| Term 
 | Definition 
 
        | Muscle that is connected to at least two bones |  | 
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        | Term 
 | Definition 
 
        | Cords of elastic connective tissue that connect muscle to bone |  | 
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        | Term 
 
        | What are the four main functions of muscles? |  | Definition 
 
        | 1. Produce movement 2. Maintain posture
 3. Stabilize joints
 4. Generate heat
 |  | 
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        | Term 
 | Definition 
 
        | Numerous bundles of individual muscle cells. |  | 
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        | Term 
 | Definition 
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        | Term 
 | Definition 
 
        | The plasma membrane of a muscle fiber |  | 
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        | Term 
 | Definition 
 
        | Rod-like structures found in the sarcoplasm of a muscle fiber which contain the fiber's contractile machinery. |  | 
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        | Term 
 
        | What proteins make up the filaments in a myofibril? |  | Definition 
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        | Term 
 | Definition 
 
        | A saclike membranous network that surrounds each myofibril. Stores calcium. |  | 
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        | Term 
 
        | Transverse Tubules (T-Tubules) |  | Definition 
 
        | Structures that transmit action potentials from the sarcolemma into the cell's interior, triggering the release of calcium from the sarcoplasmic reticulum. |  | 
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        | Term 
 
        | Lateral Sacs (Terminal Cisternae) |  | Definition 
 
        | Located near the t-tubules and store caclium |  | 
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        | Term 
 | Definition 
 
        | A t-tubule and the two lateral sacs it is associated with. |  | 
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        | Term 
 | Definition 
 
        | Protein fibers in the myofibril |  | 
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        | Term 
 | Definition 
 
        | Fundamental repeating unit that creates a myofibril |  | 
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        | Term 
 | Definition 
 
        | Border the sarcomere on either side and run perpendicular to the long axis. They also anchor the thin filaments at one end |  | 
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        | Term 
 | Definition 
 
        | Run perpendicular to the long axis and connect the thick filaments. |  | 
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        | Term 
 | Definition 
 
        | Thick filaments of the sarcomere |  | 
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        | Term 
 | Definition 
 
        | A light region in the center of the A bands in which only thick filaments are present. |  | 
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        | Term 
 | Definition 
 
        | Light region in which only the thin filaments are present. |  | 
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        | Term 
 | Definition 
 
        | Compose the thick and thin filaments of the sarcomere. Referred to as contractile proteins. |  | 
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        | Term 
 | Definition 
 
        | Actin monomers that are the basic components of each thin filament. Contains a myosin binding site. |  | 
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        | Term 
 | Definition 
 
        | Polymer made up of G actins that are bound together. Makes up actin strands found in thin filaments. |  | 
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        | Term 
 | Definition 
 
        | Protein that enable muscle fibers to start or stop contracting. |  | 
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        | Term 
 
        | What are the two regulatory proteins present in thin filaments of the sarcomere? |  | Definition 
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        | Term 
 | Definition 
 
        | Long fibrous molecule that extends and blocks the myosin binding sites in muscles at rest. |  | 
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        | Term 
 | Definition 
 
        | Complex of three proteins that are responsible for the actions produced by calcium ions which bind to it and trigger muscle contraction. |  | 
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        | Term 
 
        | Thick filaments are composed of what type of molecule? |  | Definition 
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        | Term 
 | Definition 
 
        | The heads of myosin molecules that bridge the gap between thick and thin filaments |  | 
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        | Term 
 | Definition 
 
        | The middle of the thick filament in which no crossbridges are present. |  | 
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        | Term 
 
        | What two sites do myosin heads possess? |  | Definition 
 
        | Actin-binding site that can bind to actin molecules and ATPase site that controls enzymatic activity and hydrolyzes ATP. |  | 
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        | Term 
 
        | During muscle contractions what happens to each region of the sarcomere? |  | Definition 
 
        | The A band doesn't change. I band and H zone shorten. Z lines move closer to each other. |  | 
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        | Term 
 | Definition 
 
        | Muscles contract because the thick and thin filaments of the myofibril slide past one another. |  | 
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        | Term 
 | Definition 
 
        | The mechanism that drives the sliding of thick and thin filaments past one another during muscle contraction. |  | 
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        | Term 
 
        | Excitation-Contraction Coupling |  | Definition 
 
        | The sequence of events that links the action potential to the contraction |  | 
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        | Term 
 | Definition 
 
        | Receive end-plate potentials, resulting in depolarization |  | 
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        | Term 
 | Definition 
 
        | A compound that donates its phosphate to ADP to form ATP which muscles rely on for immediate use during contraction. (Use while preparing to use the energy produced by oxidative phosphorylation) |  | 
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        | Term 
 
        | Creatine phosphate + ADP in the presence of creatine kinase yields... |  | Definition 
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        | Term 
 
        | Creatine is broken down into... |  | Definition 
 
        | Creatinine which is excreted from the body in the urine |  | 
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        | Term 
 
        | Creatinine can be measured in what bodily fluids? |  | Definition 
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        | Term 
 
        | Creatinine measurements are performed in order to evaluate what? |  | Definition 
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        | Term 
 | Definition 
 
        | 0.7-1.3 mg/dL for men and 06.-1.1 mg/dL for women |  | 
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        | Term 
 
        | Increased levels of creatinine can result from what? |  | Definition 
 
        | Dehydration, renal failure, tubular necrosis, glomerulonephritis, diabetic nephropathy and rhabdomyolysis |  | 
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        | Term 
 
        | Decreased levels of Creatinine can result from what? |  | Definition 
 
        | Muscular dystrophy and myasthenia gravis |  | 
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        | Term 
 | Definition 
 
        | Normal values 10-120 micrograms per liter. An increase in serum indicates injury or stress to muscle tissue, the hear or the brain. |  | 
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        | Term 
 | Definition 
 
        | Lacks striations Is under involuntary control by the autonomic nervous system
 Contains actin and myosin
 Does not contain sarcomeres
 |  | 
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        | Term 
 
        | Are actin and myosin larger in skeletal muscle or smooth muscle? |  | Definition 
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