Anatomy and Physiology Unit 8 Quiz (Muscular System)

In a diagram where's the effort?

The point at which the muscle moves the load

What represents a second class lever?

Where the arrangement is (Effort, Load, Fulcrum)

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

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

The muscles that serves as the "prime mover" during a movement is called the...

Agonist

The different types of muscle tissue differ from each other by...

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

Myofibrils contain...

All of these, contractile, regulatory, and structural proteins

Which of the following regions of the sarcomere contain thick filaments?

All of these, zone of overlap, A band, H zone

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

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

Hyperplasia is...

An increase in the number of muscle fibers

Where is the masseter on the later view of the head?

Anterior to the ear

Where is the buccinator on the later view of the head?

Anterior to the masseter (deep)

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

Aponeurosis

Where is the orbicularis oculi on the later view of the head?

Around the eye

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

Which of the following regions of a sarcomere contain thin filaments?

Both I band and A band

Where is the longissimus cervicis?

Bottom of the triangular muscle on the neck

The sarcoplasmic reticulum is skeletal muscle fibers is used for storing...

C a 2 + (Ca2+)

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

One artery and one or two veins

The attachment of a muscle's tendon to the stationary bone is called _____; the attachment of the muscle's other tendon to the movable bone is called the ____.

Origin; insertion

What is NOT a common arrangement of muscle fascicles?

Oval

Where is the depressor anguli oris on the later view of the head?

Posterior to the mentalis

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

Production of vitamins

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

Progressive degeneration of muscles

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

Cardiac muscle

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

Cramp

Where is the zygomaticus major on the later view of the head?

Crosses the masseter inferiorly

Where is the infraspinatus?

Deep muscle inferior part of the shoulder

Where is the supraspinatus?

Deep muscle superior part of the shoulder

Where is the extensor carpi ulnaris on the posterior view of the body?

Distal medial part of the arm

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

Where is the masseter on the anterior view of the body?

In the cheek

Where is the coracobrachialis?

In the medial part of the upper arm (armpit area)

Where is the latissimus dorsi anteriorly?

In the small of the armpit

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

Increase in diameter of muscle fibers

Where is the Rhomboid major?

Inferior attachment to the spine

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

Intercalated discs

Most muscles cross at least one...

Joint

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

Lactic acid is continually produced

Where is the latissimus dorsi?

Large muscle across the back

Where is the splenius capitis?

Large muscle across the back of the neck

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

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

M line

Where is the gastrocnemius on the anterior view of the body?

Medial part of the lower leg

Where is the leveator scaplulae?

Most lateral protrusion on the neck

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 ____ on the thick filaments binds to _____ 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

Identify the highlighted muscle. It is the frontal belly of:

Occipitofrontalis

Where is the external oblique on the posterior view of the body?

On the Lateral side of the trunk

Where is the deltoid on the anterior view of the body?

On the forearm

Where is the rectus femoris on the anterior view of the body?

On the front of the thigh

Where is the soleus on the posterior view of the body?

On the lateral and medial sides of the bottom of the leg

Where is the thenar on the anterior view of the body?

On the palm of the hand

Which of the regions of a sarcomere contain titin?

From M line to Z disc

This is the least powerful type of skeletal muscle fiber.

Slow oxidative fiber

Where is the flexor carpi radialis?

The large long muscle in the middle of the arm

Where is the brachioradialis?

The lateral muscle of the arm

In a diagram the fulcrum would be where?

The leverage point (elbow)

This type of muscle works by stabilizing the origin of the agonist so that it can act more efficiently.

Fixator

Smooth muscle tone is maintained by the prolonged presence of ____ 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 proteins is used to reinforce the sarcolemma and to help transmit the tension generated by the sarcomeres to the tendons?

Dystrophin

A lever is acted at two different points by two different forces which are called the...

Effort and load

Motion will occur in a muscle when the ____ supplied exceeds the _____.

Effort; load

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

Elasticity

Which event does not occur during the onset of rigor mortis?

Enzymes from lysosomes digest crossbridges

This 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

Where is the rhomboid minor?

First muscle that inferiorly crosses the splenius capitis

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

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

Refractory period

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

To stimulate skeletal muscle contraction, acetylcholine must cross the ____ 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 is NOT a characteristic commonly used to name skeletal muscles?

Thickness of fibers

This type of fascicle arrangement has the fascicles spread over a broad area and converges at a thick central tendon.

Triangular

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

Tropomyosin and troponin