| Question | Answer |
| The ability of skeletal muscle to shorten with force | Contractility |
| The capacity of skeletal muscle to respond to a stimulus | Excitability |
| Extensibility | The ability to be stretched |
| Ability to recoil to their original resting length after they have been stretched | Elasticity |
| Each skeletal muscle is surrounded by a connective tissue sheath called | The epimysium |
| ______ is another connective tissue located outside the epimysium | Fascia |
| The fasciculi are composed of single muscle cells called ______ | Fibers |
| Each fiber is surrounded by a connective tissue sheath called the | Perimysium |
| A threadlike structure that extends from one end of the fiber to the other | Myofibrils |
| Thin myofilaments | Actin myofilaments |
| Thick myofilaments | Myosin myofilaments |
| Actin and myosin myofilaments form highly ordered units called | Sarcomeres |
| What band extends the length of the myosin | The A band |
| On each side of the Z line is a light area called | I band |
| The change difference across the membrane is called the | Resting membrane potential |
| The brief reversal back of the charge is called | Action potential |
| Nerve cells that carry action potentials to skeletal muscle fibers | Motor neurons |
| Each branch that connects to the muscle forms | Neuromuscular junction |
| A single motor neuron and all the skeletal muscle fibers it innervates are called | A motor unit |
| The enlarged merger terminal | Presynaptic terminal |
| Space between the presynaptic terminal and the muscle cell is the | Synaptic cleft |
| Each presynaptic terminal contains | Synaptic vesicles |
| A contraction of the entire in response to a stimulus that causes the action potential in on of more muscle | Muscle twitch |
| The time between application of a stimulus to a motor neuron and the beginning of a contraction is the | Lag phase |
| The time of contraction is the | Contraction phase |
| The time during which the muscle relaxes is the | Relaxation phase |
| Where the muscle remains contracted without relaxing | Tetany |
| The increase in number of motor units being activated is called | Recruitment |
| ATP | Adenosine Triphosphate |
| ATP | is needed for energy for muscle contraction |
| ATP | Is produced in the mitochondria |
| ATP | Is short lived and unstable |
| Muscles that work together to accomplish specific movements are | Synergists |
| Muscles that work in opposition to one another are called | Antagonists |
| Most stationary end of the muscle | Origin (head) |
| The end of the muscle undergoing the greatest movement | Insertion |
| Portion of the muscle between the origin and the insertion is the | Belly |
| Some muscles have multiple | Origins or heads |
| 2 types of muscle contractions | Isometric & isotonic |
| Anaerobic respiration | Without oxygen |
| Aerobic respiration | With oxygen (more efficient) |
| If one muscle plays the major role in accomplishing the desired movement, it is the | Prime mover |
| Mastication | Chewing |
| 4 pairs of mastication muscles | 2 pairs of pterygoids, temporalis, and masseter |
| Intrinsic tongue muscles | Change the shape of the tongue |
| Extrinsic tongue muscles | Move the tongue |
| Sternocleidomastoid | Lateral neck muscle and prime mover |
| Platysma | Sheetlike muscle that covers the anterolateral neck |
| Occipitofrontalis | Raises the eyebrows |
| Orbicularis oculi | Closes the eyelids (causes crows feet) |
| Orbicularis oris | Puckers the lips |
| Buccinator | Flattens the cheeks |
| Zygomaticus | Smiling muscle |
| Levator labii superioris | Sneering |
| Depressor Anguli oris | Frowning |
| Group of muscles on each side of the back | Erector spinae |
| External intercostals | Elevate the ribs during inspiration |
| Internal intercostals | Contract during forced expiration |
| Ok each side of the linea alba is the ______ ________ muscle | Rectus abdominis |
| Scapular movements: | Trapezius & serratus anterior |
| Trapezius | Rotates scapula |
| Serratus anterior | Pulls scapula anteriorly |
| Pectoralis major | Adducts and flexes the arm |
| Latissimus dorsi | Medially rotates, adducts, & powerfully extends the arm "swimmer muscles" |
| Deltoid | Attaches the humerus to the scapula and clavicle |
| Triceps brachii | Extends the forearm |
| Biceps brachii | Flexes the forearm |
| Brachialis | Flexes forearm |
| Brachioradialis | Flexes and supinates the forearm |
| Flexor carpi | Flexes the wrist |
| Extensor carpi | Extends the wrist |
| Flexor digitorum | Flexes the fingers |
| Extensor digitorum | Extends the fingers |
| 19 hand muscles | Intrinsic hand muscles |
| Gluteus maximus | Buttocks |
| Quadriceps femoris | Extends the leg |
