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Muscles
Anatomy
Question | Answer |
---|---|
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 stretched. | Extensibility |
Ability to recoil to their original resting length after they have been stretched. | Elasticity |
Nerve cells that carry action potentials to skeletal muscle fibers | Motor neurons |
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 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 | Relaxation phase |
Where the muscle remains contracted without relaxing | Tetany |
Contract quickly and fatigue quickly. well adapted to perform anaerobic metabolism. ex. white meat of a chickens breast. | Fast twitch fibers |
Contract more slowly and are more resistant to fatigue. They are better suited for aerobic metabolism. Ex. dark meat of a ducks breast or legs of a chicken. | slow twitch fibers |
Without oxygen | anaerobic respiration |
With oxygen | Aerobic respiration |
Results when ATP is used during muscle contraction faster than it can be produced in the muscle cells. | Muscle fatigue |
Constant tension produced by muscles of the body for long periods of time. Keeps head up and back straight. | Muscle tone |
(equal distance) The length of the muscle does not change, but the amount of tension increases during the contraction process. | Isometric |
(equal tension) The amount of tension produced by the muscle is constant during contraction, but the length of the muscle changes. | Isotonic |
The most stationary end of the muscle. | Origin |
The end of the muscle undergoing the greatest movement. | Insertion |
The portion of the muscle between the origin and the insertion. | Belly |
Muscles that work together to accomplish specific movements. | Synergists |
Muscles that work in opposition to one another. | Antagonists |
Among a group of synergists, if one muscle plays the major role in accomplishing the desired movement it is the | Prime mover |
raises the eyebrows | Occipitofrontalis |
closes the eyelids and causes "crows feet" wrinkles in the skin at the lateral corners of the eye. | Orbicularis oculi |
Puckers the lips. | Orbicularis oris |
flattens the cheeks. | Buccinator |
The kissing muscles | Trumpeters muscle, Orbicularis oris, and Buccinator. |
Smiling muscle | Zygomaticus |
Sneering muscle | Levator labii superioris |
Frowning muscle | Depressor anguli oris |
4 pairs of mastication muscles | 2 pair of pterygoids, temporalis, and masseter. |
Changes the shape of the tongue | Intrinsic tongue muscles |
Moves the tongue | Extrinsic Tongue Muscles |
Lateral neck muscle and prime mover. Rotates and abducts the head. | Sternocleidomastoid |
Group of muscles on each side of the back. Responsible for keeping the back straight and body erect. | Erector spinae |
Muscles that move the thorax. | Thoracic muscles |
Elevates the ribs during inspiration. | External intercostals |
Contracts during forced expiration. | Internal intercostals |
Accomplishes quiet breathing. Dome shaped muscle. Aids in breathing. | Diaphragm |
On each side of the linea alba is the | Rectus abdominis |
Crosses the rectus abdominis at three or more locations, causing the abdominal wall of a well muscled person to appear segmented. | Tendinous inscriptions |
These muscles flex and rotate the vertebral column, compress the abdominal cavity, and hold in the abdominal viscera. | Abdominal wall muscles |
Rotates scapula | Trapezius |
Pulls scapula anteriorly | Serratus anterior |
What are the scapula movements | Trapezius, Serratus anterior |
The arm is attached to the thorax by the | Pectoralis major and Latissimus dorsi muscles |
Adducts and flexes the arm | Pectoralis major |
Medially rotates, adducts, and powerfully extends the arm. "Swimmer muscles." | Latissimus dorsi |
Attaches the humerus to the scapula and clavicle, and is the major abductor of the upper limb. | Deltoid |
Extends the forearm. Occupies the posterior compartment of the arm. | Triceps brachii |
Flexes the forearm. Occupies the anterior compartment of the arm. | Biceps brachii |
Flexes forearm | Brachialis |
Flexes and supinates the forearm | Brachioradialis |
Forearm movements | Triceps brachii, Biceps brachii, Brachialis, Brachioradialis |
String band of fibrous connective tissue that covers the flexor and extensor tendons and holds them in place around the wrist so they do not "bowstring" during muscle contraction. | Retinaculum |
Flexes the wrist | Flexor carpi |
Extends the wrist | Extensor carpi |
Flexes the fingers | Flexor digitorum |
extends the fingers | extensor digitorum |
What are the 19 hand muscles called | Intrinsic hand muscles |
What muscles are located between the metacarpals | Interossi muscles |
These muscles are responsible for abduction and adduction of the fingers | Interossi muscles |
Buttocks. | Gluteus maximus |
Extends the leg; anterior thigh muscles | Quadriceps femoris |
"Tailors muscle;" flexes the thigh | Sartorius |
posterior thigh muscles; flexes the leg and extends the thigh. | Hamstring muscles |
lateral muscles of the leg | Peroneus muscles |
how many muscles are located within the foot | 20 |
What muscles flex, extend, abduct, and adduct toes | Intrinsic foot muscles |
The charge difference across the membrane is called | Resting membrane potential |
A single motor neuron and all the skeletal muscle fibers it innervates are called | Motor unit |
The sliding of actin myofilaments past myosin myofilaments during contraction is called the | Sliding filament mechanism |
A muscle fiber will not respond to stimulus until that stimulus reaches a level called | Threshold |