Unit a- 1.04 remember the structures of the muscular system

1. Unit a- 1.04remember the structures of the muscular system ~What are the structures of the muscular system?

2. The muscular system… • Contraction of muscles gives the body the ability to move • Nearly ½ of the body’s weight comes from muscles • There are over 650 different muscles in the human body • Muscles are responsible for all body movement • Three main responsibilities: • Body Movement • Body form and shape, to maintain posture • Body heat, to maintain body temperature

3. Muscles • Skeletal: • Attached to the bones • Striped or striated • Voluntary muscles

4. muscles • Cardiac: • Found only in the heart • Involuntary • When one cell receives a signal to contract, all neighboring cells are stimulated and they contract together to produce the heart beat

5. Muscles • Smooth Muscles • Small and spindled shape • Called smooth muscles because they are • unmarked by striations • Unattached to the bones • Act slowly , do not tire easily, and can remain contacted for a long time

6. muscles • Sphincter- • Dilator muscles • Circular muscles in the openings between the esophagus and stomach and the stomach and small intestine • Found in the walls of the anus, urethra, and the mouth

7. Connective tissue

8. Connective Tissue • Tendons- white, glistening bands attaching skeletal muscles to the bones • Fascia- band or sheet of fibrous membranes covering or binding and supporting muscles

9. Skeletal Muscles • Skeletal (voluntary) muscles are attached to, and help to move, the skeleton • Lines the walls of the oral, abdominal, and pelvic cavities • Named by location, size, direction, number of origins, location or origin and insertion, and action

10. Skeletal muscles • Location- frontalis- forhead • Size- gluteus maximus- largest muscle in the buttock • Direction of fibers- external abdominal oblique- edge of the lower rib cage • Number of origins- biceps- two headed muscle in the humerus • Location of origin and insertion- sternocleidomastoid- origin in the sternum • Action flexor- flexor carpi ulnaris- extends the wrist • Extensor- extensor carpi ulnaris- extends the wrist

11. Skeletal musclehead and neck • Control human facial expressions such as anger, fear, grief, joy, pleasure, and pain • Head Muscles- expression, mastication (chewing), tongue, pharynx, soft palate • Neck Muscles- moving the hand, moving the hyoid bone and the larynx, moving the upper ribs

13. Torso and trunk • The trunk muscles control breathing and the movements of the abdomen and the pelvis

15. Upper extremities • Muscles of the upper extremity help to move the shoulder (scapula) and arm (humerus) and the forearm, wrist, hand, and fingers.

17. Lower extremities • Assist in movement of the thigh (femur), leg, ankle, foot and toes.

19. A. cartilage B. tendon C. skeletal D. joint E. ligament • Muscles, such as the bicep, that connect to bone and produce an action • 2. Connects muscle to bone • 3. Cushion between bones • 4. Where 2 bones meet • 5. Connects bone to bone • 6. A sprain is a tear in a ______________ • 7. A strain is a tear in a muscle or ____________. • 8. Always splint the ___ above and below a fracture