Skeletal Muscles - functions Flashcards
Occipitofrontalis
Raises eyebrows.
Orbicularis oculi:
Closes eyes.
Orbicularis oris:
Closes / pouts lips.
Masseter:
Mastication.
Temporalis:
Mastication.
Sternocleidomastoid:
Turns and tilts head.
Trapezius:
Pulls head backwards. Elevates (shrugs) and retracts shoulders. Pulls shoulders back.
Supraspinatus:
Initial abduction of shoulder.
Psoas:
Hip flexor (pulls thigh towards trunk).
Latissimus dorsi:
Extends, adducts and internally rotates arms.
Quadratus lumborum:
Bending backwards or sideways (vertebral extension or lateral flexion).
Erector spinae:
Extension of the vertebral column. Keeps spine upright
Pectoralis major:
Draws arms forward:
Shoulder flexion and medial rotation.
Rectus abdominis:
Vertebral flexion: Bending forward (crunches).
Internal and external obliques:
Rotation, bending sideways.
Respiratory Diaphragm
When contracts, it descends into the abdominal cavity, increasing the space for air to enter the lungs.
Deltoid:
Flexion, abduction and extension of shoulder joint.
Forward, side and back
Biceps brachii:
Stabilises shoulder joint; flexion and supination of forearm.
Triceps brachii:
Arm adduction; extends elbow (straightens arm)
Allows pushing movement by extending forearm.
Brachii = arm
Flexor carpi muscle:
Flexes the hand at the wrist joint.
Extensor carpi muscle:
Extends the hand at the wrist joint.
Gluteus maximus:
External rotation, abduction and extension of the hip joint.
Piriformis:
Externally rotates hips.
Deeper inside pelvis/buttocks
Sciatic nerve!
Hamstring:
Bends knee (flexes knee).
Rectus femoris:
Flexes hip and extends knee (e.g. kicking a football).
Thigh adductors:
Squeeze the thighs together.
Tibialis anterior:
Dorsiflexion and inversion of the foot (and supports medial arch of foot).
Soleus
Plantar flexion of the foot at the ankle.
Gastrocnemius
Flexes leg at the knee.
Plantar flexion of foot.
