Chapter 2 – Key Terms
amphiarthrosis slightly mobile joint
articular capsule connective tissue structure that encloses the joint cavity of a synovial joint
articular cartilage thin layer of hyaline cartilage that covers the articulating surfaces of bones at a synovial joint
articular disc meniscus; a fibrocartilage structure found between the bones of some synovial joints; provides padding or smooths movements between the bones; strongly unites the bones together
articulation joint of the body
ball-and-socket joint synovial joint formed between the spherical end of one bone (the ball) that fits into the depression of a second bone (the socket); found at the hip and shoulder joints; functionally classified as a multiaxial joint
biaxial joint type of diarthrosis; a joint that allows for movements within two planes (two axes)
bone hard, dense connective tissue that forms the structural elements of the skeleton
bursa connective tissue sac containing lubricating fluid that prevents friction between adjacent structures, such as skin and bone, tendons and bone, or between muscles
cartilaginous joint joint at which the bones are united by hyaline cartilage (synchondrosis) or fibrocartilage (symphysis)
central canal longitudinal channel in the center of each osteon; contains blood vessels, nerves, and lymphatic vessels; also known as the Haversian canal
compact bone dense osseous tissue that can withstand compressive forces
condyloid joint synovial joint in which the shallow depression at the end of one bone receives a rounded end from a second bone or a rounded structure formed by two bones; found at the metacarpophalangeal joints of the fingers or the radiocarpal joint of the wrist; functionally classified as a biaxial joint
diaphysis tubular shaft that runs between the proximal and distal ends of a long bone
diarthrosis freely mobile joint
endochondral ossification process in which bone forms by replacing hyaline cartilage
endosteum delicate membranous lining of a bone’s medullary cavity
epiphyseal line completely ossified remnant of the epiphyseal plate
epiphyseal plate (also, growth plate) sheet of hyaline cartilage in the metaphysis of an immature bone; replaced by bone tissue as the organ grows in length
epiphysis wide section at each end of a long bone; filled with spongy bone and red marrow
extrinsic ligament ligament located outside of the articular capsule of a synovial joint
fibrous joint joint where the articulating areas of the adjacent bones are connected by fibrous connective tissue
flat bone thin and curved bone; serves as a point of attachment for muscles and protects internal organs
gomphosis type of fibrous joint in which the root of a tooth is anchored into its bony jaw socket by strong periodontal ligaments
hematopoiesis production of blood cells, which occurs in the red marrow of the bones
hinge joint synovial joint at which the convex surface of one bone articulates with the concave surface of a second bone; includes the elbow, knee, ankle, and interphalangeal joints; functionally classified as a uniaxial joint
interosseous membrane wide sheet of fibrous connective tissue that fills the gap between two parallel bones, forming a syndesmosis; found between the radius and ulna of the forearm and between the tibia and fibula of the leg
intramembranous ossification process by which bone forms directly from mesenchymal tissue
intrinsic ligament ligament that is fused to or incorporated into the wall of the articular capsule of a synovial joint
irregular bone bone of complex shape; protects internal organs from compressive forces
joint site at which two or more bones or bone and cartilage come together (articulate)
joint cavity space enclosed by the articular capsule of a synovial joint that is filled with synovial fluid and contains the articulating surfaces of the adjacent bones
ligament strong band of dense connective tissue spanning between bones
long bone cylinder-shaped bone that is longer than it is wide; functions as a lever
medullary cavity hollow region of the diaphysis; filled with yellow marrow
meniscus articular disc
modeling process, during bone growth, by which bone is resorbed on one surface of a bone and deposited on another
multiaxial joint type of diarthrosis; a joint that allows for movements within three planes (three axes)
osseous tissue bone tissue; a hard, dense connective tissue that forms the structural elements of the skeleton
ossification center cluster of osteoblasts found in the early stages of intramembranous ossification
osteoblast cell responsible for forming new bone
osteoclast cell responsible for resorbing bone
osteocyte primary cell in mature bone; responsible for maintaining the matrix
osteogenic cell undifferentiated cell with high mitotic activity; the only bone cells that divide; they differentiate and develop into osteoblasts
osteoid uncalcified bone matrix secreted by osteoblasts
osteon (also, Haversian system) basic structural unit of compact bone; made of concentric layers of calcified matrix
perichondrium membrane that covers cartilage
periosteum fibrous membrane covering the outer surface of bone and continuous with ligaments
pivot joint synovial joint at which the rounded portion of a bone rotates within a ring formed by a ligament and an articulating bone; functionally classified as uniaxial joint
plane joint synovial joint formed between the flattened articulating surfaces of adjacent bones; functionally classified as a multiaxial joint
primary ossification center region, deep in the periosteal collar, where bone development starts during endochondral ossification
proximal radioulnar joint articulation between head of radius and radial notch of ulna; uniaxial pivot joint that allows for rotation of radius during pronation/supination of forearm
remodeling process by which osteoclasts resorb old or damaged bone at the same time as and on the same surface where osteoblasts form new bone to replace that which is resorbed
red marrow connective tissue in the interior cavity of a bone where hematopoiesis takes place
saddle joint synovial joint in which the articulating ends of both bones are convex and concave in shape, such as at the first carpometacarpal joint at the base of the thumb; functionally classified as a biaxial joint
secondary ossification center region of bone development in the epiphyses
sesamoid bone small, round bone embedded in a tendon; protects the tendon from compressive forces
short bone cube-shaped bone that is approximately equal in length, width, and thickness; provides limited motion
spongy bone (also, cancellous bone) trabeculated osseous tissue that supports shifts in weight distribution
suture fibrous joint that connects the bones of the skull (except the mandible); an immobile joint (synarthrosis)
symphysis type of cartilaginous joint where the bones are joined by fibrocartilage
synarthrosis immobile or nearly immobile joint
synchondrosis type of cartilaginous joint where the bones are joined by hyaline cartilage
syndesmosis type of fibrous joint in which two separated, parallel bones are connected by an interosseous membrane
synovial fluid thick, lubricating fluid that fills the interior of a synovial joint
synovial joint joint at which the articulating surfaces of the bones are located within a joint cavity formed by an articular capsule
synovial membrane thin layer that lines the inner surface of the joint cavity at a synovial joint; produces the synovial fluid
tendon dense connective tissue structure that anchors a muscle to bone
tendon sheath connective tissue that surrounds a tendon at places where the tendon crosses a joint; contains a lubricating fluid to prevent friction and allow smooth movements of the tendon
trabeculae (singular = trabecula) spikes or sections of the lattice-like matrix in spongy bone
uniaxial joint type of diarthrosis; joint that allows for motion within only one plane (one axis)
yellow marrow connective tissue in the interior cavity of a bone where fat is stored