Human A&P Chapter 9

The functional connection between a neuron and a skeletal muscle fiber is a dendrite neuroma myoma synapse fascia

synapse

Tawanda finishes a sprint and suffers great pain in her calf muscles. Her muscle cramps are most likely due to a temporary deficit of actin. endorphins. ATP. ADP. myosin.

ATP

__________ degrades acetylcholine, keeping it from accumulating in the synapse. Actinase DNase Acetylcholinesterase Myosinase ATPase

Acetylcholinesterase

Which of the following is not a muscle of mastication? Medial and lateral pterygoid Mandibular All of the above Masseter Temporalis

Mandibular

Which of the following is not true? Red fibers contain more myoglobin than white. Red fibers have fewer mitochondria than white. Red roosters have red fibers and white chickens have white fibers. Red fibers contract more slowly than white. Red fibers fatigue more slowly than white.

Red fibers have fewer mitochondria than white.

The linea alba is a band of tough connective tissue to which abdominal wall muscles attach. a muscle beneath the skull. a curved, broad muscle on the side of the chest. a muscle extending from the ischial spine to the coccyx and sacrum. a muscle attached to the symphysis pubis.

a band of tough connective tissue to which abdominal wall muscles attach.

A motor unit is many myofibrils in a sarcolemma. a type of recreational vehicle. many motor end plates at a neuromuscular junction. a motor neuron and the muscle fibers connected to it. the functional unit of a muscle fiber.

a motor neuron and the muscle fibers connected to it.

People with myasthenia gravis lack dystrophin. about two-thirds of the normal number of acetylcholine receptors sarcomeres. titin. troponin.

about two-thirds of the normal number of acetylcholine receptors

The first event in muscle fiber contraction is that acetylcholine diffuses across a gap at a neuromuscular junction. morphine is released from the end of the motor neuron. calcium ions diffuse from sarcoplasmic reticulum into the sarcoplasm and bind to troponin molecules. the muscle fiber membrane is stimulated and a muscle impulse travels deep into the fiber through transverse tubules. acetylcholine is released from the end of the motor neuron.

acetylcholine is released from the end of the motor neuron.

Myofibrils are composed primarily of troponin and tropomyosin. perimysium and endomysium actin and myosin. fascia and tendons. ATP and ADP.

actin and myosin

Cardiac muscle all of the above. excites itself. responds in an all-or-none manner. is only in the heart. contracts as a syncytium.

all of the above

Functions of muscles are for muscle tone. all of the above. the heartbeat. moving bones. distribution of heat.

all of the above

The soleus is a muscle that forms part of the thigh. buttocks. shoulder. calf. abdomen.

calf.

Smooth muscle has ___________ and not troponin. acetylcholine titin norepinephrine fibronectin calmodulin

calmodulin

The buccinator muscle is in the buttocks. chest. ankle. bladder. cheek.

cheek.

Compared to skeletal muscle, smooth muscle contracts more slowly and relaxes more slowly. contracts more rapidly and relaxes more slowly. contracts more slowly and relaxes more rapidly. contracts more rapidly and relaxes more rapidly. contracts and relaxes at about the same rate.

contracts more slowly and relaxes more slowly.

The muscle that adducts and flexes the arm is the levator scapulae. teres major. none of the above. coracobrachialis. pectoralis minor.

coracobrachialis.

A tendon is ______, whereas an aponeurosis is ______. a broad, fibrous sheet of connective tissue that connects muscles to muscles; cordlike and connects bones to bones found in humans; found in apes. cordlike and connects muscles to bones; a broad, fibrous sheet of connective tissue that connects muscles to muscles none of the above cordlike and connects bones to bones; a broad, fibrous sheet of connective tissue that connects muscles to muscles

cordlike and connects muscles to bones; a broad, fibrous sheet of connective tissue that connects muscles to muscles

The relationship between ATP and creatine phosphate is that they are the same. both having three phosphate groups. both are required to stimulate a muscle to contract. creatine phosphate supplies energy to regenerate ATP from ADP and phosphate. ATP supplies energy to synthesize creatine phosphate from creatine and phosphate.

creatine phosphate supplies energy to regenerate ATP from ADP and phosphate.

The outermost layer of connective tissue surrounding a skeletal muscle is the epimysium. endomysium. myomysium. perimysium. sarcomysium.

epimysium.

A gluteal gait, in which a person walks with a waddling limp, is usually caused by a disorder of the gluteus maximus and gluteus minimus. none of the above. gluteus medius and gluteus minimus. gluteus gluteus and gluteus transverses. gluteus maximus and gluteus medius.

gluteus medius and gluteus minimus.

The movable end of a muscle is its fulcrum. twitch. source. origin. insertion.

insertion

The structures that connect cardiac muscle cells are neuromuscular discs. herniated discs. neuromuscular junctions. desmosomes. intercalated discs.

intercalated discs.

A plank position is part of a yoga/Pilates workout. The person supports the body on the floor in a prone position with the arms and feet supporting the body. It is a little like the "up" position of a push-up, held for 30 to 60 seconds. Contraction of the abdominal muscles in a plank is most likely isotopic. plurimetric. eccentric. isometric. isotonic.

isometric.

In a recording of a muscle twitch, the delay between the time a stimulus is applied and the time the muscle responds is called the latent period. stimulus period. contraction period. refractory period. relaxation period.

latent period.

Bones and muscles function as mechanical devices called monkey bars. levers. syncytia. ladders. lifts.

levers

Fibers of muscles whose motor neurons are severed all of the above. may be replaced by fat or fibrous connective tissue. hypertrophy. cannot ever be reinnervated. die.

may be replaced by fat or fibrous connective tissue.

Threshold stimulus is the none of the above. amount of acetylcholine required to contract a muscle. maximum stimulus to contract a muscle. minimal amount of energy required to contract a muscle fiber. maximum stimulus required to contract a muscle.

minimal amount of energy required to contract a muscle fiber.

Neurotransmitters are stored in vesicles in myofibrils. motor units. sarcomeres motor end plates. motor neuron endings.

motor neuron endings.

Weightlifting, in which a muscle exerts more than 75% of its maximum tension, stimulates an increase in slow, fatigable white fibers. conversion of skeletal to smooth muscle. shrinking of skeletal muscle. muscle fibers developing new filaments of actin and myosin. conversion of smooth to skeletal muscle.

muscle fibers developing new filaments of actin and myosin.

An example of a partial but sustained contraction is knee jerking. muscle tone. a titanic contraction. a twitch. eye blinking.

muscle tone.

In muscle contraction ATP supplies energy for glycogen synthesis. myofilament movement. cellular respiration. enzyme activity. creatine phosphate synthesis.

myofilament movement.

At a neuromuscular junction actin and myosin filaments slide past one another. intercalated discs are synthesized. neurotransmitters are released. neurotransmitters are synthesized. troponin and tropomyosin exchange places.

neurotransmitters are released.

Athletes usually experience muscle fatigue less quickly than nonathletes because they make more efficient use of ATP. convert glucose to lactic acid. produce less lactic acid. do not care about fatigue or pain. tolerate high concentrations of carbon dioxide.

produce less lactic acid.

The very brief moment following stimulation when a muscle remains unresponsive to additional stimulation is called the relaxation period. refractory period. latent period. refractory index. contraction period.

refractory period.

The discoloration and swelling of a muscle strain is due to torn ligaments ruptured blood vessels. separated tendons. severed nerves. excess myofibrils.

ruptured blood vessels.

The striated appearance of skeletal muscle results from the distribution of mitochondria. sarcoplasmic reticulum network. cisternae placement. sarcomere organization. transverse tubule pattern.

sarcomere organization.

Muscle fibers are basically a collection of muscles. alpha and beta subunits. synapses. connective tissue fibers. sarcomeres.

sarcomeres.

Transverse tubules and sarcoplasmic reticulum are well developed in skeletal muscle fibers. cardiac muscle fibers. smooth muscle fibers. motor neurons. nervous muscle fibers.

skeletal muscle fibers.

Both acetylcholine and norepinephrine can affect smooth muscle contraction. skeletal muscle contraction. percentage of different twitch types. exercise tolerance. synthesis of actin and myosin.

smooth muscle contraction.

Short muscle cells with centrally located nuclei are smooth muscle fibers. cardiac muscle fibers. motor neurons. skeletal muscle fibers. adipocytes.

smooth muscle fibers.

The type of muscle cell that lacks transverse tubules, has a single nucleus, and is under involuntary control is skeletal muscle. exercised muscle. cardiac muscle. smooth muscle. striated muscle.

smooth muscle.

creatine phosphate supplies energy for the synthesis of ATP. decomposes ADP. binds to Ach receptors. supplies energy for the breakdown of ATP to ADP. decomposes ATP.

supplies energy for the synthesis of ATP.

The triangle of auscultation, commonly used to hear sounds of respiratory organs, is located near the border of the gluteus maximus and gluteus minimus. pectoralis major and pectoralis minor. latissimus dorsi and serratus anterior. trapezius and latissimus dorsi. pectoralis major and serratus anterior.

trapezius and latissimus dorsi.

Arrange the following steps for contraction in the correct sequence. 1. The muscle impulse reaches the sarcoplasmic reticulum and calcium is released. 2. Thin filaments are pulled over the thick filaments. 3. Calcium floods the sarcoplasm and binds to troponin molecules leaving active sites. 4. The impulse arrives at the synapse and travels through the transverse tubules. 5. The muscle fiber shortens and contracts. 6. Tropomyosin molecules bind to exposed active sites, linking actin and myosin 4, 1, 3, 6, 2, 5 2, 5, 3, 1, 4, 6 3, 5, 2, 1, 6, 4 4, 2, 6, 5, 3, 1 6, 3, 1, 4, 2, 5

4, 1, 3, 6, 2, 5

Which of the following statements is correct? Cross-bridges form between actin and sarcolemma filaments. Myosin and actin alternate to form filaments. Actin filaments slide along myosin filaments. Tropomyosin molecules move and expose specific sites on myosin filaments. Filaments of troponin and tropomyosin slide past one another.

Actin filaments slide along myosin filaments.

A myogram is a measurement of muscle tone. a depiction of the results of a stress test. a chart that shows how many muscle cells a neuron synapses with. an instrument that detects the pattern in which neurons contact muscles. a recording of the events of a twitch.

a recording of the events of a twitch.

Muscle atrophy that progresses with aging is caused by reduction in creatine phosphate. all of the above. myoglobin. the sizes of muscle fibers. ATP.

all of the above.

Temporomandibular joint (TMJ) syndrome causes backache. all of the above. clicking sound from the jaw. insomnia. ringing in the ears.

all of the above.

Myasthenia gravis is the result of injury. a bacterial infection. a muscle in the lower limb. an autoimmune disorder. a form of cancer.

an autoimmune disorder.

A shift in metabolism that breaks down pyruvic acid to lactic acid is called glycolysis pyruvic acidosis. aerobic threshold. glycogenic threshold. anaerobic threshold.

anaerobic threshold.

The enzyme acetylecholinesterase causes acetylcholine to be secreted from the motor end plate. none of the above. bond to actin. decompose. form cross-bridges.

decompose.

Rigor mortis affects skeletal muscles a few hours after death, due to none of the above. increased ATP and decreased permeability to calcium. decreased ATP and increased permeability to calcium. nerve impulses that contract the muscles excessively. increased ATP.

decreased ATP and increased permeability to calcium.

A sign of aging of the muscular system is all of the above. decreased supplies of myoglobin to muscles. expansion of muscle fiber diameters. fewer red fibers. excess ATP.

decreased supplies of myoglobin to muscles.

The amount of oxygen liver cells require to react lactic acid to produce glucose or the glycogen glycogen is the oxygen debt. aerobic conversion. refractory quantity. lactate debt. anaerobic concentration.

oxygen debt.

Which of the following is unique in that its insertion is to fascia and not bone? palmaris longus none of the above. extensor digitorum flexor digitorum profundus extensor carpi ulnaris

palmaris longus

The toxin that causes botulism binds to acetylcholine. prevents release of acetylcholine. promotes release of acetylcholine. prevents decomposition of acetylcholine. decomposes acetylcholine.

prevents release of acetylcholine.

The muscle primarily responsible for an action is the biceps. activator. origin antagonist. prime mover.

prime mover.

Regina began an exercise program six months ago, and the muscles of her upper limbs and lower limbs are more prominent. Exercise can lead to formation of new muscle by stimulating skeletal muscle cells to release IL-6, which stimulates satellite cells to divide, producing more muscle cells. stimulating synthesis of myoglobin. stimulating motor neurons to divide and innervate more muscle cells. stimulating satellite cells to release IL-6, which stimulates fibroblasts to differentiate as muscle cells. stimulating connective tissue to differentiate as muscle tissue.

stimulating skeletal muscle cells to release IL-6, which stimulates satellite cells to divide, producing more muscle cells.

A muscle that assists a prime mover is a(n) lever. synergist. none of the above. agonist. antagonist.

synergist.

Oxygen debt in muscles may develop because of too much oxygen used in forming pyruvic acid when skeletal muscles are contracted strenuously for a minute or two. too many mitochondria utilizing oxygen to synthesize ATP when skeletal muscles are contracted for a minute or two. the inability of myoglobin molecules to store enough oxygen when skeletal muscles are used strenuously for a minute or two. too high a concentration of oxygen in the atmosphere. the inability of respiratory and circulatory systems to supply enough oxygen to skeletal muscles when used strenuously for a minute or two.

the inability of respiratory and circulatory systems to supply enough oxygen to skeletal muscles when used strenuously for a minute or two.

Skeletal muscles help maintain body temperature in that excess myosin is quickly metabolized to yield heat. the more active they are, the more heat is released. the more active they are, the more heat is used up. they conserve actin and myosin in cold weather. they produce more actin and myosin in hot weather.

the more active they are, the more heat is released.

The functional unit of muscle contraction is the muscle. the sarcomere. the muscle fiber. the myosin cross-bridge. the myomere.

the sarcomere.

The severe pain of compartment syndrome is caused by damaged muscle tissue. lack of fluid in the compartment. stretched tendons. too much fluid in the compartment. tears in the compartment wall.

too much fluid in the compartment.

Transverse tubules store sodium ions for the action potential at the cell surface. store calcium ions. connect actin and myosin. transmit muscle impulses into the cell interior. transmit nerve impulses out of the muscle.

transmit muscle impulses into the cell interior.

Smooth muscle lacks gap junctions. myofibrils. nuclei and mitochondria. actin and myosin. transverse tubules and striations.

transverse tubules and striations.