The Muscular System

1. The Muscular System By: Katelyn Kulik

2. Functions • The muscular system is responsible for both physical movement and movement of food through the body. • An example would be cardiac muscles helping the heart pump blood to the body.

3. Types of muscle tissue: • There are three main types of tissues in the muscular system. • There are skeletal muscles, cardiac muscles and smooth muscles. • Skeletal muscles make up most of the muscular system and control the movement of your bones. • Cardiac muscles or heart muscles are only located in the heart they contract to help the heart pump blood to the body. • Smooth muscles make up your cardiovascular system.

4. What is muscle fatigue? • Muscle fatigue is the outcome of working muscles to much which causes the muscles lose their ability to contract.

5. Exercise and skeletal muscle Skeletal muscles when worked begin to gradually grow in strength and begin to fatigue less quickly. Skeletal muscles can usually be consciously controlled.

6. Flexors and extensors • Flexor- A muscle that bends a joint • Extensor- A muscle that straightens a joint • (Ex.) Hands and Fingers, Flexors= Carpi Radialis, Carpi Ularis, Extensors= Carpi Radialis Long, Carpi RadialisBrevior, Carpi Ulnaris. • (Ex.) Hamstring= Flexor, Quadriceps= Extensor • (Ex.) Biceps= Flexors, Triceps= Extensors

7. Muscle disorders • Muscle Fatigue- The physiological inability of a muscle to contract. When ATP is absent, Continuous contractions occur causing muscle cramps. (Ex. When a runner does not stretch before a race or over exerts their muscles they may suffer from muscle cramps.)

8. Connective tissues:Loose connective tissue • The most widespread connective tissue of the body • It is used to attach the skin to the underlying tissue • It also surrounds and supports the blood vessels • Ex: supports and connects structures of the body

9. Types of loose connective tissue: • Collagen fibers  made of collagen and consist of bundles of fibrils that are coils of collagen molecules • Elastic fibers  made of elastin and are stretchable • Reticular fibers  join connective tissues to other tissues

10. Fibrous connective tissue: • Found in tendons and ligaments. • Ex: fiber in meats A thick layer of perimysium.

11. Specialized connective tissues: • Adipose  stores fat • Cartilage  composed of tightly packed collagenous fibers on a rubbery gelatinous substance called chondrin. (Ex: skeletons of human embryos) Fat cells Human embryo

12. Specialized connective tissue cont: • Bone: mineralized connective tissue that contains collagen and calcium phosphate • Blood: the matrix is the plasma and erythrocytes, leukocytes and platelets are suspended in the plasma. Bone connective tissue Blood connective tissue

13. Function of tendons Tendons- Cord or band of inelastic tissue connecting a muscle with its boney attachment.

14. Extra Vocab • Muscle Fibers- Skeletal Muscle tissue that is made up of elongated cells • Fascicles- Dense bundles of skeletal muscle fibers • Smooth muscles- Involuntary muscles because most movements cannot be consciously controlled • Myofibrils- Bundles of thread like structures in the skeletal muscle fibers. • Myosin- Thick filaments in Myofibrils • Actin- Thin filaments in Myofibrils

15. Extra Vocab • Z-line- The end points of the thin actin filaments connect to this structure. • Sarcomere- The region from one z-line to another • Origin- The point where a muscle attaches to a stationary bone. • Insertion- The point where a muscle attaches to a moving bone.

16. Bibliography • http://ect.downstate.edu/courseware/histomanual/connective.html • http://biology.about.com/od/anatomy/a/aa122807a.htm • http://hrsbstaff.ednet.ns.ca/clattem/Health/Cardio/Cardio%20Home%20Page.htm • http://chestofbooks.com/health/anatomy/Human-Body-Construction/2-The-Flexors-And-Extensors-Of-The-Wrist.html • http://www.siumed.edu/~dking2/intro/ct.htm • http://library.thinkquest.org/2935/Natures_Best/Nat_Best_Low_Level/Muscular_page.L.html