Muscular System

Question 1

Most muscles cross ______ ______, and are usually attached to articulating bones.

Answer 1

One joint

Question 2

The origin of the muscle is usually _______ and the insertion of the muscle is usually _______.

Answer 2

Proximal

Distal

Question 3

One bone remains ______ while the other bone is ______.

Answer 3

Stationary

Movable

Question 4

The muscle origin is located on the _______ bone while the insertion is usually on the _______ bone.

Answer 4

Stationary

Movable

Question 5

What is the fleshy portion of the muscle between tendons?

Answer 5

Belly or Body

Question 6

What is a lever?

Answer 6

A rigid structure that can move around a fixed point.

Question 7

What is a fixed point in the lever system called?

Answer 7

Fulcrum

Question 8

What is the effort arm?

Answer 8

Causes the movement (muscular contraction)

Question 9

What opposes the movement?

Answer 9

Load or resistance

Question 10

When does motion occur?

Answer 10

When the effort applied to the bone at the insertion exceeds the load.

Question 11

When the load is _______ to the fulcrum and the effort is ______ from the fulcrum. This is called mechanical advantage.

Answer 11

Closer
Further
Mechanical Advantage

Question 12

When the load is ________ from the fulcrum and the effort is applied _______ to the fulcrum, this is called mechanical disadvantage.

Answer 12

Further

Closer

Question 13

A first class lever is when the fulcrum is _______ the effort and the load.

Answer 13

Between

Question 14

A second class lever is when the fulcrum is between the fulcrum and the ______.

Answer 14

Effort.

Question 15

A third class lever is when the ______ is between the fulcrum and the load.

Answer 15

Effort

Question 16

What is the most common lever system in the musculoskeletal system?

Answer 16

Third-class lever

Question 17

________ _______ affects a muscle’s power and range of motion.

Answer 17

Fascicular arrangement

Question 18

The power of the muscle depends on what?

Answer 18

The total cross-sectional area

Question 19

What is it when the tension remains constant as muscle length decreases or increases?

Answer 19

Isotonic contraction

Question 20

What are isotonic contractions used for?

Answer 20

Body movements and for moving objects.

Question 21

What is a concentric contraction?

Answer 21

When the muscle shortens and produces movement to reduce the angle at a joint.

Question 22

What is an eccentric contraction?

Answer 22

When the muscle lengthens during a contraction.

Example; lower the book to the table.

Question 23

What is it called when a muscle does not change length?

Answer 23

Isometric contraction

Question 24

What is an isometric contraction?

Answer 24

When tension increases greatly without a change in muscle length because the tension generated is not enough to exceed the resistance of the object to be moved

Question 25

What is another name for the prime mover?

Answer 25

Agonist

Question 26

What is an antagonist?

Answer 26

The muscle that opposes the action of the prime mover, relaxes muscle.

Question 27

The biceps and triceps are _______ ______.

Answer 27

Antagonistic muscles

Question 28

What is a synergist?

Answer 28

The muscles that contract and stabilize the intermediate joints to prevent unwanted movements.

Question 29

What is a fixator?

Answer 29

The muscles that stabilize the origin of the prime mover so that the prime mover can act efficiently.

Question 30

How are skeletal muscles named?

Answer 30

``` Orientation of fascicles Size of muscle Shape of muscle Action of muscle Number of origins ```

Question 31

Orbicularis Oculi

Answer 31

``` Orbicularis Oculi Origin: Medial wall of orbit Insertion: Orbital Margin Action: Closes the eyes Innervation: Facial Nerve ```

Question 32

Occipitofrontalis | Frontal Belly

Answer 32

Occipitofrontalis Frontal Belly Origin: Epicranial aponeurosis Insertion: Skin superior to supraorbital margin. Action: Draws scalp anteriorly and raises eyebrows Innervation: Facial Nerve

Question 33

Occipitofrontalis | Occipital Belly

Answer 33

``` Occipitofrontalis Occipital Belly Origin: Occipital Bone Insertion: Epicranial aponeurosis Action: Draws scalp posteriorly ```

Question 34

Buccinator

Answer 34

Buccinator Origin: Alveolar process of maxilla and mandible. Insertion: Orbicularis Oris Action: Presses cheeks against teeth and lips, as in whistling.

Question 35

Orbicularis Oris

Answer 35

Orbicularis Oris Origin: Muscle Fibers surrounding opening of mouth Insertion: Skin at corner of mouth Action: Closes and protrudes lips.

Question 36

Masseter

Answer 36

Masseter Origin: Maxilla and zygomatic arch Insertion: Angle and ramus of mandible Action: Elevates mandible

Question 37

Temporalis

Answer 37

Temporalis Origin: Temporal fossa Insertion: Coronoid process and ramus of mandible Action: Elevates mandible

Question 38

What direction does the superior oblique move the eyeballs?

Answer 38

Inferiorly and laterally

Question 39

What direction does the inferior oblique move the eyeballs?

Answer 39

Superiorly and laterally

Question 40

What does the elevator pal-erase superioris do?

Answer 40

Raises the upper eyelids, opens eyes.

Question 41

Sternocleidomastoid

Answer 41

Sternocleidomastoid Origin: Manubrium and medial third of clavicle Insertion: Mastoid process and lateral half of superior nuchal line. Action: Bilaterally causes flexion, unilaterally causes head to rotate to opposite side of muscle belly.

Question 42

Sternohyoid

Answer 42

Sternohyoid Origin: Manubrium and medial end of clavicle Insertion: Body of hyoid bone Action: lowers hyoid bone.