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15 Cards in this Set
- Front
- Back
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There are three main types of muscle: ________ muscle is involved in support and movement, propulsion of blood in the venous system and thermoregulation. It appears striated, is under voluntary (somatic) control, is polynucleated and can be divided into _______ fibers that carry out oxidative phosphorylation and _______ fibers that rely on anaerobic metabolism. ________ muscle is in the respiratory, reproductive, cardiovascular and digestive systems. It appears nonstriated, is under involuntary (autonomic) control and is uninucleated. It can display _______, or contraction without neural input. ________ muscle comprises the contractile tissue of the heart. It appears striated, is under involuntary (autonomic) control, and is uninucleated (sometimes binucleated). It can also display myogenic activity. Cells are connected with ________ that contain ________. |
skeletal red (slow-twitch) white (fast-twitch) smooth myogenic activity cardiac intercalated disks gap junctions |
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The ________ is the basic contractile unit of striated muscle. They are made of thick _______ and thin ______ filaments. ________ are found on the thin filament and regulate actin-myosin interactions. |
sarcomere myosin actin troponin and tropomyosin |
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The sarcomere can be divided into different lines, zones and bands. The boundaries of each sarcomere are defined by _______. The _______ is located in the center of the sarcomere. The _______ contain only tin filaments. The _______ consists of only thick filaments. The _______ contains the thick filaments in their entirety. It is the only part of the sarcomere that maintains a constant size during contraction. |
Z-lines M-line I-band H-zone A-band |
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Sarcomeres attach end-to-end to become _______, and each _______ contain many myofibrils. Myofibrils are surrounded by the ________, a calcium-containing modified endoplasmic reticulum, and the cell membrane of myocytes is known as the _______. A system of _______ is connected to the sarcolemma and oriented perpendicularly to the myofibrils, allowing the incoming signal to reach all parts of the muscle. |
myofibrils myocyte (muscle cell or muscle fiber) sarcoplasmic reticulum sarcolemma T-tubules |
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Muscle contraction begins at the _______, where the motor neuron releases _______ that binds to the receptors on the sarcolemma, causing depolarization. This depolarization spreads down the sarcolemma to the _______, triggering the release of _______. Calcium binds to ________, causing a shift in _______ and exposure of the ________ on the _______. Shortening of the sarcomere occurs as _______ heads bind to the exposed sites on ______, forming cross bridges and pulling the _______ along the _______, resulting in contraction. This is known as the ________. The muscle relaxes when ________ is degraded by ________, terminating the signal and allowing calcium to be brought back into the ________. _______ binds to the myosin head, allowing it to release from actin. |
neuromuscular junction acetylcholine T-tubules calcium ions troponin tropomyosin myosin-binding sites actin thin filament myosin actin actin filament thick filament sliding filament model acetylcholine acetylcholinesterase sarcoplasmic reticulum ATP |
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Muscle cells exhibit an all-or-nothing response called a ________. Addition of multiple simple twitches before the muscle has an opportunity to fully relax is called _______. Simple twitches that occur so frequently as to not let the muscle relax at all can lead to _______, a more prolonged and stronger contraction. |
simple twitch frequency summation tetanus |
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Muscle cells have additional energy reserves to reduce _______ (the difference between the amount of oxygen needed and the amount present) and forestall fatigue. _______ can transfer a phosphate group to ADP, forming ATP. _______ is a heme-containing protein that is a muscular oxygen reserve. |
oxygen debt creatine phosphate myoglobin |
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Internal skeletons (like those in humans) are called _______; external skeletons (like those in arthropods) are called ________. |
endoskeletons exoskeletons |
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The human skeletal system can be divided into: The ________ consists of structures in the midline such as the skull, vertebral column, ribcage and hyoid bone. The ________ consists of the bones of the limbs, the pectoral girdle and the pelvis. |
axial skeleton appendicular skeleton |
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Bone is derived from _______ and includes both _______ types. _______ provides strength and is dense. _______ has a lattice-like structure consisting of bony spicules known as _______. The cavities are filled with _______. Long bones contain shafts called _______ that flare to form ______ and that terminate in _______. The epiphysis contains an _______ that causes linear growth of the bone. Bone is surrounded by a layer of connective tissue called _______. Bones are attached to muscles by _______ and to each other by _______. |
embryonic mesoderm compact and spongy (cancellous) compact bone spongy (cancellous) bone trabeculae bone marrow diaphyses metaphyses epiphyses epiphyseal (growth) plate periosteum tendons ligaments |
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_______ has both organic components, like collagen, glycoproteins and other peptides, and inorganic components, like ______. Bone is organized into concentric rings called ________ around a central ______. This structural unit is called _______. Between lamellar rings are _______, where _______ reside, which are connect with _______ to allow for nutrient and waste transfer. |
bone matrix hydroxyapatite lamellae Haversian or Volkmann's canal osteon or Haversian system lacunae osteocytes canaliculi |
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Bone remodeling is carried out by _______. _______ build bone, while _______ resorb bone. _______ increases resorption of bone, increasing _______ concentrations in the blood. _______ also increases resorption of bone, leading to increased turnover and, subsequently, the production of stronger bone. _______ increases bone formation, decreasing calcium concentrations in the blood. |
osteoblasts and osteoclasts osteoblasts osteoclasts parathyroid hormone calcium and phosphate vitamin D calcitonin |
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Cartilage is a firm, elastic material secreted by _______. Its matrix is called _______. Cartilage is usually found in areas that require more flexibility or cushioning. Cartilage is avascular and is not innervated. |
chondrocytes chondrin |
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In fetal life, bone forms from cartilage through _______. Some bones, especially those of the skull, form directly from _______ in _______. |
endochondral ossification undifferentiated tissue (mesenchyme) intramembranous ossification |
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Joints may be classified as: _______ joints are fused together to form sutures or similar fibrous joints. _______ joints are usually strengthened by ligaments and contain a _______. _______, secreted by the _______, aids in motion by lubricating the joint. Each bone in the joint is coated with _______ to aid in movement and provide cushioning. |
immovable movable synovial capsule synovial fluid synovium articular cartilage |
