Chapter 6 the Muscular System

The muscle that causes flexion of the forearm is the

biceps brachii.

The primary function of all muscle tissue is

contraction or shortening.

What does the term deltoid mean

Triangle shaped

In a skeletal muscle fiber, the sarcomere is a repetitive unit that consists of the entire region between the

Z-lines.

Myofibrils are primarily composed of

actin and myosin.

The bending or movement of a limb towards the midline of the body is known as

adduction.

The endomysium is a connective tissue that surrounds a

skeletal muscle fiber.

A tissue with striations and many flattened nuclei under the plasma membrane in each cell would be called

skeletal muscle.

sternocleidomastoid

sternum and clavicle, temporal bone, flexes neck and rotates head

pectoralis major

sternum clavicle and first to sixth ribs, proximal humerus, adducts and flexes humerus

Which of the following is a shared characteristic of cardiac and skeletal muscle

striations.

masseter

temporal bone, mandible, closes jaw

temporalis

temporal bone, mandible, closes jaw

What is the BEST definition of the origin of a muscle

the attachment of the muscle to a bone that is relatively fixed.

What type of muscle tissue contains intercalated discs

Cardiac

Which of the following is NOT a function of muscle tissue

Creation of action potentials

What does biceps mean

Divided into two

Which of the following is one of the muscles of the abdominal girdle

External oblique

Which of these muscles is located in the abdominal region

External oblique

Which of the following is a function of muscle

Generates heat; Produces movement; Maintains posture; Stabilizes joints

Which of the following are characteristic of cardiac muscle

Intercalated disks

Which of the following is true of an action potential

It is initiated by a temporary permeability to sodium ions which rush into the cell.; An action potential is a wave of electrical current.; An action potential is an all or nothing phenomenon - once started it goes to completion.; The result of the action potential is the contraction of the muscle cell.

Which of the following refers to one neuron and all the skeletal muscle cells it stimulates

Motor unit

Which of the following statements is true regarding energy generation for muscle contraction

One of the pathways for ATP regeneration is direct phosphorylation of ADP by creatine phosphate.; At rest and during light exercise, ATP is regenerated almost entirely by metabolic pathways that use oxygen.; Aerobic respiration refers to metabolic pathways that use oxygen.; The initial steps of glucose breakdown occur via a pathway called glycolysis, which does not use oxygen and is an anaerobic part of the metabolic pathway.

Which of the following statements is FALSE concerning the neuromuscular junction

One sensory neuron may innervate many muscle fibers

What is the muscle that encircles the eye

Orbicularis oculi

Which of the following correctly describes pronation

Putting your hands flat on a table

What is the name of the functional unit of a muscle cell

Sacromere

Which of the following is a hamstring muscle

Semimembranosus; semitendinosus; biceps femoris

Which of the following is the only muscle type that is nonstriated and involuntary

Smooth

Which of the following is a muscle of the head and neck

Temporalis; Zygomaticus; Buccinator Masseter

The thin filament is formed of what three molecules

Troponin, tropomyosin, actin

What specifically causes a muscle to contract

When the cocked heads of the myosin attach to the binding site the myosin heads pivot toward the center of the sarcomere.

The intercostals are found

between the ribs

Which muscle tissue is branched, striated, and uninucleate

cardiac

The "all-or-none" property of muscles is a phenomenon that occurs on the _____ level

cellular

platysma

connective tissue covering of superior chest muscles, tissue around mouth, pulls corner of mouth inferiorly

frontalis

cranial aponeurosis, skin of eybrows, raises eybrows

An aponeurosis

is a flat, sheet-like connective tissue attachment of one muscle to another muscle.

hamstring muscles

ischial tuberosity, proximal tibia, flex knee and extend hip

What are contractions that maintain the same tension; contractions that shorten the length of the muscle; are the type most often used in a workout in the gym

isotonic contractions

Which of the following can best be used to distinguish cardiac from smooth muscle

it is striated

The muscle that extends and adducts the humerus is the

latissimus dorsi.

latissimus dorsi

lower spine and iliac crest, proximal humerus, extends and adducts humerus

orbicularis oris

mandible and maxilla, skin and muscle around the mouth, closes and protrudes lips

buccinator

maxilla and mandible near molars, orbicularis oris, compresses cheeck as in whistling and holds food between teeth during chewing

When several muscles are contracting at the same time, the muscle that has the major responsibility for causing a particular movement is called the

prime mover.

soleus

proximal tibia and fibula, calcaneus, plantar flexes foot

rectus abdominus

pubis, sternum and fifth to seventh ribs, flexes verteberal column

Sacroplasmic reticulum

releases calcium into the sacroplasm during contraction

gluteus maximus

sacrum and ilium, proximal femur, extends hip

The plasma membrane of a muscle cell is most usually termed a

sarcolemma.

biceps brachii

scapula of shoulder girdle, proximal radius, flexes elbow and supinates forearm

deltoid

scapular spine and clavicle, humerus, abducts humerus

triceps brachii

shoulder girdle and proximal humerus, olecranon process of ulna, extends elbow

Leg adductors would

move legs medially

The alternating dark _______ and light________ give the muscle fiber its striated appearance

A band; I band

What is the term for a muscle that helps a prime mover

A synergist

The energy source that is directly responsible for muscle fiber contraction is

ATP.

What is the specific neurotransmitter that is released by motor neurons and stimulates skeletal muscle

Acetylcholine (Ach)

Name the two myofilaments that slide past one another to allow muscle cells to contract

Actin and myosin

Which of the following is a characteristic of skeletal muscle

Another name for skeletal muscle is voluntary muscle. Skeletal muscle cells are striated. Skeletal muscle tissue can contract rapidly and with great force, but tires easily and must rest after short periods of relativity.

What is the anatomical term for wide, sheetlike tendons

Aponeuroses

Which of the following statements is true

Tetanic contraction is normal and desirable and is quite different from the pathologic condition of tetanus.; When a muscle is stimulated so rapidly that no evidence of relaxation is seen and the contractions are completely smooth and sustained the muscle is said to be in tetanus or in tetanic contraction.; Tetanic contractions of muscles are smooth and prolonged muscle contractions which can be slight or vigorous depending on what work has to be done.; Complete tetanus is a smooth continuous contraction without any evidence of relaxation and results from a very rapid rate of stimulation.

In general, skeletal muscles insertions are found

The part of a muscle attached to the

Which of the following statements is true regarding muscle attachments and body movements

The point of attachment of a muscle to the immovable or less movable bone is called the origin.; Flexion is a movement, generally in the sagittal plane, that decreases the angle of the joint and brings the two bones closer together.; Abduction is movement away from the body and occurs in the coronal plane.; In circumduction of the arm the distal end of the limb describes a cone.

gastrocnemius

distal femur, calcaneus, plantar flexes foot and flexes knee

Movement of the jaw superiorly would be

elevation

Which of the following is a stomach muscle

external oblique; rectus abdominus; internal oblique

quadriceps group vasti

femur, tibial tuberosity via patellar ligament, all extends knee; rectus femoris also flexes hip on thigh

Muscles that are concerned with bracing actions are called

fixators.

If you work out in the gym and do some bicep curls, the contraction of the biceps would be considered

flexion

Smooth muscle fibers are characterized by

form the contractile tissue of the walls of many hollow organs.

orbicularis oculi

frontal bone and maxilla, tissue around eyes, blinks and closes eyes

During exercise, if there are sufficient oxygen molecules available in the muscle tissue

glucose is converted to pyruvic acid and then to water, carbon dioxide, heat, and ATP

The _______ does NOT cause movement at the knee joint

gluteus maximus

gluteus medius

ilium, proximal femur, abducts thigh steadies pelvis during walking

Muscle tissue is responsible for

movement.

The anatomical name for a muscle cell is a

muscle fiber.

The state of continuous partial contractions is called

muscle tone

The nuclei of skeletal muscle cells are pushed aside by long ribbonlike organelles called _______, which nearly fill the cytoplasm

myofibrils

trapezius

occipital bone and all cervical and thoracic vertebrae, scapular spine and clavicle, extends neck and adducts scapula

adductor muscles

pelvis, proximal femur, adduct thigh

The muscle that is mainly responsible for a particular movement is known as the

prime mover.

movable bone of the skeleton is termed

the insertion

The muscle whose action is dorsiflexion and inversion of the foot is the

tibialis anterior.

zygomaticus

zygomatic bone, skin and muscle at corner of lips, raises corner of mouth