PSIO 201 5th Edition Lecture 24 Outline of Last Lecture Cardiac and Smooth Muscle Outline of Current Lecture I Muscle Gross Anatomy I II Head Muscles III Respiratory Muscles IV Arm Muscles Current Lecture Characteristic Description Direction of muscle fibers Rectus Fibers run parallel to the midline Transverse Fibers run perpendicular midline Oblique Fibers run diagonal to the midline Size Maximus Largest Minimus Smallest Longus Longest Location Named for the bone s to which the muscle attaches or region within which th found Shape Deltoid Triangular shape Rhomboid Diamond shape Trapezius Trapezoid sh Number of origins Biceps Two origins Triceps Three origins Quadriceps Four origins Action Named for the action that the muscle performs These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute TABLE 2 Muscles of the face head and neck Muscle Location Occipitofrontalis Frontalis and Occipitalis Composite muscle that overlies the cranium the two muscles are connected by an aponeurosis Orbicularis oris Circular muscle that encircles the mouth Orbicularis oculi Circular muscle that encircles each eye Zygomaticus major Originates on the zygomatic bone and inserts on the skin at the corners of the mouth Action Frontalis Rai posteriorly Puckers the m Closes each e Pulls the corn Platysma Originates on the fascia of the chest and deltoid and inserts on the Depresses the mandible and skin below the mouth Temporalis Originates on the temporal bone and inserts on the mandible Masseter Originates on the maxillae and zygomatic bones and inserts on the Elevates and p mandible Sternocleidomastoid Originates on the sternum and clavicle and inserts on the mastoid process of the temporal bone Muscle Location Rectus abdominis Originates on the pubis and inserts superiorly on the lower ribs and xiphoid process External oblique Action Flexes the vertebral column and compresses the abdomen Originates laterally on the lower Rotation of the trunk results if ribs and inserts medially on the one side contracts If both sides iliac crest and linea alba contract together flexion of the vertebral column and compression of the abdomen is Elevates and r If one side co contract flexi the result Internal oblique Located deep to the external oblique the internal oblique originates laterally at the iliac crests and inserts medially at the linea alba and lower ribs Transverse abdominis Located deep to the internal oblique the transverse abdominis originates laterally Contraction of the transverse on the iliac crest and the abdominis compresses the cartilages of the lower ribs It abdomen inserts medially at the xiphoid process and linea alba Composite group of muscles Erector spinae Iliocostalis group that individually originate on Longissimus group Spinalis vertebral processes or ribs and group insert on superior processes of the vertebral column The internal oblique has the same action as the external oblique When one side contracts the muscles laterally flex and rotate the vertebral column When both contract the muscles extend the vertebral column and maintain erect posture Biceps brachii Muscle of the anterior arm with two points of origin on the Flexes and supinates the scapula It inserts on the radial forearm flexes arm tuberosity Brachialis Deep to the biceps brachii the brachialis originates on the Flexes the forearm anterior distal humerus and inserts on the proximal ulna Brachioradialis Originates on the distal humerus and inserts on the styloid process of the radius Triceps brachii Muscle of the posterior arm with three points of origin on the scapula and posterior humerus It inserts on the Flexes the forearm Extends the forearm and extends the arm olecranon process of the ulna
View Full Document
Unlocking...