Question | Answer |
What does Skeletal Muscle do and how is it controlled? | controlled by the conscious mind and moves the bones of the skeleton so the animal can move around |
What does Cardiac Muscle do and how is it controlled? | found only in the heart and it starts the heart beating long before an animal is born and keeps it up until the animal dies, under involuntary control |
Where is Smooth Muscle found and what does it do? | found all over the body like the eyes, air passageways, GI tract, bladder, blood vessels and reproductive tract; carries out most of the internal movements that the body needs to maintain itself in good working order; involuntary control |
Which type of muscle has Multiple Cell Nuclei? | Skeletal Muscle |
What are the Cell Shapes for each type of muscle? | Skeletal- long thin fibers
Cardiac- branched
Smooth- spindle |
What do Tendons do? | attach muscle to bone |
What are Aponeuroses? | broad sheets of fibrous connective tissue that connect muscle to bone or muscle to other muscles |
Where is the Origin of the Muscle? | the muscle's attachment site that is more stable and moves less than the other, it does not move much when the muscle contracts |
Where is the Insertion of the Muscle? | the site that undergoes most of the movement when a muscle contracts |
What is a Prime Mover or Agonist? | a muscle or muscle group that directly produces a desired movement |
What is the Antagonist? | a muscle or muscle group that directly opposes the action of a prime mover |
What is a Synergist? | a muscle that contracts at the same time as a prime mover and assists it in carrying out its action |
What do Fixator Muscles do? | stabilize joints to allow other movements to take place |
What is a Sarcolemma? | muscle cell membrane |
What is a Sarcomere? | basic contracting unit of skeletal muscle |
What are Neuromuscular Junctions? | sites where the ends of motor nerve fibers connect to muscle fibers |
What is the All or Nothing Principal? | an individual muscle fiber either contracts completely when it receives a nerve impulse or it does not contract at all |
What is Myoglobin? | its like hemoglobin for muscles, it can store and release large quantities of oxygen |
Describe the Structure of Muscles | Groups of Myofilaments make up a Myofibril. Groups of Myofibrils make up a Muscle Fiber which is also the called the Muscle Cell, and groups of these make are called Fascicles and make up a muscle |
Describe the Connective Tissue Layers of Muscle: | Groups of muscle fascicles are surrounded by Epimysium and each individual fascicle is bound together by Perimysium, each individual fiber within the fascicle is surrounded by Endomysium |
What is the A Band? | made of thick Myosin filaments |
What is the I Band? | made of thin Actin filaments |
What is the Z Line? | dark line in the center of the I band, it is the attachment site for the actin filaments |
What is a Sarcomere? | the area from one Z line to the next Z line |
What is a Motor Unit? | one nerve fiber and all the muscle fibers it innervates |
What do Cross Bridges do? | when stimulated to contract, small levers that ratchet back and forth and pull the actin filaments on both sides toward the center of the myosin filaments |
What is Aerobic Metabolism? | as long as the oxygen supply is adequate to keep up with the energy needs of the fiber and the maximum amount of energy is extracted from each glucose fiber |
What is Anaerobic Metabolism? | the need for oxygen exceeds the available supply and muscle fibers must shift to non oxygen dependent metabolism to produce the energy required for continued activity |
What is Lactic Acid? | a by product of incomplete glucose breakdown resulting from anaerobic metabolism, it can accumulate in the muscle tissue and cause discomfort |
What does Creatine Phosphate do?s | its the "battery charger" that converts ADP back to ATP |
What are Intercalated Disks? | fasten the cells together and transmit impulses from cell to cell to allow large groups of cardiac muscle cells to contract in a coordinated manner |