Presentation on theme: "“the power system”. Nearly half our weight comes from muscle tissue. There are 650 different muscles in the human body. Muscles give us form and shape."— Presentation transcript:
“the power system”
Nearly half our weight comes from muscle tissue. There are 650 different muscles in the human body. Muscles give us form and shape. Muscles produce most of our body heat.
Responsible for all body movement. Responsible for body form and shape (posture) Responsible for body heat and maintaining body temperature.
Skeletal Smooth Cardiac Sphincter
Attached to bone Striated (striped) appearance VOLUNTARY Contract quickly, fatigue easily, can’t maintain contraction for long period of time
Each skeletal muscle cell contains many nuclei Muscle cells are known as muscle fibers Cell membrane is call sarcolemma Cytoplasm is called sarcoplasm
Visceral (organ) muscle Found in walls of digestive system, uterus and blood vessels Cells small and spindle- shaped INVOLUNTARY Controlled by autonomic nervous system Act slowly, do not tire easily, can remain contracted for long time
Found only in the heart Striated and branched Involuntary Cells are fused – when one contracts, they all contract
special circular muscles in openings of esophagus and stomach, stomach and small intestine, anus, urethra and mouth.
CONTRACTIBILITY – the ability of a muscle to reduce the distance between the parts of its contents or the space it surrounds. EXCITEABILITY (IRRITABILITY) – the ability to respond to certain stimuli by producing impulses.
EXTENSIBILITY – the ability to be stretched. ELASTICITY – ability of muscle to return to its original length when relaxing.
Location: – frontalis-forehead Size: – gluteus maximus Direction of fibers: external abdominal oblique Number of origins: – Biceps-two headed muscle in humerus Location of origin and Insertion: sternocleidomastoid- origin in sternum
Action flexor: – flexor carpi ulnaris- flexes the wrist Extensor: – extensor carpi ulnaris- extends the wrist Levator and Depressor: – depressor anguli oris-depresses the corner of the mouth, raises or lowers body parts
Muscles move bones by pulling on them. As a muscle contracts, it pulls the insertion bone closer to the origin bone. Movement occurs at the joint between the origin and the insertion. Rule: A muscle’s insertion bone moves toward its origin bone. Groups of muscles usually contract to produce a single movement.
Sarcolemma: muscle cell membrane Synaptic Cleft: gap between the axon and the muscle cell.
MOTOR UNIT – a motor neuron plus all the muscle fibers it stimulates. NEUROMUSCULAR JUNCTION – the junction between the motor neuron’s fiber which transmits the impulse – and the muscle cell membrane. ACETYLCHOLINE – chemical neurotransmitter, diffuses across the synaptic cleft (carries impulse across synaptic cleft)
MUSCLE FATIGUE – caused by the accumulation of lactic acid in the muscles. OXYGEN DEBT – after exercise, the amount of oxygen needed by the muscle to change lactic acid back to glucose. MUSCLE TONE - When muscles are slightly contracted and ready to pull.
Improves: -Coordination of all muscles involved -Respiratory and circulatory system to supply needs of active muscular system -Elimination of excess fat -Joint movement involved with that muscle activity
Strength (capacity to do work) is increased with training Muscle size increase due to change in the sarcoplasm (cytoplasm found in the individual skeletal muscle fibers) Not the increase in the number of muscle fiber cells
Tendons: non-elastic cords that attach muscles to bones Bones are connected at joints
Dome-shaped muscle that separates the abdominal and thoracic cavities, aids in breathing
ATROPHY – wasting away of muscle due to lack of use. If we fail to exercise our muscles weaken and become flaccid ex. Quadriplegics, elderly on bedrest, extremity in a cast, etc.
Massage of these muscles is essential in providing the proper physiotherapy or a general sense of comfort and well-being to a patient, also prevents atrophy in debilitated patients
HYPERTROPHY – an increase in the size of the muscle cell. when over exercise the size of the muscle fibers increase due to a change in the sarcoplasm (not due to an increase in number of muscle fiber cells)
STRAIN – tear in the muscle resulting from excessive use. Bleeding inside the muscle can result in pain and swelling. Ice packs will help stop bleeding and reduce swelling. – RICE : rest, ice, compression, elevation
Rehabilitation: retaining of injured or unused muscles MYALGIA – muscle pain
TENDONITIS – inflammation of a tendon
MUSCLE SPASM (cramp) – sustained contraction of the muscle, usually because of overuse.
Or wry neck, may be due to an inflammation of the trapezius and/or Sternocleidomastoid muscle