HSCI chapter 10

circular

convergent

fusiform

parallel

multipennate

bipennate

unipennate

agonist

• Prime mover

• Provides the most force

• Ex. Flexion

synergist

• Aid agonist

• Provide supplemental force

Antagonist

• Opposite action of agonist

• Usually located on opposite side of bone/ joint

• ex. extension

Occipitofrontalis

• Elevates eyebrows

• Wrinkles forehead

Orbicularis oculi

closes eye

orbicularis oris

closes and puckers lips

depressor anguli oris

Pulls corners of the mouth inferiorly to frown

zygomaticus major

elevates corners of mouth

Masseter

elevate mandible for actions like chewing

orbicularis oris

zygomaticus major

occipitofrontalis

depressor anguli oris

orbicularis oculi

Sternocleidomastoid

muscle that moves head and neck

External oblique

• Compresses abdominal cavity

• Flexes, laterally flexes (side bend), and rotates trunk

Internal oblique

• Compresses abdominal cavity

• Flexes, laterally flexes (side bend), and rotates trunk

• deep to external oblique

Rectus abdominis

• Compresses abdominal cavity

• Flexes trunk

Transversus abdominis

• Compresses abdominal cavity

• stabilize the core and spine, acting like a natural corset

Pectoralis minor

Depresses and protracts the scapula

Trapezius