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7.6.6: Key Terms

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    when a bone moves away from the midline of the body
    (AChE) enzyme that breaks down ACh into acetyl and choline
    globular contractile protein that interacts with myosin for muscle contraction
    movement of the limbs inward after abduction
    joint that allows slight movement; includes syndesmoses and symphyses
    angular movement
    produced when the angle between the bones of a joint changes
    appendicular skeleton
    composed of the bones of the upper limbs, which function to grasp and manipulate objects, and the lower limbs, which permit locomotion
    appositional growth
    increase in the diameter of bones by the addition of bone tissue at the surface of bones
    any place where two bones are joined
    auditory ossicle
    (also, middle ear) transduces sounds from the air into vibrations in the fluid-filled cochlea
    axial skeleton
    forms the central axis of the body and includes the bones of the skull, the ossicles of the middle ear, the hyoid bone of the throat, the vertebral column, and the thoracic cage (ribcage)
    ball-and-socket joint
    joint with a rounded, ball-like end of one bone fitting into a cuplike socket of another bone
    (also, osseous tissue) connective tissue that constitutes the endoskeleton
    bone remodeling
    replacement of old bone tissue by new bone tissue
    process of deposition of mineral salts in the collagen fiber matrix that crystallizes and hardens the tissue
    cardiac muscle tissue
    muscle tissue found only in the heart; cardiac contractions pump blood throughout the body and maintain blood pressure
    eight bones that comprise the wrist
    cartilaginous joint
    joint in which the bones are connected by cartilage
    movement of a limb in a circular motion
    S-shaped bone that positions the arms laterally
    compact bone
    forms the hard external layer of all bones
    condyloid joint
    oval-shaped end of one bone fitting into a similarly oval-shaped hollow of another bone
    coxal bone
    hip bone
    cranial bone
    one of eight bones that form the cranial cavity that encloses the brain and serves as an attachment site for the muscles of the head and neck
    movement downward of a bone, such as after the shoulders are shrugged and the scapulae return to their normal position from an elevated position; opposite of elevation
    central shaft of bone, contains bone marrow in a marrow cavity
    joint that allows for free movement of the joint; found in synovial joints
    bending at the ankle such that the toes are lifted toward the knee
    movement of a bone upward, such as when the shoulders are shrugged, lifting the scapulae
    endochondral ossification
    process of bone development from hyaline cartilage
    skeleton of living cells that produces a hard, mineralized tissue located within the soft tissue of organisms
    epiphyseal plate
    region between the diaphysis and epiphysis that is responsible for the lengthwise growth of long bones
    rounded end of bone, covered with articular cartilage and filled with red bone marrow, which produces blood cells
    movement of the sole of the foot outward, away from the midline of the body; opposite of inversion
    a secreted cellular product external skeleton that consists of a hard encasement on the surface of an organism
    movement in which the angle between the bones of a joint increases; opposite of flexion
    facial bone
    one of the 14 bones that form the face; provides cavities for the sense organs (eyes, mouth, and nose) and attachment points for facial muscles
    (also, thighbone) longest, heaviest, and strongest bone in the body
    fibrous joint
    joint held together by fibrous connective tissue
    (also, calf bone) parallels and articulates with the tibia
    flat bone
    thin and relatively broad bone found where extensive protection of organs is required or where broad surfaces of muscle attachment are required
    movement in which the angle between the bones decreases; opposite of extension
    extends from the elbow to the wrist and consists of two bones: the ulna and the radius
    gliding movement
    when relatively flat bone surfaces move past each other
    the joint in which the tooth fits into the socket like a peg
    Haversian canal
    contains the bone’s blood vessels and nerve fibers
    hinge joint
    slightly rounded end of one bone fits into the slightly hollow end of the other bone
    only bone of the arm
    hydrostatic skeleton
    skeleton that consists of aqueous fluid held under pressure in a closed body compartment
    hyoid bone
    lies below the mandible in the front of the neck
    extension past the regular anatomical position
    intervertebral disc
    composed of fibrous cartilage; lies between adjacent vertebrae from the second cervical vertebra to the sacrum
    intramembranous ossification
    process of bone development from fibrous membranes
    soles of the feet moving inward, toward the midline of the body
    irregular bone
    bone with complex shapes; examples include vertebrae and hip bones
    point at which two or more bones meet
    layer of compact tissue that surrounds a central canal called the Haversian canal
    lateral rotation
    rotation away from the midline of the body
    long bone
    bone that is longer than wide, and has a shaft and two ends
    lower limb
    consists of the thigh, the leg, and the foot
    medial rotation
    rotation toward the midline of the body
    five bones that comprise the palm
    one of the five bones of the foot
    motor end plate
    sarcolemma of the muscle fiber that interacts with the neuron
    long cylindrical structures that lie parallel to the muscle fiber
    small structures that make up myofibrils
    contractile protein that interacts with actin for muscle contraction
    movement of the thumb toward the fingers of the same hand, making it possible to grasp and hold objects
    osseous tissue
    connective tissue that constitutes the endoskeleton
    (also, osteogenesis) process of bone formation by osteoblasts
    bone cell responsible for bone formation
    large bone cells with up to 50 nuclei, responsible for bone remodeling
    mature bone cells and the main cell in bone tissue
    cylindrical structure aligned parallel to the long axis of the bone
    (also, kneecap) triangular bone that lies anterior to the knee joint
    pectoral girdle
    bones that transmit the force generated by the upper limbs to the axial skeleton
    pelvic girdle
    bones that transmit the force generated by the lower limbs to the axial skeleton
    one of the bones of the fingers or toes
    pivot joint
    joint with the rounded end of one bone fitting into a ring formed by the other bone
    planar joint
    joint with bones whose articulating surfaces are flat
    plantar flexion
    bending at the ankle such that the heel is lifted, such as when standing on the toes
    movement in which the palm faces backward
    anterior movement of a bone in the horizontal plane
    bone located along the lateral (thumb) side of the forearm; articulates with the humerus at the elbow
    process by which osteoclasts release minerals stored in bones
    movement in which a joint moves back into position after protraction
    one of 12 pairs of long, curved bones that attach to the thoracic vertebrae and curve toward the front of the body to form the ribcage
    rotational movement
    movement of a bone as it rotates around its own longitudinal axis
    saddle joint
    joint with concave and convex portions that fit together; named because the ends of each bone resemble a saddle
    plasma membrane of a skeletal muscle fiber
    functional unit of skeletal muscle
    flat, triangular bone located at the posterior pectoral girdle
    sesamoid bone
    small, flat bone shaped like a sesame seed; develops inside tendons
    short bone
    bone that has the same width and length, giving it a cube-like shape
    skeletal muscle tissue
    forms skeletal muscles, which attach to bones and control locomotion and any movement that can be consciously controlled
    bone that supports the structures of the face and protects the brain
    smooth muscle tissue
    occurs in the walls of hollow organs such as the intestines, stomach, and urinary bladder, and around passages such as the respiratory tract and blood vessels
    spongy bone tissue
    forms the inner layer of all bones
    (also, breastbone) long, flat bone located at the front of the chest
    movement of the radius and ulna bones of the forearm so that the palm faces forward
    sutural bone
    small, flat, irregularly shaped bone that forms between the flat bones of the cranium
    short fiber of connective tissue that holds the skull bones tightly in place; found only in the skull
    hyaline cartilage covers the end of the bone, but the connection between bones occurs through fibrocartilage; symphyses are found at the joints between vertebrae
    joint that is immovable
    bones joined by hyaline cartilage; synchondroses are found in the epiphyseal plates of growing bones in children
    joint in which the bones are connected by a band of connective tissue, allowing for more movement than in a suture
    synovial joint
    only joint that has a space between the adjoining bones
    one of the seven bones of the ankle
    thick filament
    a group of myosin molecules
    thin filament
    two polymers of actin wound together along with tropomyosin and troponin
    thoracic cage
    (also, ribcage) skeleton of the chest, which consists of the ribs, thoracic vertebrae, sternum, and costal cartilages
    (also, shinbone) large bone of the leg that is located directly below the knee
    lamellae that are arranged as rods or plates
    acts to block myosin binding sites on actin molecules, preventing cross-bridge formation and preventing contraction until a muscle receives a neuron signal
    binds to tropomyosin and helps to position it on the actin molecule, and also binds calcium ions
    bone located on the medial aspect (pinky-finger side) of the forearm
    vertebral column
    (also, spine) surrounds and protects the spinal cord, supports the head, and acts as an attachment point for ribs and muscles of the back and neck

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