1. Muscular System

2. Muscular System Muscles are responsible for all types of body movement
3 basic muscle types are found in the body
Skeletal muscle
Cardiac muscle
Smooth muscle

3. Characteristics of Muscles
Muscle cells are elongated (muscle cell = muscle fiber)
Contraction of muscles is due to the movement of microfilaments
All muscles share some terminology
Prefix myo refers to muscle
Prefix mys refers to muscle
Prefix sarco refers to flesh

4. Comparison of Types of Muscle

5. Types of Muscle, cont.

6. Skeletal Muscle Characteristics
Most attach to bones by tendon
Cells are multinucleate
Striated—have visible binding
Voluntary
Cells surrounded & bundled by connective tissue

7. Smooth Muscle Characteristics
Has no striations
Spindle-shaped cells
Single Nucleus
Involuntary—no conscious control
Found mainly in the walls of hollow organs

8. Characteristics of Cardiac Muscle
Has striations
Usually has a single nucleus
Joined to another cardiac muscle cell
Involuntary
Found only in the heart

9. Skeletal Muscle Functions of Skeletal Muscle
Muscle Fibers blend into a connective tissue attachment
Tendon—cordlike structure
Aponeurosis—sheet-like structure
Properties of Muscle
Irritability – ability to receive and respond to a stimulus
Contractibility – ability to shorten when an adequate stimulus is received
Extensibility – ability to lengthen when an adequate stimulus is received
Elasticity – ability to return to normal shape
Functions of Skeletal Muscle
Produce Movement
Maintain posture
Stabilize joints
Generate Heat
Sites of Muscle Attachment
Bones
Cartilage
Connective tissue coverings

10. Anatomy of a Muscle Cell

11. Skeletal Muscle Strength
Two speeds at which muscles contract
Slow Twitch - Have more endurance, have many more mitochondria to give them lots of energy.
examples of when slow-twitch are needed:
Marathons and swimming

12. Fast Twitch Muscles
Fatigue Easier because of fewer mitochondria, but gives lots of strength. Rely more on anaerobic respiration.
Examples where fast-twitch would be used:
Sprinting, and weight lifting

13. Muscle Strength
Some people have a high ratio of slow-twitch to fast-twitch, and some have a high ration of fast-twitch to slow-twitch
Most people are in between

14. Cellular Respiration Where does it occur? = CO2 + H2O + ATP (energy)
Sugar (C6H12O6 + O2
= CO2 + H2O + ATP (energy)
How do the Respiratory, Circulatory, and Muscular System all tie together?
How does the nervous system work with all of these systems as well?