Kinesiology 2222A/B Lecture Notes - Lecture 6: Orbicularis Oculi Muscle, Quadriceps Femoris Muscle, Orbicularis Oris Muscle

• School: Western University
• Department: Kinesiology
• Course: Kinesiology 2222A/B
• Professor: gillian corbo

Document Summary

Muscles and nerves of the head, neck and trunk. How muscle produces movement: a muscle must span at least one joint to produce movement, muscle belly is contractile, attachment point on bones via tendons, also skin (mm. of facial expression) Origin vs. insertion: origin is usually proximal, usually remains fixed during contraction. Insertion is usually distal: usually moves towards origin. Types of muscle contraction: concentric muscle shortens. Prime mover/ agonist main muscles responsible for producing movement. Synergist assists agonist in producing movement: antagonist opposes the action of agonist i. e relaxation during contraction. Location: pectoralis, intercostal, brachialis: attachments: sternocleidomastoid, stylohyoid, number of heads: biceps brachii, quadriceps femoris. Function: extensor digitorum, erector spinae: direction of fibers: transverse abdominus, external oblique. What do these muscles do: muscles of facial expression move the face of the skin to producefacial expressions, muscles of mastication move the mandible to assist in chewing. Extraocular muscles move the eye in different directions.