Anatomy Exam One- I5 Muscular System

Muscular system

composed of all of the muscles of the body and is concerned with movements of the total body as well as movements within the body

Properties of muscle tissue

1. Contractility

2. Extensibility

3. Elasticity

4. Irritability

5. Tonus

Contractility

muscle tissue to shorten or contract

Extensibility

muscle tissue to be extended or stretched within limits

Elasticity

muscle tissue to return to its original state after being stretched

Irritability

muscle tissue to react to external stimuli

Tonus

the state in which a muscle is partially contracted allowing it to react instantly when stimulated

Smooth muscle

long spindles thick in the center and pointed at the ends (football)

• one nucleus per cell

• no striations

• comprises viscera and vessels

Cardiac muscle

• striated

• one nucleus per cell

• located only in the heart

Skeletal muscle

• composed of long cells (up to 4 cm in length)

• multinucleated

• striated

• attach to bones and cause movement

Fascia

connective tissue layer that surrounds muscles

1. permits gliding

2. passage for nerves and vessels

3. rich blood and nerve supply

7 types of muscle attachments

1. Bone

2. Cartilage

3. Skin

4. Fascia

5. Ligaments (attach bone to bone)

6. Tendons (attach muscle to bone)

7. Aponeurosis (flattened tendon)

Muscle attachment

origin and insertion