Bio 221 Lab 7

origin, insertion & action

all 600 muscles have this

Origin & insertion

points of attachment

origin, insertion & action

all 600 muscles have this

Origin & insertion

points of attachment

origin

where muscle attaches for leverage or anchor - usually larger and more stable

insertion

where muscle attaches for movement - usually smaller & less stable

action

the movement that occurs when a muscle contracts, moving the insertion towards the origin - what actually happens depends on origin and insertion

sternocleiodomastoid

origin - manubrium of sternum, sternal end of clavicle. Insertion - mastoid process of temporal bone. Action - lateral flexion

kicking knee - extension

bending knee backwards - flexion

flexion & extension

rotating hand

pronation & supination

eye muscles

superior oblique, superior rectus, lateral rectus, inferior oblique, inferior rectus, medial rectus (OBLIQUES POINT OUT MEDIAL)

Intercostal muscles

muscle between the ribs

Internal costal muscles

goes into mid line - towards the chin - looks like of like an A line

External costal muscles

Start externally, looks like V line

Rectus abdominis

6 pack muscles - on top!

External obliques

a pair of large, flat muscles on the sides of your abdomen that help with trunk flexion, lateral flexion, and rotation

Internal obliques

located on the lateral sides of the abdomen, deep to the external oblique muscles

transverse abdominis

transverse abs

Rotator cuff

group of 4 muscles attached to the scapula

SITS: supraspinatus, infraspinatus, teres minor, subscapularis