1. The Muscular System: Function & Muscle Types

2. The Muscular System Functions: Produce movement Maintain posture
Stabilize joints
Generate heat

3. Muscle Types Three basic muscle types are found in the body
Skeletal muscle
Smooth muscle
Cardiac muscle

4. Skeletal Muscle Characteristics
Body Location: Most are attached by tendons to bones or, for facial muscles, to skin
Cell Shape and Appearance:
Single, very long cylindrical, multinucleate cells
Striated – have visible banding

5. Skeletal Muscle Characteristics
Regulation of Contraction: Voluntary – subject to conscious control
Speed of Contraction: slow to fast
Rhythmic contraction: no

6. Anatomy of a Skeletal Muscle
Each muscle fiber is enclosed in a delicate connective tissue sheath called an endomysium.
A bundle of muscle fibers are then wrapped in a coarser fibrous membrane called a perimysium.
Figure 6.1

7. Anatomy of a Skeletal Muscle
The bundle of fibers enclosed in the perimysium then forms a fascicle.
Many fascicles are then bound together by a even tougher connective tissue called an epimysium.
Figure 6.1

8. Anatomy of a Skeletal Muscle
The epimysia blend together to form strong, cordlike tendons which attach muscles to bone, cartilages, or connective tissue coverings.
Figure 6.1

9. Anatomy of a Skeletal Muscle
Tendon Functions:
Provide durability
Conserve space
Cross rough bony projections due to their tough collagen fibers

10. Smooth Muscle Characteristics
Body Location: Mostly in walls of hollow visceral organs (other then the heart)
Cell Shape and appearance:
Has no striations
Figure 6.2a

11. Smooth Muscle Characteristics
Regulation of Contraction: Involuntary – no conscious control
Speed of Contraction: Very slow
Rhythmic Contraction: Yes, in some
Figure 6.2a

12. Cardiac Muscle Characteristics
Body Location: found only in the heart
Cell Shape and Appearance:
Has striations
Joined to another muscle cell at an intercalated disc
Figure 6.2b

13. Cardiac Muscle Characteristics
Regulation of contraction: Involuntary
Speed of contraction: slow
Rhythmic contraction: yes
Figure 6.2b