Types of muscle bioengeenring.pptx

Muscle biophysics

1. Types of Muscle

2. What are muscles? Muscle , are excitable tissue like the nervous tissue There are about 700 muscles that are connected to the bones of the body. About 40-50 per cent of the body weight of a human adult is contributed by muscles The Muscles are involved movement of the body.

3. Types of muscle Based on their location, three types of muscles are identified : ( i ) Skeletal muscle (ii) Visceral also called smooth muscle and (iii) Cardiac muscle

4. Skeletal muscle When you think about your muscles, you are probably thinking about  skeletal muscle . Skeletal muscles is voluntary muscles. When you volunteer, you choose to do something. It's the same for your skeletal muscles. Your leg won't kick a soccer ball until you choose to move it.

5. Skeletal muscles are  striated muscles , which is a fancy way of saying they look striped when you view them under a microscope. They're the only type of muscle that is voluntary, so any muscle that you can move by thinking about it is a skeletal muscle.

6. Structure of a skeletal muscle Attached to bones at both ends by tendons When you contract a skeletal muscle it shortens, pulling the bone along with it and thus causing movement. Fusiform in shape with tapering ends Has a belly & tendons on either side

7. Structure of a skeletal muscle Myofibrils Muscle Fascicles Muscle fibres Muscle fibres Myofibril

8. The arrangement of thick and thin filaments in the myofibrils results in the striated appearance of muscle fibers

9. Properties of Skeletal Muscle The skeletal muscles have the following properties: Extensibility: It is the ability of the muscles to extend when it is stretched. Elasticity: It is the ability of the muscles to return to its original structure when released. Excitability: It is the ability of the muscle to respond to a stimulus. Contractility: It is the ability of a muscle to contract when in contact with a stimulus.

10. Mechanism of muscle contraction Mechanism of muscle contraction is best explained by the sliding filament theory which states that contraction of a muscle fibre takes place by the sliding of the thin filaments over the thick filaments.

11. Skeletal Muscle Function The important skeletal muscle function: The skeletal muscles are responsible for body movements such as typing, breathing, extending the arm, writing, etc. The muscles contract which pulls the tendons on the bones and causes movement. The body posture is maintained by the skeletal muscles. The gluteal muscle is responsible for the erect posture of the body. The sartorius muscles in thighs are responsible for body movement. The skeletal muscles also regulate body temperature. After a strenuous exercise, the body feels hot. This is due to the contraction of skeletal muscles which converts energy into heat.

12. Smooth Muscle Smooth muscle  is the type of muscle that makes up the walls of many internal organs and structures, like your digestive tract, blood vessels, and bladder. Also called visceral muscle. The most striking feature is the lack of striations and stripes. Compared to the other types, smooth muscle looks like smooth sheets, hence the name.

13. You don't have any control over these muscles, so they are involuntary muscles. smooth muscles are always at work behind the scenes, helping you do all kinds of things necessary for survival. The smooth muscles found in your esophagus , stomach, and intestines contract and relax to push food through your digestive tract. Smooth muscles in the walls of your blood vessels contract and relax to adjust how much blood flows through them.

14. Structure of smooth muscle

15. Types of smooth muscle S i ngl e u n i t s m oo th m u s c le M u li t i u n i t sm o o th m u s c l e.

16. Single unit smooth muscle Single-unit muscle has its muscle fibers joined by gap junctions so that the muscle contracts as a single unit. P r e s e n t i n ho l l o w v i s ce r a (organs) l i k e G I T , U t e r u s , U r e te r, U r i n a r y B lad der & R e sp i r at o r y t r a c t .

17. Multiunit smooth muscle Multiunit smooth muscle cells rarely possess gap junctions, and thus are not electrically coupled. As a result, contraction does not spread from one cell to the next, but is instead confined to the cell that was originally stimulated. This type of tissue is found around large blood vessels, in the respiratory airways, and in the eyes.

18. Cardiac Muscles The cardiac muscles is a muscles tissue found in the heart wherein it is performing and bringing about coordinated contractions which enable the heart to pump blood. Cardiac muscles are striated and involuntary muscles.