Ch. 10 Muscular Tissue

Which of the following regions of the sarcomere contain thick filaments

(all of these) Zone of overlap, A band, H zone

Myofibrils contain

(all of these) contractile, regulatory, and structural proteins

Which of the following are commonly used to produce ATP during skeletal muscle contraction

(all of these) creatine phosphate, anaerobic cellular respiration, and aerobic cellular respiration

The different types of muscle tissue differ from each other by

(all of these) microscopic anatomy, location,and type of control

After prolonged strenuous exercise has stopped, heavy breathing will often continue for several minutes in order to provide the oxygen needed to

(all of these) replace oxygen displaced from muscle myoglobin, resynthesize creatine phosphate, and convert the lactic acid produced during exercise back into glycogen

In skeletal muscles, the combined amounts of creatine phosphate and ATP provide enough energy for the muscle to contract maximally for approximately

15 seconds

How much of the total body weight of an average adult is muscle tissue

40 to 50%

What energizes the myosin head

ATP hydrolysis reaction

Hyperplasia is

An increase in the number of muscle fibers

Which is a correct sequence of events in the onset of rigor mortis

Cellular membranes become leaky -> Calcium ions leak into the sarcoplasm -> myosin heads bind to actin -> muscles are in a state of rigidity

Which event does not occur during the onset of rigor mortis

Enzymes from lysosomes digest crossbridges

Which of the following statements does NOT accurately describe aerobic cellular respiration in skeletal muscles

Lactic acid is continually produced

During muscle contraction by the sliding filament mechanism, thin filaments are pulled toward the

M line

Which of the following is NOT a major function of muscle tissue

Production of vitamins

This is also referred to as the period of lost excitability in skeletal muscle fibers

Refractory period

The type of tendon formed when the connective tissue elements of a skeletal muscle extend as a broad flat layer

aponeurosis

Calcium ions are released from the sarcoplasmic reticulum into the cytosol

at the beginning of a contraction

Which of the following correctly lists the sequence of structures that action potentials must move through to excite skeletal muscle contraction

axon of neuron, sarcolemma, T tubules

Which is NOT a side-effect of anabolic steroid use by male athletes

baldness

smooth muscle tone is maintained by the prolonged presence of _(blank)_ in the muscle cell's cytosol

calcium ions

Skeletal muscle contraction will continue to occur as long as the following chemicals are available in the cytosol of the muscle fiber

calcium ions and ATP

Which of the following types of muscle tissues contracts when excited by their own autorhythmic muscle fibers

cardiac muscle

Which of the following types of abnormal contractions of skeletal muscle may be cause by holding a position for a prolonged period

cramp

Which of the following proteins is used to reinforce the sarcolemma and to help transmit the tension generated by the sarcomeres to the tendons

dystrophin

This is the property of muscle that gives it the ability to stretch without damage

elasticity

The is the outermost layer of connective tissue surrounding a skeletal muscle

epimysium

Which of the following types of abnormal contraction of skeletal muscle is caused by a twitch of an entire motor unit and is visible under the skin

fasciculation

Leg muscles are predominantly composed of this type of muscle fiber

fast glycolytic

Which of the following types of abnormal contraction of skeletal muscle is caused by a single muscle fiber, is spontaneous and is not visible under the skin

fibrillation

An EMG can be used to determine each of the following except

find the precise location of a muscle tumor

Which of the regions of a sarcomere contain titin

from M line to Z disc

A period of sustained skeletal muscle contraction in which individual twitches cannot be detected is called

fused tetanus

After the fusion of myoblast, the muscle fiber loses its ability to do what

go through cell division

Which of the following is a common characteristic of fast glycolytic (FG) skeletal muscle fibers

high amount of glycogen in the sarcoplasm

After several visits to the gym and serious "iron pumping" (strength training) you notice that your biceps have enlarged. Which one of the following has happened to your muscles

hypertrophy

The mitochondria in skeletal muscle fiber are arranged

in rows near the contractile muscle proteins

Which of the following best describes the condition known as muscular hypertrophy

increase in diameter of muscle fibers

Which of the following microscopic structures is only found in the cardiac muscle tissue

intercalated discs

During this period of a twitch contraction, the muscle action potential moves along the sarcolemma of the muscle cell and triggers calcium release into the sarcoplasm

latent period

In an isometric contraction the muscle develops tension but does not

lengthen

This consists of a somatic motor neuron and all the skeletal muscle fibers it stimulates

motor unit

Increasing the number of active motor units within a skeletal muscle is called

motor unit recruitment

Which of the following disorders is characterized by the wasting away of muscle due to the progressive loss of myofibrils

muscular atrophy

The contractile organelles of a skeletal muscle fiber are thread-like structures called

myofibrils

On which of the following proteins is the enzyme ATPase located

myosin

Which of the following functions as a motor protein in all three types of muscle tissue

myosin

Cross bridges are formed during muscle contraction when _(blank)_ on the thick filaments binds to _(blank)_ on the thin filaments

myosin; actin

A structural protein that is not associated with thin filaments and serves to anchor the thin filament to the Z-disc is called

nebulin

Myasthenia Gravis is an autoimmune disorder that targets the ACh receptors at the NMJ and ultimately reduces the number of available receptors. Predict what happens if you treat the patient with a drug that inhibits the activity of acetylcholinesterase

normal contraction

How many arteries and veins usually accompany a single nerve penetrating a skeletal muscle

one artery and one or two veins

Which of the following is not seen in exercise-induced muscle damage

progressive degeneration of muscles

In a neuromuscular junction, the effect on acetylcholine (ACh) binding to receptors on the motor end plate lasts only briefly due to

rapid destruction of A C h in the synaptic cleft by acetylcholinesterase

Which term or condition in characterized by a loss of muscle tone

rigidity

Which of the following is NOT a common side effect of creatine supplementation

rigor mortis

Which of the following types of muscle tissue is capable of undergoing the stress-relaxation response when they are stretched

single-unit smooth muscle fibers

This is the least powerful type of skeletal muscle fiber

slow oxidative fiber

To stimulate skeletal muscle contraction, acetylcholine must cross the _(blank)_ of the neuromuscular junction and bind to receptors on the motor endplate

synaptic cleft

In neuromuscular junctions, synaptic vesicles containing acetylcholine are found suspended in the cytosol of

synaptic end bulbs

Release of calcium from these structures triggers skeletal muscle contractions

terminal cisterns of sarcoplasmic reticulum

What regulatory proteins can be found in the thin filaments of skeletal muscle fibers

tropomyosin and troponin

A brief contraction of all muscle fibers in a motor unit in response to a single action potential moving down the somatic neuron is knows as

twitch contraction

The sarcoplasmic reticulum is skeletal muscle fibers is used for storing

C a 2 + (Ca2+)

Which of the following regions of a sarcomere contain thin filaments

Both I band and A band