A&P 1 lab 6: muscles of chest and abdomen

pectoralis major origin

sternal end of clavicle
costal cartilages of ribs 1-6
sternum

pectoralis major insertion

intertubercular groove
greater tubercle of humerus

pectoralis major action

flexion
adduction
medial rotation of humerus

pectoralis minor origin

ribs 3-5

pectoralis minor insertion

coracoid process

pectoralis minor action

draw scapula forward and downward

serratus anterior origin

superficial/external surface of ribs 1-8

serratus anterior insertion

medial border of scapula

serratus anterior action

protracts scapula
pulls inferior angle of scapula lateral + upward

rectus abdominus origin

pubic symphysis and superior margin of pubis

rectus abdominis insertion

xyphoid process
costal cartilages of ribs 5-7

rectus abdominus action

flexes lumbar region of vertebral column

transverse abdominus origin

iliac crest
inguinal ligament

lumbar fascia

cartilages of ribs 6-12

transverse abdominus insertion

linea alba
pubic crest

transverse abdominus action

compress abdominal contents

external oblique abdominus origin

lower 8 ribs

external oblique abdominus insertion

linea alba
pubic crest

internal oblique abdominus origin

lumbar fascia
iliac crest
inguinal ligament

internal oblique abdominus insertion

linea alba
pubic crest
lowest 3 ribs

ext/int oblique abdominus action

flex vertebral column + compress abdominal wall