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193 Cards in this Set
- Front
- Back
The term myo refers to ________.
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Muscle
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Sacro refers to ___________ _______.
At the cellular level the, the cytoplasm of a muscle cells is called the _____________. |
Muscle Cells
Sarcoplasm |
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Myology is the study of ___________ and myositis is _______________ of the muscle.
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Muscles
Inflammation |
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In general the nervous system gives the orders and the muscular system ____________.
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Carries them out.
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What is it called when a muscle cell gets smaller? When it gets larger?
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Atrophy
Hypertrophy |
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What is it called when a muscle cell increase in size due to the increase in the number of cells?
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Hyperplasia
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What is the term for when a muscle cell has a change in the structure of the cell?
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Metaplasia
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Skeletal muscle ___________ the bones of the skeleton, which in turn ___________ the animal around.
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Move
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Skeletal muscle is often referred to as ____________ muscle.
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Voluntary Striated
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It is called voluntary because it is ____________.
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Under the control of the conscious mind.
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The number of muscle fibers that are stimulated to contract is what?
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Strength of Contraction
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What is the thick central portion of the muscle called?
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Belly
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Most muscle attach to bones at both ends by though, fibrous connective tissue bands called __________.
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Tendons
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Some muscles are attached by broad sheets of fibrous connective tissue called ___________.
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Aponeuroses
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The prominent aponeuroses is the ___________ that runs lengthwise between the muscles on the animal's ventral midline.
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Linea Alba
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One of the muscle's attachment sites is generally more stable then the other, this more stable site is called the _________ of the muscle.
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Origin
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The site that undergoes most of the movement when a muscle contracts is called the ____________.
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Insertion
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When stimulated by a nerve impulse a muscle _____________.
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Contracts (shortens)
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What term is used to describe a muscle or muscle group that directly produces a desired movement?
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Prime Mover
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What is a muscle or muscle group that directly opposes the action of a prime mover?
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Antagonist
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What is a muscle that contrasts at the same time as a prime mover and assists it in carrying out its actions?
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Synergist
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What is a muscle that stabilizes joints to allow other movements to take place?
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Fixator
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Which muscle occurs in the superficial fascia between the skin and the deep fascia covering the skeletal muscles.
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Cutaneous Muscles
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Cutaneous Muscles are thin and just serve to _______ the skin. Who has the thickest cutaneous muscle, horse or cat?
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Twitch
Horse |
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The most obvious function of the abdominal muscles it to ___________. What are some of their other functions?
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Support the abdominal organs, Help flex the back, Assist in various functions of straining (expulsion of feces, urine, and newborn), and in the process of vomiting and regurgitation.
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Name the abdominal muscles from outside in.
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External Abdominal Oblique
Internal Abdominal Oblique Transversus Abdominis Rectus Abdominis |
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Which abdominal muscle's fibers runs in a caudo-ventral oblique direction?
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External Abdominal
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Which abdominal muscle's fibers run in a cranio-ventral direction?
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Internal Abdominal
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Which muscle consist of two strap like muscles that run from the ribs and sternum back to the brim of the pubis?
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Rectus Abdominis
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Which is the deepest muscle whos fibers run directly downward in a ventral direction?
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Transversus Abdominis
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The muscles of the thoracic limb function mainly in ____________.
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Locomotion
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Name the muscles of the extrinsic thoracic limb.
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Latissimus Dorsi, Pectoral muscle, Deltoids, Brachiocephalicus, Omotransversarius, Trapezius, Rhomboideus, and Serratus Ventralis.
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The latissimus dorsi muscle a broad triangular muscle extends from the _____ to its insertions on the ___________.
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Spinal Column
Humerus |
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What are the 4 pectoral muscles?
They extend from the _______ to the _________, and act as _______ of the front limb. |
Descending Superficial Pectoralis, Transverse Superficial Pectoralis, Deep Pectoral, and Xiphihumeralis.
Sternum to Humerus Adductors |
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What are the 2 deltoids?
They extend from the _____ to the ________. These muscles _____ and _________ the shoulder joint. |
Spinodeltoid and Acromiodeltoid
Scapula to humerus Abduct and Flex |
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What are the 2 heads of the brachiocephalicus?
Their action is to _____ the limb forward and _____ the shoulder. |
Cleidocephalicus and Cleidobrachialis
pull and extend |
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The cleidocephalicus extends from the ____ to the _____.
The cleidobrachialis extends from the _____ to the _____. |
Skull to Clavicle tendon
Clavicle tendon to Humerus |
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Which muscle is not present in horses?
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Omotransversarius
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The omotransversarius extends from the __________ to the _______. Its action is to ___________ the limb.
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Wing of Atlas
Scapula Advance |
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The trapezius extends from the _______ to the _______.
Its action is to _______ and ________ the forelimb. |
Atlas to Thorax
Elevate and Abduct |
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The Rhomboideus has 3 heads, name them.
Their action is the _______ the forelimb. They are shaped like a ________ facing up. |
Rhomboideus capitis, Rhomboideus cervicis, and Rhomboideus thoracis.
Elevate Fan |
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Rhomboideus Capitis extends from the _______ to the __________.
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Occipital bone to the Scapula
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Rhomboideus Cervicis extends form the ________ to the _______.
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Cervical Vertebrae to the Scapula
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Rhomboideus Thoracis extends from the ______ to the _______.
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Thoracic Vertebrae to the Scapula
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Serratus Ventralis extend from the _______ to the ________, and its action is to _______ the trunk. It is shaped like a ______ facing down.
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Cervical Vertebrae to the Scapula
Fan |
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What is the most powerful of the chewing muscles?
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Masseter
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The muscles of the neck help support the head and allow the head and neck to _____, _________, and _________.
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Flex, Extend, an move laterally.
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2 of the main muscles that extend the head and neck are the __________ and the ___________.
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Splenius and Trapezius
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Another muscle that extends the head and neck and also pulls the front leg forward is the _________ muscle.
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Brachiocephalic
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The sternocephalic muscle extends form the ________ to the ________ and acts to ________ the head and neck.
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Sternum to the base of skull
Flex |
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The masseter extends from the ______ to the ________, and its action is to ________.
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Zygomatic arch to the mandible
Elevate mandible when chewing |
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The temporalis muscle extend from the _______ to the ________, and its action is to ___________.
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Parietal, temporal, frontal, and Occipital bone to the mandible.
Elevates mandible for chewing and moves it laterally, |
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Which muscle forms along with the brachiocephalicus, the jugular groove.
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Sternocephalicus
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The sternocephalicus extends from the ______ to the __________ and its action is to ___________.
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Sternum to the occipital bone
Depress and draws the head and neck to the side |
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Which muscle helps the cat to smile?
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Platysma
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The platysma muscle extends from the ___________ to the __________, and its action is to __________.
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Cervical Vertebrae to the fibers around the lips
Draw the commissures of the lips caudally |
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The infraspinous muscle extends from the _________ to the __________ and its action is to ________ the shoulder joint and _________ the limb at the shoulder.
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Scapula to the humerus
Flexes and Abducts |
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The deltoids are an aginist with which other lateral muscle of the shoulder?
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Infraspinous
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The supraspinatus extends from the ___________ to the __________ and its action is to _______ the shoulder joint.
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Suprespinous fossa to the humerus
Extend |
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Which other lateral shoulder muscle is an antagonist with the supraspinatus muscle?
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Infraspinous Muscle
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The subscapularis muscle extends from the ___________ to the _________ and its action is to __________ the limb at the shoulder and ________ the leg medially.
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Scapula to the humerus
Adducts and Rotates |
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The teres major muscle extends from the ______ to the ______. Its action is to ________ the shoulder.
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Scapula to the humerus
Flexes |
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The biceps brachii extends from the ________ to the ____________. Its action is to _______ the elbow and ________ the shoulder.
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Scapula to the ulnar and radial tuberosities
Flex and extend |
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Brachialis muscle extends from the ________ to the ___________, and its action is to ______ the elbow.
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Humerus to the ulnar and radial tuberosities
Flex |
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Triceps Brachii muscle has 3 heads _________, _________, and _______ in most animals but carnivores have a 4th head called the _________ head.
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Long, Medial, and Lateral
Accessory |
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The long head of the triceps brachii begins at the ______, the others have a common origin of ______ and they all insert on the ______. Its action is to ______ the elbow and _____ the shoulder.
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Scapula / Humerus to the ulna
Extend and Flex |
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The two primary antagonistic set of muscles in the limb is the ________ and the _________.
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Quads and the Hamstrings
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The large gluteal muscles and the hamstring muscle group are ________ muscles of the hip joint.
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Extensor
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What are the 3 hamstring muscles located on the back of the thigh region?
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Biceps Femoris, Semimembranosus, and Semitendinousus.
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What are their origins and insertions?
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Origin (All) - Ischiatic Tuberosity
Insertion - Biceps = Patella/Tibia Semimem = Femur Semitend = Tibia |
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What are their actions?
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Action - All extend hip and Flexes the stifle, Biceps and Semitend also extends the tarsal joint
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What are the 4 quadriceps muscles?
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Rectus Femoris, Vastus Lateralis, Vastus Intermedius, Vastus Medialis
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What are their origins, insertions, and actions?
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Origin - Rectus = Ilium, The rest = Femur
Insertion (All) - Tibial Tuberosity Action (All) - Extends the stifle joint and flexes the hip. |
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The tensor fasciae latae extends from the ________ to the ________ and its action is to_______ the hip joint and _______ the stifle.
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Ilium to the Femoral Fascia
Flexes and Extends |
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What is the tendon that is commonly used by surgeons to make cuts and strips to replace the anterior cruciate ligament during repair?
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Fasciae Latae
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Superficial Gluteal Muscle extends from the _______ to the ________ and its action is to ________ the limb and ________ the hip.
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Sacrum and Coccygeal Vertebrae to the femur
Abduct and Extend |
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Middle Gluteal Muscle extend from the ______ to the ______. Its action is to ________ the limb and ________ the hip.
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Ilium to Femur
Abducts and Extends |
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Deep Gluteal Muscle extends from the ______ to the __________. Its action is to _______ and _______ the hip.
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Ilium and Ischiatic Spine to the Greater Trochanter
Abducts and Extends |
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What is the longest and widest of the thigh muscles?
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Biceps Femoris Muscle
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Biceps Femoris extends from the ________ to the _______, and its action is to ______ the hip, ________ the stifle, and ______ the hock.
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Pelvis to the patella, tibia, and tuber calcanei
Extends, Flexes, and Extends |
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Semitendinosus muscle extends from the ________ to the _______ and its action is to _______ the hip, ________ the stifle, and to ________ the tarsal joint.
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Ischiatic Tuberosity to the tibia and tuber calcanei
Extend, Flexes, and Extends |
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Semimembranosus Muscle extends from the ______ to the ______, and its action is to _________ the hip, and _______ the stifle
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Ischiatic Tuberosity to the femur and tibia
Extend and Flexes |
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Sartorius Muscle extends from the ________ to the ________ and its action is to _______ the hip, _______ the stifle, and ________ the stifle.
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Ilium to the patella and tibia
Flexes, Extends, and Flexes |
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Gracilis Muscle extends from the ______ to the _______ and its action is to _____ the limb, _______ the stifle, and ______ the hip and hock.
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Pelvic Symphysis to the tibia and tubercalcanei
Adducts, Flexes, and Extends |
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Which muscle is severed to relieve pain in dogs with chronic hip dysplasia?
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Pectineus Muscle
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Pectineus muscle extends from the ________ to the _______ and its action is to ______ the limb.
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Prepubic Tendon to the femur
Adduct |
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The adductor muscle consists of 2 muscles, name them.
Which is larger and which is smaller? |
Adductor Magnus - Larger
Adductor Longus - Smaller |
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The adductor muscle extends from the _______ to the ______ and its action is to _______ the limb and to _______ the hip.
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Pelvic Symphysis to the Femur
Adduct and Extend |
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Cranial Tibial Muscle extends from the ______ to the _______ and its action is to _______ the tarsal joint.
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Cranial Tibial Border to the metatarsus
Flexes |
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Long Digital Extensor Muscle extends from the ______ to the _______ and its action is ________ the digital joints, ______ the tarsal joint, and _______ the stifle joint.
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Femur to the distal phalanges
Extends, Flexes, and Extends |
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Peroneus Longus muscle extends from the _______ to the _______ and its action is to _______ the tarsal joint.
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Tibia and Fibula to the metatarsals
Flex |
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Gastrocnemius muscle extends from the _______ to the _______ and its actions is to ______ the tarsus and _____ the stifle.
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Femur to the tuber calcanei
Extend and Flexes |
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Deep Digital Flexor muscles extend from the ________ to the _______ and its action is to _______ the tarsal joints, and ________ the digital joints.
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Fibula to the phalanges
Extend and Flexes |
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Popliteus muscle extends from the _______ to the _______ and its action is to ________ the stifle and _______ the leg medially.
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Femur and Tibia
Flexes and Rotates |
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What is the common name for the Common Calcanean Tendon? Where does it insert? What 5 muscles is it made up of?
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Achilles Tendon
Tuber Calcanei Gastrocnemius, Superficial digital flexor, Semitendinosus, Gracilis, and Biceps Femoris |
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The muscles that increase the size of the thoracic cavity when they contract are called __________ muscles.
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Inspiratory
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What are the 2 main inspiratory muscles?
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Diaphragm and the external intercostal muscles.
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What is the thin, dome-shaped sheet of muscle that separates the thoracic cavity from the abdominal cavity?
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Diaphragm
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What happens to the diaphragm when the animal breathes in? out?
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In = Flattens out
Out = Pushes up / becomes convex |
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The external intercostal muscle fibers are directed in a ________ direction so they can contract, and _______ the ribs upward and forward.
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Oblique
Rotate |
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Why does expiration not require as much effort as inspiration?
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Because of mechanical forces, like gravity, and the elastic nature of the lungs help collapse the rib cage and push air out.
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What are the 2 sets of expiratory muscles that aid in the process?
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Internal intercostal muscles, and Abdominal Muscles.
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The internal intercostal muscles run at ________ to those of the external. When these contract, the ______ the ribs backward, which _______ the size of the thorax.
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Right Angles
Rotate Decreases |
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Adbominal Muscles simply ________ reducing the space of the peritoneal cavity.
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Contract
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Name the 4 heads of the abdominal muscles?
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External Abdominal Oblique
Transversus Abdominis Internal Abdominal Oblique Rectus Abdominis Muscle |
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Skeletal Muscles are usually called skeletal muscle fibers due to their overall ___________ shape.
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Threadlike or fiber-like shape
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A system common to skeletal muscles only allow for the transport of impulses and nutrients from the ______ the muscle down to the __________.
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Outside
Protein Filaments |
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Transverse or T tubules extend from the _________ down to the _________.
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Sarcolemma to the protein filaments
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The miofibrils that make up the muscle fiber are composed of thousands of tiny, contractile protein filaments known as the _______ and _______ filaments.
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Actin and Myosin
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The dark line in the center of the I band is called the ___________.
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Z Band
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The area from one Z line to the next Z line is called a ____________.
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Sarcomere
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What is the basic contraction unit of skeletal muscle?
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Sarcomere
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Each of the __________ is made up of many sarcomere lined up end to end.
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Myofibrils
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What is suprascapular nerve - to muscles innervation, supraspinous and infraspinus muscles.
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Sweeny
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The sites where the ends of motor nerve fibers "connect" to muscle fibers are called __________ ____________.
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Neuromuscular Junctions
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If a skeletal muscles nerve supply is interrupted for a lengthy period as a result of injury, the muscle will shrink down through a process called ___________.
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Atrophy
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Within the end of the nerve fiber in a neuromuscular junction are tiny sacs called _________ _________ that contain the chemical neurotransmitter ____________.
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Synaptic Vesicles
Acetylcholine |
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The effect of the acetylcholine on its receptor is very _______ lasting.
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Short
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An enzyme in the synapse space called _____________, quickly removes the acetylcholine molecule from its receptor and splits it apart.
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Acetylcholinesterase
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The number of muscle fibers per nerve fiber determines what?
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How small a movement will result from a nerve stimulus
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What is the term to describe one nerve fiber and all the muscles fibers it innervates?
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Motor Unit
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Each individual skeletal muscle fiber is surrounded by a delicate connective tissue layer composed of fine, reticular fibers called the ___________.
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Endomysium
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Groups of skeletal muscle fibers, called ________, are bound together by a tougher connective tissue layer, called the ___________, which is composed of reticular fibers and thick collagen fibers.
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Fascicles
Perimysium |
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Groups of muscle fascicles are surrounded by ___________, a fibrous connective tissue layer composed largely of tough collagen fibers.
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Epimysium
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The fat deposits are often visible grossly in meat and are called the ________ of the meat
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Marbling
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When the impulse reaches the sarcoplasmic reticulum, it causes the release of stored ________ into the sarcoplasm.
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Calcium ions
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As the Ca++ diffuses into the myofibrils, it turns on the contraction process, which is powered by high-energy molecules of __________ ___________.
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Adenosine Triphosphate
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What is the difference between tetany and tetanus?
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Tetany is the contraction and tetanus is the disease.
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Muscles will continue to contract after the initial supply of ATP has been used, leaving _______.
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ADP
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The ADP is phosphorylated again from another source, ________ ____________.
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Creatinine phosphate
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The presence of ATP is required for __________ or __________ of the myosin from the actin, and also for the _________ of calcium ions to the sarcoplasmic reticulum.
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Relaxation or Detachment
Return |
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Muscle contraction is _____ to _____% efficient in regard to the accomplishment of work. The non-work portion is dissipated as ______.
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50-70%
Heat |
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When the fiber is stimulated to contract, small levers on the myosin filaments, called ________, ratchet back and forth and pull the __________ on both sides toward the center of the myosin filaments.
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Bridges
Actin filaments |
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The combined shortening of all the end-to-end sarcomere in a muscle fiber results in what we call a _______ ___________.
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Muscle Contraction
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An individual muscle fiber either contracts completely when it receives a nerve impulse or it does not contract at all. What is this know as?
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All or none principle
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How does the body produce movements that vary in range and strength when individual muscle fibers are doing all or nothing?
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By carefully controlling the number of muscle fibers it stimulates for a particular movement.
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A single muscle fiber contraction can be divided into 3 phases, ___________, _____________, and __________. How long does each last?
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Latent (0.01 seconds), Contraction (0.04 seconds), and Relaxation (0.05 seconds)
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Maximum contraction efficiency occurs if the nerve impulses arrive about ________ apart.
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0.1 Seconds
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Muscle shortening can occur in the absence of action potentials, referred to as _______ or ___________ ___________.
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Rigor or Physiologic Contracture
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The actin and myosin filaments remain in a continuous contracted state because sufficient ________ is not able to bring about _________.
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ATP
Relaxation |
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What is contracture that occurs after death called?
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Rigor Mortis
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Contraction strength varies and is achieved by ________ or by ___________.
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Multiple motor unit summation or Wave Summation
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One motor unit = weak contraction, Large number of motor units = strong contraction, what is this? All gradations of contraction strength are possible, depending on the # of ____ _____ stimulated.
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Motor Unit Summation
Motor Units |
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When a muscle is stimulated to contract before the muscle has relaxed, the strength of the subsequent contraction is increased, what is this called?
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Wave Summation
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When the frequency is sufficient such that the individual muscle twitches become fused into a single contraction, the strength is at a max, this condition is know as _______.
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Tetany
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Tetanus is a ____________ disease caused by a potent neurotoxin eloborated by the organism __________ _______. The neurotoxins reaches the ______ and prevents release of an inhibitory transmitter.
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Bacterial
Clostridium tetani CNS |
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Applying a stimuli of equal intensity a few seconds apart to muscle. Each successive muscle twitch has slightly more strength than the previous one, until optimal contraction strength is reached, is called what?
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Treppe or Staircase Phenomenon
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What is the difference between Wave Summation and Treppe?
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Wave Summation increases the number of muscles contracted, and stimulating it before it had time to relax.
Treppe allows the muscle fiber to relax but is then stimulated quickly. |
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What are the 6 ways of naming a muscle, give examples.
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Action - Flexor Muscles
Shape - Deltoid Muscles Location - Biceps Brachii Muscle |
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Direction of fibers - Rectus Abdominis Muscle
# of heads/division -Quadriceps femoris Muscle Attachment sites - Sternocephalic Muscle. |
x
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The immediate energy source that powers the sliding of the actin and myosin filaments is the compound _______, which is produced by the many ___________ in the muscle fibers.
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ATP
Mitochondria |
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When one of the phosphate groups is slit off ( forming ______), a considerable amount of _______ is released that powers the sliding of the _______ and ________ filaments.
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ADP
Energy Actin and Myosin |
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The "battery charger" that converts _____ back to _____is another compound in the muscle fiber and is called _______ _______. This is catalyzed by the enzyme ______ _______. What's the "formula" for this?
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ADP to ATP
Creatine phosphate (CP) Creatinine Kinase (CK) CP + ADP >> (CK) >> C + ATP |
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The ultimate source of energy use to produce ______ and ____ and keep the whole system operating comes from the _________ of nutrient molecules.
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ATP and CP
Catabolism |
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Two main compounds involved are _______ and ________. _________ is the sugar molecule that is the ________ energy source for most body cells, including the muscle cells.
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Glucose and Oxygen
Glucose Primary |
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Glucose + Oxygen ---> _______.
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Creatine Phosphate (CP)
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Glucose is stored in the fibers in the form of ___________, and oxygen is stored attached to large protein molecules called __________.
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Glycogen
Myoglobin |
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As long as the oxygen supply is adequate to keep up with the energy needs of the fiber, the process is known as ________ ________, and the ________ amount of energy is extracted from each glucose molecule.
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Aerobic Metabolism
Maximum |
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Sometimes, during periods of strenuous activity, the need for oxygen _______ the available supply and muscle fibers must shift to what is called ________ ________ to produce the energy required for continued activity.
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Exceeds
Anaerobic Metabolism |
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_________ metabolism is not as efficient as ________ metabolism and results in ______ ______ formation as a byproduct of incomplete glucose breakdown.
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Anaerobic
Aerobic Lactic acid |
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The _____ _____ can accumulate in the muscle tissue and cause discomfort.
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Lactic Acid
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Afterward the lactic acid diffuses into the bloodstream and goes to the______, where it is converted back to _______ by a process that requires oxygen.
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Liver
Glucose |
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Glucose is stored as ___________.
Oxygen attaches to large protein molecules called _________. |
Glycogen
Myoglobin |
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________ __________ means that as long as the oxygen supply is adequate to keep up with the energy needs of the muscle fiber.
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Aerobic Metabolism
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Muscles are less than 100% efficient at converting ________ to useful work. A considerable amount of the energy produced in muscles is lost in the form of ______.
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Energy
Heat |
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_________ activity is one of the major heat-generating mechanisms that the body uses to maintain a constant internal temperature.
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Muscular
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If heat production exceeds body needs, excess must be eliminated by mechanisms such as _________ or _________.
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Panting or Sweating
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Under cold conditions, the body may need to increase the production of heat to avoid _________. It often does this by producing the small, spasmodic muscle contractions we know as _________.
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Hypothermia
Shivering |
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Cardiac muscle cells form __________ networks around the cardiac chambers. The ________ and ________ ___________ of cardiac muscle allow it to start contracting early in the _________ period before birth.
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Elaborate
Arrangement and Physical Characteristics Embryonic |
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Cardiac muscle cells are much __________ than skeletal muscle cells and have only one _______ per cell.
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Smaller
Nucleus |
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The firm end-to-end attachments between cardiac muscle cells, under the microscope appear as ______, _________ lines between the cells.
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Dark
Transverse |
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These attachment sites are called ________ ______, which securely fasten the cells together.
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Intercalated Disks
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With cardiac muscle, each muscle cell contracts rhythmically with no ________ _________ at all. Each cell contracts at a constant rate set by its own internal clock.
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External Stimulation
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However, if two cells touch, the _______ contracting cells adopts the ______ cell‘s contraction rate.
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Slower
Faster |
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The ________ _________ system consists entirely of cardiac muscle cells. The impulse that starts each heart beat begins in the heart‘s "pacemaker", or the ________ ________ located in the wall of the right atrium.
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Impulse Conduction
Sinoatrial (SA) Node |
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The nerves to the heart are from both divisions of the autonomic portion of the nervous system, that is, the ___________ and ______________ system.
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Sympathetic and Parasympathetic
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The ________ fibers stimulate the heart to beat _______ and ______ as part of the _______ or ______ response that kicks in when an animal feels threatened.
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Sympathetic
Harder and Faster Fight or Flight |
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The __________ fibers do the opposite in that they inhibit cardiac function, there by causing the heart to beat more ______ and with less force when the body is relaxed and resting.
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Parasympathetic
Slowly |
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Sympathetic =
Parasympathetic = |
Fight or Flight
Digestion |
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Smooth Muscle is found in two main forms:
1. 2. |
1. Large sheets of cells in the walls of some hollow organs (visceral smooth muscle) and,
2. Small, discrete groups of cells (multiunit smooth muscle). |
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Smooth muscle cells are small and ______ shaped with a single _______ in the center.
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Spindle
Nucleus |
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They have a ________, ________ appearance under the microscope because their filaments of actin and myosin are not arranged in _______ _________ as in skeletal and cardiac muscle.
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Smooth and Homogeneous
Parallel Myofibrils |
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Small contractile units of actin and myosin filaments ________ the cell at various angles and are attached at both ends to "______ ______" that correspond to the ___ lines of skeletal muscle.
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Crisscross
Dense Bodies Z |
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Because their contractile units are not organized into regular, parallel sarcomeres, individual smooth muscle cells can ________ to a greater extent than skeletal or cardiac muscle cells.
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Shorten
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Visceral smooth muscle is found in the walls of many soft, _____ ______, which are also known by the general name _____. Its cells are linked to form large sheets in the walls of organs such as ____, _____, _____ and ____.
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Internal Organs
Viscera Stomach, Intestines, Uterus, and Urinary Bladder |
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Like cardiac muscle, visceral smooth muscle contracts without the need for _______ ________. It does react to _______, however, by contracting more strongly.
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External Stimulation
Stretching |
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This is useful in the _______ _______, where the presence of food in the lumen stretches the tube and the smooth muscle in its wall.
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Gastrointestinal Tract
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Like cardiac muscle, the nerve supply to smooth muscle consists of the ______ and _______ divisions of the autonomic nervous system.
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Sympathetic and Parasympathetic
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Sympathetic stimulation _______ visceral smooth muscle activity, and the parasympathetic stimulation _________ it.
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Decreases
Increases |
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Multiunit smooth muscle is _______ and _______. Multiunit smooth muscle is made up of individual smooth muscle cells or small groups of cells.
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Small and Delicate
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Contractions of multiunit smooth muscle are not _________. They require impulses from ___________ nerves to contract.
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Automatic
Autonomic |
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The actions of multiunit smooth muscle are ________ and _________ _________. This allow fine control of actions, such as adjusting the size of ___________.
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Specific and Carefully Controlled
The pupil of the eye |
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It also allows delicate control of ____________ throughout the body and airflow through the lungs by adjusting the size of _____ ________ and ___ _________ according to the body‘s needs.
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Blood flow
Blood vessels Air passageways |