Page 1
Muscular System
• Functions •Voluntary movement• Forms some sphincters• Protection of some organs• Stabilization of some joints• Posture• Heat production
Page 2
Muscular System
• Organs
– Muscles
Page 3
Muscular System
• Organs
– Muscles (includes tendons and aponeuroses)
Page 4
• Structure of Skeletal Muscles
– Muscle fibers
Page 5
• Structure of Skeletal Muscles
– Muscle fibers
Page 6
• Structure of Skeletal Muscles
– Muscle fibers
• Contractile units within:
Page 7
• Structure of Skeletal Muscles
– Muscle fibers
• Contractile units within:
– Sarcomeres
Page 9
• Structure of Skeletal Muscles
– Muscle fibers
• Contractile units within:
– Sarcomeres
Page 10
• Structure of Skeletal Muscles
– Muscle fibers
• Contractile units within:
– Sarcomeres
– Sarcomeres linked end-to end
Page 11
• Structure of Skeletal Muscles
– Muscle fibers
• Contractile units within:
– Sarcomeres
– Sarcomeres linked end-to end; form myofibrils
Page 13
• Muscle fibers bundled into fascicles
Page 14
• Muscle fibers bundled into fascicles
• Fascicles bundled to form the muscle
Page 15
• Connective Tissue in Muscle
Page 16
• Connective Tissue in Muscle
– Endomysium
Page 17
• Connective Tissue in Muscle
– Endomysium
– Perimysium
Page 18
• Connective Tissue in Muscle
– Endomysium
– Perimysium
– Epimysium
Page 20
• How Muscles Create Movement at Joints
– Muscles must cross joints
– Insertion pulled towards origin
Page 21
Fascicle Organization
• Parallel
– Greatest range of motion
Page 22
Fascicle Organization
• Parallel
• Pennate
Page 23
Fascicle Organization
• Parallel
• Pennate
– Strongest force of contraction
Page 24
Fascicle Organization
• Parallel
• Pennate
• Convergent
Page 25
• Fascicle Organization
• Parallel
• Pennate
• Convergent
– Greatest versatility
Page 26
• Fascicle Organization
• Parallel
• Pennate
• Convergent
• Circular
Page 27
Muscle-Bone Lever Systems
Page 28
F
Muscle-Bone Lever Systems
Page 29
F
Muscle-Bone Lever Systems
Page 30
R
F
Muscle-Bone Lever Systems
Page 31
R
F
E
Third-class lever
Muscle-Bone Lever Systems
Page 32
R
F
E
Third-class lever
Muscle-Bone Lever Systems
Page 33
F
E R
Third-class lever
Page 34
R
F
E
Third-class lever
Page 35
F
E R
Third-class lever
Page 36
F
E R
Third-class lever
Amplifies speed and
distance at the expense of
force
Page 38
R
F
E
Third-class lever
Muscle-Bone Lever Systems
Page 39
R
F
E
Third-class lever
Muscle-Bone Lever Systems
Page 40
R
F
E
Third-class lever
Muscle-Bone Lever Systems
Page 41
R
F
E
Second-class lever
Muscle-Bone Lever Systems
Page 42
R
F
E
First-class lever
Muscle-Bone Lever Systems
Page 43
Muscle Interaction
• Prime Mover
– Muscle most responsible for an action
• e.g.: abduction of arm: deltoid
Page 45
Muscle Interaction
• Synergistic muscles
– Assists prime mover
• e.g.: supraspinatus assists deltoid in abduction
Page 47
Muscle Interaction
• Fixator muscles
– Holds bone of origin steady
• e.g.: serratus anterior holds deltoid’s bone of origin steady during abduction
Page 49
Muscle Interaction
• Antagonistic muscles
– Action opposite that of the prime mover
• e.g.: lats and pects adduct
• must not contract during abduction
Page 50
• Muscle names may indicate the direction of the muscle fibers (e.g., transversus abdominis, external oblique).
Page 52
• Muscle names may indicate the direction of the muscle fibers (e.g., transversus abdominis, external oblique).
• A muscle may be named according to its location (e.g., temporalis, tibialis anterior).
Page 53
• The size of the muscle may be indicated in the name (e.g., gluteus maximus, adductor Iongus).
Page 54
• Some muscles are named on the basis of shape (e.g., deltoid, serratus anterior).
• Muscles may be named after their origin and insertion (e.g., sternocleidomastoid).
Page 55
• A muscle may be named according to its location (e.g., temporalis, tibialis anterior).
• Muscles may be named for their number of origins (e.g., triceps brachii, quadriceps femoris).