Structure of Skeletal Muscle Composed of striated muscle cells (=muscle fibers) and connective tissue. Heat production – contraction of muscles produces most of the heat required to maintain body temperature. These contractions don’t produce movement yet hold our muscles in position. įunctions of Skeletal Muscle Maintenance of posture or muscle tone We are able to maintain our body position because of tonic contractions in our skeletal muscles. Levators – muscle that raise a body part. įunctions of Skeletal Muscle Movement Antagonists – muscles and muscle groups usually work in pairs – example the biceps flex your arm and its partner the triceps extend your arm. The one that is most responsible for the movement is the Prime Mover (agonist). All of the muscles responsible for the movement are synergists. Synergists – any movement is generally accomplished by more than one muscle. And yes… they do fatigue Muscle fatigue activity what substance forms causing muscle fatigue? įunctions of Skeletal Muscle Movement – muscle move bones by pulling not pushing. Skeletal Muscle Attached to skeleton by tendons Causes movement of bones at the joints. Skeletal Muscle Fibers are long and cylindrical Has many nuclei Has striations Have alternating dark and light bands Voluntary Healthy cardiac muscle NEVER fatigues or else… Smooth Muscle They fatigue… but very slowly Found in the circulatory system Lining of the blood vessels Helps in the circulation of the blood Found in the digestive system Esophagus, stomach, intestine Controls digestion Found in the respiratory system Controls breathing Found in the urinary system Urinary bladder Controls urination Ĭardiac Muscle Cells are branched and appear fused with one another Has striations Each cell has a central nuclei Involuntary Ĭardiac Muscle Found ONLY in the heart Contractions of the heart muscles pump blood throughout the body and account for the heartbeat. No striations Single nuclei Involuntary Contracts slowly Smooth Muscle Fibers are thin and spindle shaped. Muscle Classification Functionally Voluntarily – can be moved at will Involuntarily – can’t be moved intentionally Structurally Striated – have stripes across the fiber Smooth – no striations įunctions of the Muscles Movement Maintenance of posture and muscle tone Heat production Protects the bones and internal organs.
It pulls the leg backwards powerfully for walking and running. What is the biggest muscle in the body? Answer: The G luteus Maximus The Gluteus Maximus is located in the buttock. It is only 5mm long and thinner than cotton thread. What is the smallest muscle in the body? Answer: The S tapedius The Stapedius is located deep in the ear.
What is the longest muscle in the body? Answer: The S artorius The Sartorius runs from the outside of the hip, down and across to the inside of the knee. TRIVIA! How many muscles are there in the human body? Answer: 640 Muscles The muscles make up about 40 % of the body mass. The Muscular System Specialized tissue that enable the body and its parts to move.