Human Muscular System

• Muscle• specialized tissue that

has the ability to contract

• Functions– movement– protection– support– body heat

Muscle• 3 types• Smooth- (#1)• Diagram-

– a. nucleus– b. individual cell

• Characteristics-– involuntary muscle– each individual tapered cell

has a nucleus– not connected to bone– found in digestive organs,

blood vessels, birth canal

Muscle• Skeletal- (#2)• Diagram

– c. nucleus– d. striations– e. fiber (cell)

• Characteristics– voluntary muscle– striated cells that are

long fibers – fibers contain more than

one nucleus– connected to bones

Muscle• Cardiac (#3)• Diagram

– f. fiber– g. nucleus– h. netlike pattern– i. striations

• Characteristics – involuntary muscle– banded with striations– made of long fibers that

form a netlike pattern– cell nucleus present but

cells difficult to see– located only in the heart

Contraction of Skeletal Muscle

• Energy – ATP, Creatine

Phosphate

• Fatigue– Lack of ATP

• Soreness– lactic acid build up

from oxygen debt

Sliding Filament Hypothesis

• Explanation for muscle contraction

• fiber • fibril• filaments• filaments-

– actin- thin– myosin- thick

Points of Skeletal Muscle Attachment

• Origin– end of muscle attached

to a fixed bone– example- biceps at

shoulder

• Insertion– end of muscle attached

to a moving bone– example- biceps at

elbow

Opposable Skeletal Muscle

• Flexor– muscle that bends a

joint– example- biceps

• Extensor– muscle that

straightens a joint– example- triceps

• Muscle tone– slight contraction of

skeletal muscle

Muscle Groups

1 Deltoid

2 Biceps

3 Brachialis

4 Forearm/Wrist Flexors

5 Quadriceps

6 Sternomastoid

Muscle Groups

7 Pectoralis Major

8 Rectus Abdominus

9 External Oblique

10 Sartorius

11 Tibialis Anterior

12 Trapezius

Muscle Groups

13 Teres Major

14 Latissimus Dorsi

15 Gluteus Maximus

16 Hamstrings

17 Triceps

18 Forearm Extensors

19 Gastrocnemius

All Images- Clip Art