Bio 141 Lab #8

Pectoralis Major

What is this muscle?

Pectoralis Minor

What is this muscle?

serratus anterior

What is this muscle?

intercostals (external)

What is this muscle?

intercostals (internal)

What is this muscle? #2

Diaphragm

What is this muscle?

External oblique

What is this muscle?

Internal Oblique

What is this muscle?

Transverse Abdominis

What is this muscle?

Rectus Abdominis

What is this muscle?

linea alba

What is this muscle?

tendinous inscriptus

What is this muscle?

What is the origin of the pectoralis major?

Clavicular head-medial half clavicle. Sternocostal head-lateral manubrium and sternum, six upper costal cartilages and external oblique aponeurosis

What is the insertion of the pectoralis major?

Lateral lip of bicipital groove of humerus and anterior lip of deltoid tuberosity

What is the action of the pectoralis major?

Clavicular head:flexes and adducts arm. Sternal head: adducts and medially rotates arm . Accessory for inspiration

What is the origin of the external oblique?

Anterior angles of lower eight ribs

What is the insertion of the external oblique?

Outer anterior half of iliac crest, inguinal lig, public tubercle and crest, and aponeurosis of anterior rectus sheath

What is the action of the external oblique?

Supports abdominal wall, assists forced expiration, aids raising intraabdominal pressure and, with muscles of opposite side, abducts and rotates trunk

What is the origin of the internal oblique?

Lumbar fascia, anterior two thirds of iliac crest and lateral two thirds of inguinal ligament

What is the insertion of the internal oblique?

Costal margin, aponeurosis of rectus sheath (anterior and posterior ), conjoint tendon to pubic crest and pectineal line

What is the action of the internal oblique?

Supports abdominal wall, assists forced respiration, aids raising intra-abdominal pressure and, with muscles of other side , abducts and rotates trunk. Conjoint tendon supports posterior wall of inguinal canal

What is the origin of the rectus abdominis

Pubic crest and pubic symphysis

What is the insertion of the rectus adominis?

5, 6, 7 costal cartilages, medial inferiorcostal margin and posterior aspect of xiphoid

What is the action of the rectus adominis?

Flexes trunk, aids forced expiration and raise intra-abdominal pressure