| Question | Answer |
| What is the ability of skeletal muscle to shorten with force? | Contractility |
| The capacity of skeletal muscle to respond to a stimulus. | Excitability |
| The ability to be streched | Extensibility |
| Ability to recoil to their original resting place after they have been streched. | Elasticity |
| Connective tissue sheath that surrounds each skeletal muscle | epimysium |
| Connective tissue located outside the epimysium. Surrounds and seperates muscles. | Fascia |
| Visible bundles that compose the muscle | Fasciculi (Fascicle) |
| Loose connective tissue that surrounds the fasciciles. | Perimysium |
| Muscle Cells | Fibers |
| Connective tissue sheath surrounding each fiber | endomysium |
| A threadlike structure that extends from one end of the fiber to the other. | Myofibrils |
| Thin myofilaments | Actin Myofilaments. |
| Thick myofilaments | Myosin Myofilaments |
| Units joined end to end forming the myofibril | Sarcomere |
| Basic structural and functional unit of the muscle | Sarcomere |
| Attachment site for Actin | Z Line |
| Light area on each side of the Z Line consisting of actin | I Band |
| Darker central reigon of the sarcomere | A Band |
| Light area in the center of each sarcomere consisting of only myosin | H Zone |
| Center of the sarcomere, a dark staining band | M Line |
| Charge difference across the membrane | Resting membrane potential |
| The brief reversal back of the charge in a cell | Action Potential |
| nerve cells that carry action potentials to skeletal muscle fibers | Motor neurons |
| Each branch that connects to the muscle | Neuromuscular Junction or Synapse |
| 25. A single motor neuron and all the skeletal muscle fibers it innervates | Motor unit |
| Enlarged nerve terminal | Presynaptic Terminal |
| The space between the presynaptic terminal and the muscle cell | synaptic cleft |
| Muscle Fiber | Postsynaptic Terminal |
| Secretes a neurotransmitter called acetylcholine | Synaptic Vesicles |
| Neurotransmitter secretion from the synaptic vesicles | acetylcholine |
| Enzymes that break down the the acetylcholine | Acetylcholineterase |
| The sliding of actin myofilaments past myosin myofilaments during contraction | sliding filament mechanism |
| A contraction of an entire muscle in response to a stimulus that causes the action potential in one or more muscle fibers | Muscle twitch |
| The level at which the muscle fiber will contract maximally | Threshold |
| The phenomenon in which the muscle fibers contrzct maximally | All-or-none response |
| The time between application of a stimulus to a motor neuron and the beginning of a contraction | Lag phase |
| The time of contraction | contraction phase |
| The time during which the muscle relaxes | The relaxation phase |
| Where the muscle remains contracted without relaxing | tetany |
| The increase in number of motor units being activated is called ________ | Recruitment |
| Needed energy for muscle contraction | ATP |
| Produced in mitochondria | Atp |
| 43Shortlived and unstable. Dengenerates to _____ plus phosphate | ADP |
| High energy stored molecule stored at rest | creatine phosphate |
| 45. Without oxygen | Anaerobic respiration |
| 46. With oxygen | Aerobic Respiration |
| 47.The amount of oxygen needed in chemical reactions to convert lactic acid to glucose and to replenish the depleted stores of creatine phosphate stores in muscle cells. | Oxygen Debt |
| Results when ATP is used during muscle contraction faster than it can be produced in muscle cells. | Muscle Fatigue |
| The length of the muscle does not change, but the amount of tension increases during the contraction process. | Isometric |
| 50. The amount of tension produced by the muscle is constant during contraction, but the length of the muscle changes. | Isotonic |
| Constant tension produced by the muscles of the body for long periods of time. | Muscle tone |
| Contract quickly and fatigue quickly. | Fast-twitch fibers |
| Contract more slowly and are more resistant to fatigue. They are better suited for aerobic metabolism. | Slow twitch fibers |
| The most stationary end of a muscle | Origin (head) |
| The end of the muscle undergoing the greatest movement. | Insertion |
| The portion of the muscle between the origin and the insertion. | The belly. |
| Muscles that work together to accomplish specific movements | Synergists |
| Muscles that work in opposition to one another | antagonists |
| One muscle that plays the major role in accomplishing the desired movement | Prime Mover |
| 60.Occiptofrontalis | Raises eyebrows |
| Orbicularis Oculi | closes eyelids |
| Orbicularis Oris | Puckers Lips |
| Buccinator | Flattens the Cheek |
| Zygomaticus | Smiling |
| Leviotao Labii Superiortis | Sneering |
| Depressor Anguli Oris | Frowning |
| Mastication | The act of chewing |
| Muscles involved in chewing: | Buccinator, Temporalis, & Masseter |
| Extrinsic Toungue Muscles | Move the tounge |
| Intrinisic Toungue Muscles | Change the shape of the tounge |
| Prime Mover; Lateral Neck Muscle | Sternocleidomastoid |
| Muscle on each side of the vertebral column | Erector Sprine |
| Elevates ribs during inspiration | External Intercostals |
| Contrasts during forced expiration | Internal Intercostals |
| Dome shaped muscle that seperates thoracic cavity from abdominopelvic cavity | Diaphram |
| How are muscles named? | Location, size, orientation of fibers, shape, origin, insertion, and function. |
| Which part of the muscle undergoes the greatest movement? | Insertion |
| Which part of the muscle is most stationary? | Origin;Head |
