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Chapter 6 Stack
Muscles
Question | Answer |
---|---|
Four major functional characteristics of muscles | Contractility, excitability, extensibility, elasticity |
Connective tissue sheath around each skeletal muscle | Epimysium |
Connective tissue sheath surrounding each muscle fiber | Endomysium |
Basic structural unity of the muscle | Sarcomere |
Z line (disc), I band, A band, H zone, M line | Make up a sarcomere |
Acetylcholine | Neurotransmitter |
Acetylcholinesterase | Breaks down Acetylcholine |
Muscle twitch | A contraction of an entire muscle in response to a stimulus |
Lag phase | The time between the application of a stimulus to a motor neuron and the beginning of a contraction |
Contraction phase | Time of contraction |
Relaxation phase | Time during which the muscle relaxes |
Tetany | Where the muscle remains contracted without relaxing |
Recruitment | The increase in number of motor units being activated |
Anaerobic Respiration | Without oxygen |
Aerobic Respiration | With oxygen |
Muscle fatigue | Results when ATP is used during muscle contraction faster than it can be produced |
Isometric | (Equal Distance) length of the muscle does not change |
Isotonic | (Equal Tension) amount of tension dows not change |
Fast-twitch/slow-twitch | Contract quickly and fatigue quickly/contract slowly and are more resistant to fatigue |
Origin, Insertion, and Belly | Stationary end of the muscle, end of the muscle undergoing the greatest movement, and the portion of the muscle in the middle |
Synergists and Antagonists | Muscles that work together and muscles that work in opposition |
Occipitofrontalis | Raises Eyebrows |
Orbicularis Oculi | Closes eyelids |
Orbicularis Oris | Puckers lips |
Buccinator | Flattens cheeks |
Zygomaticus | Smiling muscle |
Levator Labii Superoris | Sneering muscle |
Depressor Anguli Oris | Frowning muscle |
Mastication (chewing muscles) | Temporalis, Masseter, and two pairs of pterygoids |
Two types of tongue muscles | Intristic and Extrinsic |
Intristic tongue muscles | Changes the shape of the tongue |
Extrinsic tongue muscles | Moves tongue |
Neck muscle that rotates and extends the head | Sternocleidomastoid |
Torticollis | Twisted neck; wry neck |
Nomenclature | Muscles that have names that are descriptive according to their location, size, orientation of fibers, shape, origin, insertion, and function. |
Muscles that move the vertebral column | Erector Spinae |
Thoracic muscles | Muscles that move the thorax |
Muscles involved in breathing | External intercostals – elevate the ribs during inspiration. Internal intercostals – contract during forced expiration |
Diaphragm | Dome shaped muscle that accomplishes quiet breathing |
Linea Alba | Tendinous area of the abdominal wall consisting of white connective tissue |
Rectus Abdominus | Muscle on each side of the linea alba |
Tendinous Inscriptions | Cross the rectus abdominus at three or more different locations |
Scapular movements | Trapezius and Serratus Anterior |
Trapezius | Rotates scapula |
Serratus Anterior | Pulls scapula anteriorly |
Arm movements | Pectoralis major, latissimus dorsi, deltoid |
Pectoralis major | Adducts and flexes the arm |
Latissimus dorsi | Medially rotates, adducts, and powerfully extends the arm (swimmers muscles) |
Deltoid | Attaches the humerus to the scapula and clavicle |
Forearm movements | Triceps brachii, Biceps branchii, Brachialis, Brachioradialis |
Triceps branchii | Extends the forearm; occupies the posterior compartment of the arm |
Biceps branchii | Flexes the forearm; occupies the anterior compartment of the arm |
Brachialis | Flexes forearm |
Brachioradialis | Flexes and supinates the forearm |
Wrist and finger movements | Retinaculum (bracelet, Flexor carpi, Extensor carpi, Flexor digitorum, Extensor digitorum |
Retinaculum (bracelet) | Strong band of fibrous connective tissue that covers the flexor and extensor tendons and holds them in place around the wrist |
Flexor carpi | Flexes the wrist |
Extensor carpi | Extends the wrist |
Flexor digitorum | Flexes the fingers |
Extensor digitorum | Extends the fingers |
Intrinsic hand muscles | 19 muscles located in the hand |
Interossi muscles | Located between the metacarpals, are responsible for abduction and adduction of the fingers |
Thigh movements | Gluteous Maximus, gluteous minimus |
Gluteous Maximus | Buttocks |
Gluteous Minimus | Hp muscle and common injection site |
Leg movements | Hamstring muscles |
Hamstring muscles | Posterior thigh muscles |
Ankle and Toe movements | Gastrocnemius and soleus |
Gastrocnemius and Soleus | Form the calf muscle; join to form the calcaneal tendon (Achilles tendon); flex the foot and toes |
Peroneus muscles | Everters; aid in plantar flexion; lateral muscles of the leg |
Intrinsic foot muscles | Flex extend, abduct, and adduct the toes |
Lower limb consists of | Gluteous maximus, gluteous minimus, quadriceps femoris, sartorius, hamstring, gastrocnemius and soleus |
Trunk muscles | Erector spinae, thoracic muscles, external and internal intercostals, rectus abdominus, and diaphragm |
Biceps femoris | Posterior leg muscles |
Rectus femoris | Anterior leg muscles |