Muscular System
Chapters 10 & 11
Did you know?
more than 50% of
body weight is
muscle
~ 650 muscles in
the human body
(we will memorize 53)
Some Muscle Terminology
Muscle fibers = muscle cells
Myo & sarco: word roots referring to muscle
(muscle)
(flesh)
Three types of muscle tissue:
Skeletal, cardiac, & smooth
Three Types of Muscle
Skeletal
Cardiac
Smooth
Functions of
Skeletal Muscles
•
•
•
•
•
Allow skeletal movement
Maintain posture
Support soft tissues
Guard entrances and exits
Maintain body temperature
Skeletal Muscle Anatomy
Skeletal muscle are:
• surrounded by connective tissue
• contain nerves
• contain own arteries and veins
• arranged in antagonistic pairs (e.g. triceps &
biceps)
• (antagonistic means opposing)
How Skeletal Muscles
Produce Movements
• Muscles exert a force
on tendons which pull
on bones
• Tendons connect
muscle to bone
brachialis
flexes forearm
•Origin: the
attachment of the
muscle to the bone
which remains
stationary
•Insertion: the
attachment of the
muscle to the bone
which moves
•Belly: between the
origin and insertion
Terminology
Insertion
Origin
Types of Movement
Flexion
p. 271-274
Extension
Hyperextension
Abduction, Adduction, & Circumduction
Rotation
Elevation & Depression
Protraction & Retraction