Muscle Test

Skeletal muscle accounts for at least _____% of body mass

Skeletal muscle accounts for at least _____% of body mass

40%

Which type of muscle tissue can contract rapidly, but tires easily and must rest after short periods of activity?

skeletal

Cells of which type of muscle tissue are elongated and therefore also referred to as muscle fibers?

skeletal/smooth

Which type of muscle tissue is/are found attached to the bones of the body?

skeletal only

Which of the following types of muscle tissue is/are striated?

cardiac and skeletal

Which of the following types of muscle tissue is/are voluntary?

skeletal only

The pumps that move Na + /K + , H + /K + , and Ca 2+ of skeletal muscle across cell membranes are examples of

Active transport

Which type of muscle tissue is/are found lining organs and hollow tubes/tracts of the body?

smooth only

Which of the following types of muscle tissue is/are not striated?

smooth only

Which of the following types of muscle tissue is/are involuntary?

smooth, cardiac

All of the following statements about smooth muscle are true EXCEPT

They have striations

Which type of muscle tissue is/are found only in the heart?

cardiac only

Locomotion and manipulation of the body is the result of the joint effort of the muscular system and ________ system.

skeletal

The characteristic striation of a sarcomere reflect the organization of;

actin and myosin filaments

The two main parts of the striation pattern of skeletal muscle fibers are

I bands and A bands

The striations of skeletal muscle form a repeating pattern of units called ________.

sarcomeres

Myofibrils consist of two kinds of protein filaments-thick ones composed of _______ and thin ones composed of ________.

myosin, actin

Correctly order the following structures from outermost to innermost

4, 2, 3, 1

The cytoplasm of a skeletal muscle fiber is also known as it's

sarcoplasm

The cell membrane of a skeletal muscle fiber is also known as it's

sarcolemma

Bundles of skeletal muscle fibers which are separated into compartments by perimysium, are called;

fascicles

Each muscle fiber within a fascicle lies within a layer of connective tissue in the form of a thin covering called ________.

endomysium

Which term includes the epimysium, endomysium, and perimysium

fascia

Which of the following is another layer of connective tissue which extends inward and separates the muscle tissue into small compartments?

perimysium

Which of the following is the layer of connective tissue that closely surrounds the skeletal muscle?

Epimysium

Which of the following has layers of dense connective tissue that separate an individual skeletal muscle from adjacent muscles?

Fascia

Which of the following is the best explanation as to how muscles are attached bones?

fibers in a tendon intertwine with those in a bone's periosteum

Which of the following structures attaches muscles to bones?

tendon

Layers of dense connective tissue called ________ separate an individual skeletal muscle from adjacent muscles.

fascia

Muscles generate heat as they __________, which helps the body to _________.

contract, homeostasis

Muscular actions

provide muscle tone

The major function of the muscular system is;

movement

________ filaments are _________ toward the center of the sarcomere by ________ cross-bridges.

actin, pulled, myosin

When a muscle appears to be at rest, but its fibers are still undergoing some sustained contraction, this is called

muscle tone

The contractile response of a single muscle fiber to a muscle impulse is called a

twitch

As the intensity of stimulation increases, ________ of motor neurons continues until all motor units in that muscle are activated.

recruitment

When a muscle fiber is exposed to stimuli of increasing strength, it remains unresponsive until a certain level of stimulation is reached called the

threshold stimulus

During muscle contraction, the length of the thick and thin filaments

decreases

Correctly sequence the following steps of muscle contraction;

1. the sarcomeres shorten

2. an impulse is sent from the brain/spine

3. myosin and actin filaments overlap and slide past each other

4. the shortened muscle pulls on its attachment points resulting in movement

5. the whole muscle shortens (contracts)

2, 3, 1, 5, 4

After the use of ATP molecules, cells must regenerate ATP from ADP and phosphate. The molecule responsible for the regeneration of ATP is

creatine phosphate

Which of the following is true when skeletal muscles are used strenuously for even a minute or two?

muscle fibers must increasingly use anaerobic respiration to obtain energy

Which of the following is the neurotransmitter that stimulates a skeletal muscle fiber to contract?

acetylcholine

Which of the following types of molecules directly supply the energy for muscle fiber contraction?

ATP

Correctly sequence the steps of muscle contraction, at the level of a sarcomere, below:

1. New ATP binds to myosin, causing linkage to release

2. Muscle is in relaxed state

3. Cross-bridge binds actin to myosin

4. ATP splits, which provides power to "cock" the myosin cross-bridge

5. Exposed binding sites on actin allow the muscle contraction cycle to occur

6. Cross-bridge pulls actin filament (power stroke), ADP and phosphate are released from myosin

2, 5, 3, 6, 1, 4

Which of the following is considered the functional unit of skeletal muscles because it is the key part of the muscle that shortens?

sarcomere

The synapse between the motor neuron and the muscle fiber that it controls is called a

neuromuscular junction

Neurons that control muscles are called

motor neurons

Which of the following types of contractions is picking up a book bag an example of?

Isotonic

Which of the following types of contraction maintains posture?

tonic

When a muscle does not shorten but tension increases, the contraction is said to be

isometric

The muscle that can resist a prime mover and cause movement in the opposite direction is called the

antagonist

The movable end of a muscle is attached at its

insertion

Muscles that assist a prime mover are called

synergists

During anaerobic respiration, glucose molecules are broken down to release energy and in the process produce the byproduct called

actic acid

A motor neuron and the muscle fibers that it sends impulses to are known as a

motor unit

Which statement below describes the transverse system that functions in muscle contraction and relaxation?

The T system allows for communication with the sarcoplasmic membrane to allow for a depolarization

Which bands and/or zones in a sarcomere shorten when a skeletal muscle contracts?

H band and I band

After a strenuous workout, muscle cells contain increased quantities of all of the following EXCEPT

Glucose

Which statement below describes the transverse system that functions in muscle contraction and relaxation?

The T system allows for communication with the sarcoplasmic membrane to allow for a depolarization.

Which bands and/or zones in a sarcomere shorten when a skeletal muscle contracts?

H band and I band

In a sarcomere, cross bridges are found in

myosin

Which of the following sugars is produced under anaerobic conditions?

Lactose

After a strenuous workout, muscle cells contain increased quantities of all of the following EXCEPT

Glucose

Bones

form passageways for blood vessels and nerves

Treatment for a strained muscle is referred to as, "RICE" which stands for

rest, ice, compression, elevation

Which of the following includes neuromuscular disorders in which the primary symptom is muscle weakness due to dysfunction of muscle fibers?

myopathy

Which of the following is a rare, acquired muscle disease that is accompanied by a skin rash?

dermatomyositis

Which of the following is difficult to pinpoint and diagnose because it can mimic many other medical problems?

fibromyalgia

There are nine forms of ________ disease which together affect more than 50,000 Americans.

amyotrophic lateral sclerosis

Which of the following diseases affects 30,000 Americans at any one time and ultimately causes paralysis and death?

amyotrophic lateral sclerosis

Which of the above is a congenital disorder which impacts posture, balance, and motor functions?

cerebral palsy

Which of the following is a progressive neurodegenerative disease which leads to a loss of control over voluntary muscle movement?

amyotrophic lateral sclerosis

Which of the following is a chronic autoimmune disease which results in muscle weakness and fatigue due to a breakdown of the neuromuscular junction?

myasthenia gravis

Which of the following is a chronic disorder that is characterized by widespread muscle pain, stiffness, fatigue, and tenderness?

fibromyalgia

Which of the following is a genetic disease that damages muscle fibers?

muscular dystrophy

If muscles are completely immobilized due to enforced bed rest, muscles atrophy and strength can decrease at the rate of ________% per day.

5%

Complete immobilization of muscles due to enforced bed rest results in

atrophy

Which of the following is the cause of Hereditary Idiopathic Dilated Cardiomyopathy?

a genetic error in a form of actin found only in cardiac muscle

Which of the following is the cause of Charcot-Marie-Tooth Disease?

an extra gene that impairs the insulating sheath around affected nerve cells

Which of the following is the cause of Duchenne muscular dystrophy?

the absence of dystrophin

During rigor mortis, the actin and myosin filaments of the muscle fibers remain linked until

the muscles begin to decompose

Which of the following is true regarding rigor mortis?

it results from an increase in membrane permeability to calcium ions and decreases in ATP which prevents relaxation

Muscle fibers and their associated connective tissues are flexible but can tear if overstretched. This type of injury is called

muscle strain

In tendinitis

a tendon becomes painfully inflamed and swollen

A ________ is a painful condition in which a muscle undergoes a sustained involuntary contraction.

cramp

Which of the following best describes duchenne muscular dystrophy?

An inherited disorder which is x-linked and therefore more likely to affect males, it involves rapidly worsening muscle weakness.

Which of the following best describes amyotrophic lateral sclerosis?

Causes nerve cells to waste away or die rendering them incapable of sending messages to muscles, causing the muscles to atrophy.

Which of the following best describes fibrodysplasia ossificans progressiva?

A rare and progressive disease which causes muscles to gradually be converted into bony tissue.

Which of the following best describes Hereditary Idiopathic Dilated Cardiomyopathy?

A very rare inherited form of heart failure that is caused by a tiny genetic error in the form of actin found only in cardiac muscle.

Which of the following best describes Fibromyalgia?

A common syndrome which causes the sufferer to experience long-term, body-wide pain and tenderness in the joints, muscles, and other soft tissues.