Openstax Anatomy & Physiology Chapter 6

Tuberosity

large rounded projection

Trochanter

large, rough projection

secondary ossification center

region of bone development in the epiphyses

osteon

(also, Haversian system) basic structural unit of compact bone; made of concentric layers of calcified matrix

perforating canal

(also, Volkmann's canal) channel that branches off from the central canal and houses vessels and nerves that extend to the periosteum and endosteum

spongy bone

(also, cancellous bone) trabeculated osseous tissue that supports shifts in weight distribution

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

canaliculi

(singular = canaliculus) channels within the bone matrix that house one of an osteocyte's many cytoplasmic extensions that it uses to communicate and receive nutrients, moves nutrients across lamellae

lacunae

(singular = lacuna) spaces in a bone that house an osteocyte

trabeculae

(singular = trabecula) spikes or sections of the lattice-like matrix in spongy bone

Neck

A narrow connection between the epiphysis and the diaphysis

Epicondyle

A projection situated above a condyle

Calcium blood levels are controlled by

Calcitonin and parathyroid hormone, Calcitonin stops osteoclasts making bones take up more calcium, parathyroid hormone stimulates osteoclasts, releasing calcium from breaking down bone

Chondrocytes

Cells that secrete cartilage.

Line

Narrow ridge of bone; less prominent than a crest

Crest

Narrow ridge of bone; usually prominent

remodeling

The process of resorption and formation of bone

epiphyseal line

When osteoblasts and osteoclasts stop expanding and reforming the bone from the plate. All chondrocytes get calcified and replaced with bone tissue

primary ossification center

a region where bone tissue will replace most of the cartilage

Trochlea

a smooth, grooved articular process shaped like a pulley

Fissure

an opening; a groove; a split

Process

any bony prominence

Projection

area of bone raised from the rest of the bone

greenstick fracture

bending and incomplete break of a bone; most often seen in children

fracture hematoma

blood clot that forms at the site of a broken bone

comminuted fracture

bone breaks into many fragments

projection

bone markings where part of the surface sticks out above the rest of the surface, where tendons and ligaments attach

irregular bone

bone of complex shape; protects internal organs from compressive forces

osseous tissue

bone tissue; a hard, dense connective tissue that forms the structural elements of the skeleton

Head

bony expansion carried on a narrow neck

fracture

broken bone

hydroxapatite crystals

calcium based formation, very strong chemical compound that makes up bone

The role of calcium, vitamin D, vitamin K, fluoride, and omega-3 fatty acids

calcium is needed for hydroxyapatite crystals, vitamin D is vital in absorbing calcium, vitamin K has similar role to vitamin D, fluoride rearranges hydroxyapatite crystals, omega-3 fatty acids reduces inflammation helping osteoblasts become more active

Sinus

cavity within a bone

osteoblast

cell responsible for forming new bone

osteoclast

cell responsible for resorbing bone, multinuclear, sits on surface and breaks down bone and secretes calcium, differentiates from white blood cells rather than osteogenic cells

external callus

collar of hyaline cartilage and bone that forms around the outside of a fracture, blood vessels repair

hypercalcemia

condition characterized by abnormally high levels of calcium

hypocalcemia

condition characterized by abnormally low levels of calcium

yellow marrow

connective tissue in the interior cavity of a bone where fat is stored

red marrow

connective tissue in the interior cavity of a bone where hematopoiesis takes place

short bone

cube-shaped bone that is approximately equal in length, width, and thickness; provides limited motion

long bone

cylinder-shaped bone that is longer than it is wide; functions as a lever

endosteum

delicate membranous lining of a bone's medullary cavity, made up osteoblasts, houses bone growth, repair, remodeling

compact bone

dense osseous tissue that can withstand compressive forces

osteoporosis

disease characterized by a decrease in bone mass; occurs when the rate of bone resorption exceeds the rate of bone formation, a common occurrence as the body ages

orthopedist

doctor who specializes in diagnosing and treating musculoskeletal disorders and injuries

Bone matrix

everything inside the osteon

Bigger bones are caused by

extra pressure on bones, causing bones to become denser and bigger, athletes have bigger and denser bones

internal callus

fibrocartilaginous matrix, in the endosteal region, between the two ends of a broken bone, hardened osteoid matrix and bone repairs

periosteum

fibrous membrane covering the outer surface of bone and continuous with ligaments, covers all of the bone's outer surface area but where the articular cartilage, made of outer cellular layer and one fibrous layer

oblique fracture

fracture at an angle to the bone

impacted fracture

fracture in which one bone fragment is pushed into another

Groove

furrow

bone

hard, dense connective tissue that forms the structural elements of the skeleton, called osseous tissue

Foramen

hole in a bone

medullary cavity

hollow region of the diaphysis; filled with yellow marrow

transverse fracture

horizontal fracture

modeling

horizontal growth of bones

diploë

layer of spongy bone, that is sandwiched between two the layers of compact bone found in flat bones

central canal

longitudinal channel in the center of each osteon; contains blood vessels, nerves, and lymphatic vessels; also known as the Haversian canal

closed reduction

manual manipulation of a broken bone to set it into its natural position without surgery

zone of maturation

matured chondrocytes closer to epiphysis than proliferate zone

calcified matrix zone

most chondrocytes dead; matrix being replaced by bone, closer to epiphysis than zone of maturation

hole

opening or depression in a bone

skeletal system

organ system composed of bones and cartilage that provides for movement, support, and protection

meatus/canal

passageway through a bone

Spine

pointed process

osteocyte

primary cell in mature bone; responsible for maintaining the mineral concentration via enzymes

intramembranous ossification

process by which bone forms directly from mesenchymal tissue

endochondral ossification

process in which bone forms by replacing hyaline cartilage

Calcitrol

produced by kidneys, active form of vitamin D, helps absorb calcium and phosphate in digestive system to release through urine, decreases calcium blood level

proliferate zone

produces new chondrocytes

hematopoiesis

production of blood cells, which occurs in the red marrow of the bones

spiral fracture

ragged break occurs when excessive twisting forces are applied to a bone

Condyle

rounded articular projection

Osteoid

secreted by osteoblasts, matrix that sets hardened

Growth Hormone (GH)

secreted by pituitary gland, stimulates chondrocytes in epiphyseal plate and stimulates osteoblasts

Thyroxine

secreted by thyroid gland, stimulates osteoblasts

Calitonin

secreted by thyroid, inhibits osteoclasts, stimulates calcium uptake in bones, increasing calcium blood level

cartilage

semi-rigid connective tissue found on the skeleton in areas where flexibility and smooth surfaces support movement

Fossa

shallow depression

sutural

skull bones that have fused

nutrient foramen

small opening in the middle of the external surface of the diaphysis, through which an artery enters the bone to provide nourishment

sesamoid bone

small, round bone embedded in a tendon; protects the tendon from compressive forces

Facet

smooth, nearly flat articular surface

Estrogen and testosterone effect on bone

stimulates osteoblasts, causing growth spurts and conversion of epiphyseal plate to line

parathyroid hormone

stimulates osteoclasts, increases remodeling and reabsorption of calcium, decreases calcium blood level

Skeletal system function

support, facilitates movement, protects organs, produces blood cells, store minerals & fat

open reduction

surgical exposure of a bone to reset a fracture, skin is broken through by bone

flat bone

thin and curved bone; serves as a point of attachment for muscles and protects internal organs, two layers of sponge bone sandwiched by compact bone called diploe

articular cartilage

thin layer of cartilage covering an epiphysis; reduces friction and acts as a shock absorber

diaphysis

tubular shaft that runs between the proximal and distal ends of a long bone, walls made up of compact bone

osteogenic cell

undifferentiated cell with high mitotic activity; the only bone cells that divide; they differentiate and develop into osteoblasts

articulation

where two bone surfaces meet

epiphysis

wide section at each end of a long bone; filled with spongy bone and red marrow