a&p quiz 5 review
Which of the following is NOT a function of skeletal muscle?
Constriction of organs
Which of the following occurs during recovery from oxygen deficit?
Conversion of excess lactate to glucose
Some people suffer involuntary urination due to incompetence of which muscle?
External urethral sphincter
Which term below best describes the deltoid?
Extrinsic
Which muscle everts and plantar flexes the foot?
Fibularis brevis
Which of the following muscles is found in the lateral compartment of the leg?
Fibularis longus
Carpal tunnel pressure is sometimes relieved by surgically excising part or all of which structure?
Flexor retinaculum
Which of the following muscles of facial expression is not innervated by the facial nerve?
Levator palpebrae superioris
Which back muscle extends the head?
Longissimus capitis
Arrange these structures as they participate in excitation-contraction.
Sarcolemma, T tubules, sarcoplasmic reticulum, Ca2+
Which of the following is the longest muscle in the body?
Sartorius
Which muscle rotates and protracts the scapula, and elevates the ribs?
Serratus anterior
Which of the following is true concerning isotonic eccentric contraction?
The muscle lengthens, but tension remains constant.
Which of the following is true concerning isotonic concentric contraction?
The muscle shortens, but tension remains constant.
Which of the following statementsdoes not accurately describe factors that determine the amount of force generated during a muscle contraction?
The number of cross-bridges that can form is higher in a short muscle fiber compared to longer fibers.
A patient has a broken arm and must wear a cast for a prolonged period of time. Which of the following is mostly likely to be true when the cast is removed?
The patient's arm muscles will have undergone atrophy.
Which of the following is NOT a property of the myosin head?
They bind to troponin.
A volleyball player depends on the gastrocnemius muscles for plantar flexion, whereas a marathon runner depends more on the soleus muscles for the same action. What characteristic of the soleus muscles makes this so?
They make more use of aerobic respiration.
Drugs called calcium channel blockers may be used to lower blood pressure by causing arteries to vasodilate. How do you suppose these drugs work?
They prevent calcium from entering smooth muscle, thus allowing the muscle to relax.
What is the role of pacemaker cells?
They rapidly develop action potentials
Which of the following statements concerning fast-twitch muscle fibers is true?
They split ATP rapidly.
After childbirth, a woman begins experiencing tremendous pain in her groin, making it difficult for her to walk. An x-ray shows a fracture extending from her symphysis pubis to the inferior ramus of the pubis. As a result of the fracture, which group of muscles might be impaired?
Thigh adductors
Which of the following would occur as a result of a single muscle contraction?
Twitch
Which fibers are primarily responsible for producing lactate?
Type IIB fast fibers
Which of the following is a part of the quadriceps femoris muscle group?
Vastus lateralis
Well-developed mentalis muscles result in_________.
a dimple in the chin
A synergist is
a group of muscles that work together to cause movement.
An isometric contraction is described as
a muscle produces an increasing tension as the length remains constant.
An isotonic contraction is described as
a muscle produces constant tension during contraction.
A concentric contraction is described as
a muscle produces increasing tension as it shortens.
An eccentric contraction is described as
a muscle produces tension, but the length of the muscle is increasing.
An antagonist is
a muscle working in opposition to another muscle.
The gluteus maximus
accounts for a sprinter's stance.
Synaptic vesicles in the neuromuscular junction contain
acetylcholine
The active sites to which cross-bridges attach are found on the
actin myofilaments.
During the contraction phase of a muscle twitch,
actin-myosin cross-bridges form.
Tetanus of muscles is described as
action potential frequency is high enough that no relaxation of muscle fibers occurs.
A stimulus either causes an action potential or it doesn't. This is called
an all-or-none response
Smooth muscle and cardiac muscle are similar in that they both
are under involuntary control.
In humans
back muscles are strong to maintain erect posture.
Supination of the forearm and hand is accomplished by the_________.
biceps brachii and supinator
In smooth muscle, cross-bridging occurs due to
both Ca2+ binding to calmodulin and myosin kinase adding a phosphate to myosin heads.
Jason was attempting a jump shot and fell to the ground in pain, grasping at the calf of his leg. There is an enormous bulge in his leg just below the popliteal fossa, and he can't plantar flex that foot. Most likely he has injured his_________.
calcaneal tendon
When an action potential reaches the presynaptic terminal,
calcium ions diffuse into the presynaptic terminal through voltage-gated ion channels.
Treppe
can contribute to improved muscle efficiency. may be due to an increase in the level of around the myofibril. is an example of a graded response. is achieved during warm-up exercises. All of these choices are correct.
The orbicularis oculi muscle
causes crow's feet wrinkles.
If one nerve stimulus arrives at a muscle fiber so soon that the fiber does NOT relax at all from the previous twitch, the most likely result will be_________.
complete tetanus
A condition in which stimuli occur so rapidly that there are no intervening relaxations between contractions is called
complete tetanus.
T tubules
conduct action potentials deep into the muscle fiber.
A proper definition of muscle tone is
constant tension produced by muscles for long periods of time.
Muscle myofibrils
contain myosin and actin myofilaments
Actin myofilaments
contain strands of fibrous actin.
The H zone
contains only myosin myofilaments.
Lack of acetylcholinesterase in the synaptic cleft would result in
continuous stimulation of the postsynaptic membrane.
The capacity of a muscle cell to shorten forcefully is known as
contractility
If Na+ cannot enter a muscle fiber in response to a stimulus,
contraction cannot occur.
The zygomaticus major muscle
contributes to laughing and smiling
The depressor anguli oris muscle
contributes to pouting
Triangular muscles, like the pectoralis major are also called_________ muscles.
convergent
The condition of painful, spasmodic contractions of muscles is referred to as
cramps
During resting conditions,_________ is synthesized to store energy.
creatine phosphate
Sarcoplasm is the
cytoplasm of a muscle fiber.
Raising your arm to shoulder level is accomplished almost entirely by the_________.
deltoid
Smooth muscle
depolarizes when both Na+ and Ca2+ diffuse into the cell.
When someone says to "turn that frown upside down," they mean to relax your_________ and contract your_________.
depressor anguli oris; levator anguli oris
The major movement produced during quiet breathing is accomplished by the_________.
diaphragm
In order to put on a glove, the fingers are abducted by hand muscles called the_________.
dorsal interossei
In smooth muscle, most of the needed for muscle contraction
enters from extracellular fluid.
Functionally, smooth muscle
exhibits autorhythmic contractions.
Acetylcholine is released from the presynaptic terminal by the process of
exocytosis
Contracting the trapezius muscle would
extend and laterally flex the neck.
The anconeus works with the triceps brachii to_________.
extend the forearm
Inflammation of the fibrous connective tissue resulting in stiffness and soreness is
fibrositis
The teres major and teres minor are not involved in
flexion and abduction of the arm.
The radial pulse can be felt just lateral to the tendon of the_________.
flexor carpi radialis
The muscles of the anterior group of forearm muscles are primarily_________.
flexors
One ATP molecule is required for
formation of the cross-bridge, for movement of the cross-bridge, and for release of the cross-bridge.
The bulge of the calf is caused by the_________ and_________ muscles.
gastrocnemius; soleus
The biceps femoris is part of the_________.
hamstring muscles
Tetanus of a muscle is thought to be caused by
high Ca 2+ concentrations in the sarcoplasm.
The rotator cuff muscles
hold the head of the humerus in the glenoid fossa of the scapula.
Curare blocks acetylcholine receptors at the motor end plate. This would result in
inability of the muscle fiber to respond to nervous stimulation.
If one nerve stimulus arrives at a muscle fiber so soon that the fiber has only partially relaxed from the previous twitch, the most likely result will be_________.
incomplete tetanus
The training regimen of a competitive weight lifter is designed partly to
increase the average number of myofibrils per muscle fiber.
Anabolic steroids can do all of the following except
increase the number of muscle fibers.
As muscle activity increases, the body temperature_________.
increases
Intense exercise that results in a great deal of anaerobic activity
increases muscular strength and mass.
Aerobic exercise
increases vascularity of muscle. develops fatigue-resistant fast-twitch fibers. can increase the efficiency of slow-twitch fibers. can increase the number of mitochondria in muscle fibers. All of these choices are correct.
Muscles that change the shape of the tongue are called_________ muscles.
intrinsic
The electrical properties of cells are the result of
ion concentration differences across the plasma membrane.
Physiological contracture
is a condition in which cross-bridges cannot release.
Muscle tone
is a constant tension produced by muscles for long periods of time.
A fascicle
is surrounded by perimysium.
The refractory period
is the time during which the tissue cannot respond again.
Each_________ includes a Z disc and extends from each side of the Z disc to the ends of the myosin myofilaments.
isotropic band or I band
In the body's lever systems, the
joint represents the fulcrum point.
In lifting a heavy weight from the floor, one should use the power of the_________ in order to avoid straining the lower back.
knee and hip extensors
A by-product of anaerobic respiration in muscle fibers is
lactate
The time between application of the stimulus to a motor neuron and the beginning of contraction is called the_________ phase.
latent or lag
Eversion and plantar flexion is accomplished by muscles in the_________ compartment.
lateral
The arm is attached to the thorax by the_________.
latissimus dorsi and pectoralis major
The pelvic diaphragm is formed by the
levator ani and coccygeus muscles.
Athletes who train at high altitudes increase their red blood cell count, which increases their oxygen supply during exercise. Increased oxygen supply results in
longer aerobic respiration.
The length of the resting sarcomere is
longer than the length of a contracted sarcomere
Skeletal muscle develops from cells called
myoblasts
Muscle hypertrophy results from increased numbers of
myofibrils and sarcomeres.
ATPase is found in
myosin heads
At rest, the inside of the sarcolemma is_________ relative to the outside.
negatively charged
The sites where a chemical substance is transmitted from the presynaptic terminal of an axon to the postsynaptic membrane of a muscle fiber are called
neuromuscular junctions
Raising the eyebrows is the action of the_________ muscle.
occipitofrontalis
Visceral smooth muscle
occurs in sheets and exhibits numerous gap junctions
An action potential
occurs when the local potential reaches threshold level
A sarcomere extends from
one Z disk to an adjacent Z disk.
The digastric muscle is involved in_________.
opening the mouth
Closing or puckering the lips is the action of the_________ muscle.
orbicularis oris
The sternocleidomastoid muscle extends from the mastoid process of the temporal bone to the sternum and medial clavicle. When both sternocleidomastoid muscles contract, the head is flexed. The end of the muscle that connects to the sternum is the_________.
origin
The brachioradialis is named for its_________.
origin and insertion
When repolarization of the plasma membrane is complete, the
original polarity of the cell is restored.
A skeletal muscle generates the greatest tension when it is
partially stretched before being stimulated.
Muscles that have their fasciculi arranged like barbs of a feather along a common tendon are called_________.
pennate
The type of muscle that can contract with the greatest force is the_________.
pennate
When the myosin head flexes into a bend, pulling the actin filament along with it, this is called the
power stroke
A myofilament is the
protein strand composed of actin or myosin.
Flexion of the hip is a movement produced by the_________.
psoas major and iliacus
The orbicularis oris muscle
puckers the mouth for kissing.
As you are lifting a box, someone places extra weight on top of it. For your muscle to continue contracting and lifting the box, the muscle must
recruit more muscle fibers.
The abdominal muscle that has its origin at the pubic crest and symphysis pubis is the_________.
rectus abdominis
When an intramuscular injection is given in the anterior aspect of the thigh, the injection is in the_________.
rectus femoris
Myosin phosphatase
removes phosphate from myosin
Muscular dystrophy is characterized by
replacement of muscle tissue by connective tissue.
Diseases that affect the ability of skeletal muscle to contract are considered life threatening because
respiratory movements depend on skeletal muscle contractions.
Muscles exhibit the property of excitability. This means that the muscle
responds to stimulation by the nervous system.
Multiple wave summation
results in complete and incomplete tetanus.
Contracting the right sternocleidomastoid muscle would
rotate the head toward the left
The muscle that is used to cross the legs is_________.
sartorius
Maureen is hiking in the cold, and to maintain homeostasis her body begins to
shiver
Depolarization of the plasma membrane occurs when there is a rapid influx (inflow) of
sodium ions.
The sarcoplasmic reticulum
stores Ca2+
The term "shin splints" is applied to
stress fractures of the fibula 2 to 5 cm distal to the knee.
A sarcomere is the
structural and functional unit of the skeletal muscle fiber.
Endomysium is a delicate network of loose connective tissue that
surrounds each muscle fiber.
Epimysium
surrounds individual muscles.
When you "pull your tummy in" and compress your abdomen, you use the rectus abdominis, external abdominal oblique, internal abdominal oblique, and transversus abdominis muscles. This is an example of muscles working as_________.
synergists
In order for muscle relaxation to occur,
the active sites on actin must be blocked.
Oxygen deficit represents
the amount of O2 that cells need to replenish ATP supplies after exercise.
The type of muscle fatigue known as "psychological fatigue" is the result of
the emotional state of an individual.
Concentric contractions occur when
the muscle produces increasing tension as it shortens.
The prime mover is
the muscle that does most of the movement.
Increased strength of a trained muscle is due to
the nervous system's ability to recruit a large number of motor units simultaneously.
Whole muscles can respond in a graded fashion to stimuli by varying
the number of motor units recruited
Excitation-contraction coupling begins with
the production of an action potential in the sarcolemma.
Smooth muscle is regulated by all of the following except
the somatic nervous system.
The origin is
the stationary end of the muscle.
Due to the pattern of innervation of skeletal muscle, one would expect that
there are fewer motor neurons than skeletal muscle fibers.
The plasma membrane of an excitable cell is more permeable to K+ because
there are more leak ion channels for K+ than Na+.
Myosin is also known as the
thick myofilament.
The extensor pollicis brevis moves the_________.
thumb
The thenar muscles are involved in controlling the_________; the hypothenar muscles control the_________.
thumb; little finger
The muscles that laterally rotate and depress the scapula, as in shrugging and lowering the shoulders, are the_________.
trapezius and serratus anterior
If abdominal muscles are contracted while the vertebral column is fixed, this will aid in_________.
vomiting childbirth urination defecation All of the choices are correct.
Multiunit smooth muscle is located in the
wall of blood vessels.
Michael Jordan was arguably the best player in professional basketball history. Scientifically, one would expect him to have highly developed_________ fibers.
white
Aerobic respiration
yields as many as 36 ATP per glucose molecule metabolized.
Which muscle fixes the clavicle or elevates the first rib?
Subclavius
Arrange the following list of biochemical events in the correct sequence.(1) An action potential is conducted deep into the muscle fiber by the T tubule.(2) Calcium ions bind to troponin.(3) The membranes of the sarcoplasmic reticulum become more permeable to calcium ions.(4) Calcium ions diffuse into the sarcoplasm around the myofibril.(5) The troponin-tropomyosin complex moves exposing active sites.
1, 3, 4, 2, 5
List the following structures in order from smallest to largest.(1) Muscle fiber(2) Myofilament(3) Myofibril(4) Muscle fascicle
2, 3, 1, 4
What is a triad?
A T tubule and two adjacent terminal cisternae
The region of the sarcomere that contains both actin and myosin myofilaments is called the
A band.
What is tropomyosin?
A protein found along the groove of the F-actin double helix
You are hired to work in a laboratory to measure the rate of human muscle contraction. Which of the following might decrease in quantity in muscle fibers undergoing contractions?
ATP
Which of the following statements best predicts the effect of a substance that blocks creatine kinase activity?
ATP production from creatine phosphate would decrease.
Which of the following is found in the posterior group of forearm muscles?
Abductor pollicis longus
Which of the following correctly describes myoglobin's special function in muscle tissue?
Acts as a reservoir for O2
A lack of mitochondria within skeletal muscle fibers would impair which ATP-yielding chemical process?
Aerobic respiration
When skeletal muscle is producing CO2 and water while making ATP, which chemical processes could be active at this time?
Aerobic respiration
Which chemical pathway do your muscles depend on while you are watching a movie?
Aerobic respiration
What is an oxygen deficit?
After exercise, the O2 taken in that exceeds the O2 required for resting metabolism
Which metabolic pathway do skeletal muscles rely on when someone is lifting weights?
Anaerobic respiration
A male sustains a crushing injury to his foot. After weeks of care, he begins to notice that he cannot bend the little toe on his right foot. Which of the following would be a logical diagnosis?
Atrophy of the flexor digiti minimi brevis
Alexandria, a sprinter, experienced thigh pain during the start of her last race. Within 48 hours of the race, she noticed extensive bruising on the back of her thigh extending into the back of the knee and has difficulty rising from a seated position and flexing her knee. Bending at the waist generates more pain. Which muscle is likely injured?
Biceps femoris
Of the following muscles of the thigh, which one does NOT pull the leg forward?
Biceps femoris
Of the following muscles of the thigh, which one is NOT part of the quadriceps group?
Biceps femoris
Of the following muscles of the thigh, which one is on the posterior side?
Biceps femoris
Which of the following is a posterior thigh muscle?
Biceps femoris
Which of the following muscles attaches on the head of the fibula?
Biceps femoris
Damage to the muscle called the levator ani would result in
Both "difficult defecation" and "decreased support for the pelvic viscera" are correct.
Which of the following will respond to a threshold stimulus with an all-or-none contraction?
Both a single muscle fiber and a single motor unit are correct.
Which of the following statements regarding the sliding filament model is false?
Both actin and myosin myofilaments shorten during contraction.
A lack of glycolytic enzymes within skeletal muscle fibers would impair which type of ATP-yielding process?
Both anaerobic respiration and aerobic respiration are correct.
Alex is participating in a 50-meter dash. Predict the most important chemical process his muscles will rely on during this race.
Both anaerobic respiration and creatine phosphate breakdown are correct.
Which type of muscle tissue is autorhythmic?
Both cardiac and smooth muscle are correct.
Which type of muscle tissue possesses striations?
Both skeletal and cardiac muscle are correct.
Which type of muscle tissue causes contraction of the heart?
Cardiac muscle
Which type of muscle tissue has cells that branch?
Cardiac muscle
All of the following muscles are rotators of the arm. Which is a lateral rotator of the arm?
Deltoid
Which of the following conditions in muscle fibers would contribute to muscle fatigue?
Depletion of ATP reserves
Which of the following situations occurs in electrically excitable cells?
Depolarization causes voltage-gated sodium ion channels to open.
Which of these muscles helps to open the mouth?
Digastric
Which of the following connective tissue layers is outside all the others?
Epimysium
Which back muscle inserts on the ribs and vertebrae?
Erector spinae
Which muscle extends the four lateral toes?
Extensor digitorum longus
Which muscle extends the big toe?
Extensor hallicus longus
Which abdominal wall muscle is the most superficial of the oblique muscles?
External abdominal oblique
Consider the following four phrases and select the one that does not belong with the others.
Fuels runner in a marathon
Which of the following correctly lists the arrangement of components found in a third-class lever?
Fulcrum-pull-weight
Muscles can be classified based on their shape and fascicle orientation. Which shape has muscle fibers that run the length of the muscle and taper at each end?
Fusiform
Which of the following is inserted on the calcaneus by the Achilles tendon?
Gastrocnemius
Which of the following muscles is used when walking on your tiptoes?
Gastrocnemius
When you say "ah" and stick out your tongue, which muscle do you use?
Genioglossus
Which of the following would be caused by a contraction of smooth muscle?
Goose bumps
Which of the following represents a class I lever system?
Hyperextension of the head
Which of the following statements concerning types of muscle contractions is false?
In isometric contractions, the amount of tension produced by the muscle is constant.
Which of the following is NOT a known effect of illegal use of anabolic steroids in large dosages?
Increased cardiovascular fitness
Which of the following helps explain the increased tension seen in multiple wave summation?
Increased concentration of Ca2+ around the myofibrils
Which of the following changes would have the most dramatic effect on the membrane potential?
Increased permeability of the membrane to Na+
Select the phrase that does not belong with the others.
Increased vascularity
Which abdominal wall muscle inserts on the 10th to 12th ribs and rectus sheath?
Internal abdominal oblique
Which of the following muscles contracts during forced expiration?
Internal intercostals
Which back muscle originates on the vertebral spinous processes?
Interspinales
A toxin released by the anaerobic bacterium Clostridium botulinum causes the food-borne illness known as botulism, which inhibits the release of ACh at the neuromuscular junction. What effect does this have on a person infected with the bacterium?
It causes flaccid paralysis, and if it affects the respiratory muscles, can result in death.
Which of the following best describes the insertion of the extensor digitorum?
It indirectly inserts on all digits of the hand except the thumb.
Which of the following is NOT true of muscular atrophy?
It is irreversible.
Identify the statement concerning skeletal muscle that is true.
It is responsible for locomotion
Which of the following is true regarding the levator scapula muscle?
It laterally flexes the neck if the scapula is fixed.
Which of the following is NOT true of the latch state of smooth muscle contraction?
It occurs when the phosphate is removed while the cross-bridges are not attached to actin.
Atrophy at the neuromuscular junction that naturally occurs with age would have what effect on muscles?
It would decrease the number of action potentials sent to the muscle fiber.
Hannah has damaged her left deltoid muscle. Which of the following actions would least likely be affected by the damage?
Moving her arm medially
Which of the following actions is caused by contraction of skeletal muscle?
Moving your feet in walking
Which back muscle extends and rotates the vertebral column?
Multifidus
Which of the following is mismatched?
Myosin myofilaments - thin myofilaments
Which of the following causes an unequal ion concentration across the resting plasma membrane?
Negatively charged proteins not readily diffusing across the plasma membrane
Which of the following structures contains the other four items listed?
Neuromuscular junction
Which of the following events occurs on the postsynaptic membrane?
Neurotransmitter combines with a receptor molecule
Which of the following is true?
Optimal actin and myosin overlap will produce maximal contraction.
Which of the following muscles is involved in swallowing?
Palatopharyngeus
Which muscle acting on the arm assists in deep inspiration?
Pectoralis major
Which of the following muscles of the chest has its insertion on the humerus?
Pectoralis major
The rectus femoris is an example of which muscle shape?
Pennate
When a nurse draws blood, it is not uncommon for the needle to penetrate which muscle near the cubital region?
Pronator teres
Which muscle flexes the vertebral column?
Psoas minor
Which of the following muscles is named for its location?
Quadriceps femoris
Which type of muscle tissue is multinucleated?
Skeletal muscle
Which muscle(s) can contract without the need for nervous stimulation?
Smooth and cardiac muscle
Which type of muscle tissue causes peristalsis?
Smooth muscle
Which type of muscle tissue causes vasoconstriction?
Smooth muscle
Which type of muscle tissue has spindle-shaped cells?
Smooth muscle
Which of the following statements about muscle tissue is true?
Smooth muscle is found in the walls of hollow organs.
Which muscle plantar flexes the foot?
Soleus
Which of the following correctly states the proximal and distal attachments of the sternocleidomastoid?
Sternal manubrium and medial one-third of clavicle; mastoid process and lateral half of superior nuchal line
Choosing from the lateral neck muscles, which muscle is the prime mover for flexion of the head at the neck?
Sternocleidomastoid
Of the following muscles of the forearm, which one rotates the forearm to turn the palm upwards?
Supinator
A baseball pitcher who injures one of his SITS muscles most commonly sustains tears to the tendon of which muscle?
Supraspinatus
What would result from a lack of extracellular Ca2+ at the neuromuscular junction?
Synaptic vesicles would fail to fuse and ACh would not be released.
Which of the following statements best distinguishes between tetanus and treppe?
Tetanus occurs when stimulation of muscle occurs frequently with little to no relaxation between stimuli; treppe occurs when stimulation of muscle occurs frequently, but complete relaxation occurs between stimuli.
Myastensia gravis results from the destruction of acetylcholine receptors at the neuromuscular junction, but treatment involves medications that reduce acetylcholinesterase activity. Which statement best explains the effectiveness of these medications?
The antibodies destroy some but not all of the acetylcholine receptors, so reducing acetylcholinesterase activity increases the likelihood that acetylcholine will bind to the remaining receptors.
A cancer patient is told by their physician that their colon is lacking smooth muscle tone. What does this mean?
The colon is unable to maintain constant tension for sustained periods of time.
What is a cross-bridge?
The combination of myosin heads with active sites on actin molecules
Of the following muscles of the leg, which one is on the anterior side of the leg?
Tibialis anterior
Which muscle dorsiflexes and inverts the foot?
Tibialis anterior
Which of the following muscles is not externally visible on the trunk of the body?
Transverse abdominal
Which abdominal wall muscle inserts on the xiphoid process and the linea alba?
Transversus abdominis
Which of the following muscles is named for its shape?
Trapezius
Which of the following muscles moves the scapula?
Trapezius
