The Muscular System Muscles are responsible for all types of body movement Three basic muscle types are found in the body Skeletal muscle Cardiac muscle Smooth muscle
Moving the human body Muscles of the body Muscle-an organ that contracts and gets shorter- this provides the force to move your body parts. Muscles of the body
Muscle Control Voluntary muscles- muscles that you are able to control Examples are leg and arm muscles Involuntary Muscles- you can not move them consciously. They just keep working Examples- heart
Muscular System Functions The muscular system moves the body. The body has over 600 muscles. Some muscles are called voluntary, that means that you choose to use them. How active you are depends on how much use they get! Some muscles are called involuntary because they work without you thinking about them. These are muscles like the heart and digestive system.
3 types of muscles Smooth Muscles- Which include the muscles of internal organs and blood vessels. These muscles move involuntary. Cardiac Muscle- Found only in the heart and also involuntary. Skeletal Muscles- Are voluntary and help you move.
Types Of Muscles Smooth Muscle- Digestive organs, Makes up 7-8% of your muscles. Involuntary
Types of Muscles cont. Cardiac Muscles- Only found in the heart. Involuntary. Makes up 3% of your muscles. By age 70 heart contracts 2.5 billion times (assume resting heart beat).
Types of Muscles cont. Skeletal Muscles- Makes up 90% of your muscles. Voluntary- These are the muscles that you can move.
Skeletal Muscle Characteristics Most are attached by tendons to bones
Skeletal Muscle Attachments Epimysium blends into a connective tissue attachment Tendon – cord-like structure Aponeuroses – sheet-like structure Sites of muscle attachment Bones Cartilages Connective tissue coverings
Smooth Muscle Characteristics Has no striations Spindle-shaped cells Single nucleus Involuntary – no conscious control Found mainly in the walls of hollow organs
Cardiac Muscle Characteristics Has striations Usually has a single nucleus Joined to another muscle cell at an intercalated disc Involuntary Found only in the heart
Function of Muscles Produce movement Maintain posture Stabilize joints Generate heat
Muscles and bones work together Working together A review
Why do I need tendons? Try This... Tendons attach my muscles to my bone helping my body move. Feel your tendon right above your heel in the back of your leg. This is the thickest tendon in your body. Try This...