomere C. Sarcoplasmic reticulum D. Sarcolemma
d. sarcolemma
Microscopically, muscle fibres contain parallel myofibrils. What are the units joined end to end within a myofibril called? A: A. Myofilament B. Motor unit C. Myosin D. Sarcomere
d. sarcomere
Which of the following muscles is named after its origin and insertion points? A. Tibialis anterior B. Extensor digitorum longus C. Rectus femoris D. Sternocleidomastoid
d. sternocleidomastoid
Skeletal muscle cells can be characterised as: A. Unstriated, involuntary, multinucleate B. Unstriated, voluntary, multinucleate C. Striated, voluntary, uninucleate D. Striated, voluntary, multinucleate
d. striated, voluntary, multinucleate
When a muscle contracts, exactly what structure gets shorter? A. The fascicles of a muscle B. The myosin molecules of a myofilament C. The actin molecules of a myofilament D. The sarcomeres of a myofibril
d. the sarcomeres of a myofibril
