Chapter 10

True or False: Muscles can only push; never pull

• True

• False

Which one does NOT correctly match up regarding functional groups

• Prime mover (agonist): produces specific movement

• Antagonist: reduces undesirable force

• Synergist: helps prime mover

• Fixator: immobilizes bone or muscle origin

Answer explanation

Antagonist: opposes or reverses particular movement

Which is NOT used when naming skeletal muscles

• direction of muscle fibers

• muscle functional group

• muscle action

• number of origins

Answer explanation

All things that influence naming of muscles

- location

- shape

- size

- direction of fibers

- number of origins

- location of attachments

- action

Which of the following does not match correctly regarding fascicle arrangements

• circular: fascicles arranged in concentric rings

• convergent: converge towards single tendon

• parallel: fascicles parallel bone

• fusiform: spindle shaped muscles with parallel fibers

Answer explanation

parallel: fascicles parallel to long axis of straplike muscle

Fascicles determine

• range of movement

• type of movement

• mechanical advantage

• mechanical disadvantage

Answer explanation

amount of movement when muscles shortens

Which of the follow does not match correctly regarding lever systems

• lever: rigid bar (bone) that moves on a fixed point called pennate

• lever: rigid bar (bone) that moves on a fixed point called fulcrum

• effort: force applied to lever to move resistance (load)

• load: resistance moved by the effort

Answer explanation

pennate is a fascicle arrangement

Which is correct regarding classes of lever system and what is in the middle

(ex. fulcrum -> load <- effort)

• first class: load

• second class: fulcrum

• third class: effort

• third class: load

Answer explanation

In the middle is (FLEe)

First class- fulcrum

Second class: load

Third class: effort

What is NOT true of facial muscles

• They are inserted into skin not bone

• Innervated by cranial nerve VII

• Important for nonverbal communication

• Facial expression muscles are separated into three groups

Answer explanation

Facial expression muscles consist of two groups:

–Muscles of the scalp

–Muscles of the face

Which is not true about muscles of mastication

• Prime movers of jaw closure: temporalis and masseter

• Grinding movement: petrygoids

• Chewing role: buccinator

• Hypoglossus: protracts tongue

Answer explanation

Hypoglossus moves tongue not part of mastication

What muscle does not move the tongue

• Geinoglossus

• Hyoglossus

• Geniohyoid

• Styloglossus

Answer explanation

Glossus= tongue