Skeletal System Concise Complete Review

Comprehensive vocabulary flashcards covering skeletal system structure, bone growth and repair, axial and appendicular skeleton anatomy, calcium regulation, and life-span changes based on Hole's Human Anatomy & Physiology.

Long Bones

Bones that are long and narrow with expanded ends.

Short Bones

Cube-like bones with length roughly equal to width, including round sesamoid bones embedded in tendons.

Flat Bones

Plate-like bones with broad surfaces.

Irregular Bones

Bones with a variety of shapes, most of which are connected to several other bones.

Epiphysis

The expanded end of a long bone.

Osteocytes

Mature bone cells.

Lacunae

Chambers occupied by osteocytes in bone tissue.

Canaliculi

Tiny passageways through which cell processes of osteocytes exchange nutrients and wastes.

Compact Bone

Strong, solid, weight-bearing bone structure consisting of cylindrical units called osteons that resist compression.

Hydroxyapatite

Calcium phosphate crystals that constitute the most abundant inorganic mineral salt in the bone matrix.

Calcium Homeostasis

The regulation of blood calcium levels by Parathyroid hormone and Calcitonin due to calcium's role in nerve impulse conduction and muscle contraction.

Intramembranous Bones

Bones that form between sheets of primitive connective tissue, such as flat skull bones, clavicles, sternum, and some facial bones.

Endochondral Bones

Bones that form from hyaline cartilage models, including long bones and most of the skeleton.

Osteogenesis imperfecta

A hereditary collagen defect in which forming bones are brittle and a fetus may suffer many bone fractures.

Primary Ossification Center

Area in the center of the diaphysis where bone tissue first replaces cartilage.

Secondary Ossification Center

Area of the epiphyses where spongy bone forms later in development.

Epiphyseal Plate

A band of cartilage that persists between primary and secondary ossification centers and allows a long bone to grow in length.

Zone of Resting Cartilage

Layer of the epiphyseal plate closest to the end of the epiphysis containing resting cells that anchor the plate to the epiphysis.

Zone of Proliferating Cartilage

Layer of the epiphyseal plate composed of rows of young cells undergoing mitosis.

Zone of Hypertrophic Cartilage

Layer of the epiphyseal plate with older cells that thicken the plate and lengthen the bone as matrix calcifies and chondrocytes die.

Zone of Calcified Cartilage

Thin layer of the epiphyseal plate consisting of dead cartilage cells and calcified matrix.

Bone Resorption

The removal of bone matrix by osteoclasts.

Bone Deposition

The formation of bone tissue by osteoblasts.

Bone Remodeling

The continuous life-long process of bone deposition and resorption on endosteum and periosteum surfaces, replacing 10% to 20% of the skeleton each year.

Pituitary Dwarfism

A condition resulting from growth hormone insufficiency in a child.

Acromegaly

A condition caused by an excess of growth hormone in an adult.

Traumatic Fracture

A fracture caused by an injury.

Pathologic Fracture

A spontaneous fracture caused by disease.

Simple Fracture

A closed fracture protected by uninjured skin or mucous membrane.

Compound Fracture

An open fracture in which the bone is exposed to the outside through a break in the skin or mucous membrane.

Greenstick Fracture

An incomplete fracture occurring on the convex surface of the bend in a bone.

Fissured Fracture

An incomplete longitudinal break in a bone.

Comminuted Fracture

A complete fracture that fragments the bone.

Transverse Fracture

A complete fracture occurring at a right angle to the axis of the bone.

Oblique Fracture

A fracture occurring at an angle other than a right angle to the axis of the bone.

Spiral Fracture

A fracture caused by excessive twisting of a bone.

Hematoma

A large blood clot formed right after a fracture occurs.

Cartilaginous Callus

A soft callus formed during fracture repair when fibrocartilage is produced and osteoblasts invade to make spongy bone.

Bony Callus

A hard callus that replaces fibrocartilage during bone fracture repair.

Fragility Fracture

A fracture occurring after a fall from less than standing height, serving as a sign of low bone density.

Osteopenia

Bone loss that occurs when osteoclasts remove more bone than osteoblasts deposit, which may progress to osteoporosis.

Osteoporosis

Severe bone loss that leaves spaces and canals in bone, weakening them and increasing fracture risk.

Sutural Bones

Extra bones located in the sutures between major skull bones, also known as wormian bones.

Axial Skeleton

Division of the skeleton comprising 80 bones, including the skull, middle ear bones, hyoid bone, vertebral column, and thoracic cage.

Cranium

Structure composed of 8 bones that encloses and protects the brain.

Foramen Magnum

Large opening in the occipital bone that serves as a passageway for the brain to meet the spinal cord.

Occipital Condyles

Processes on the occipital bone that articulate with the atlas.

Sphenoid Bone

Bone that forms the base of the cranium, sides of the skull, and floors and sides of the eye orbits, containing the sella turcica.

Ethmoid Bone

Bone situated in front of the sphenoid that forms the roof and walls of the nasal cavity, floor of the cranium, and wall of eye orbits.

Cribriform Plates

Plates of the ethmoid bone containing openings for axons of olfactory (smell) neurons.

Perpendicular Plate of Ethmoid Bone

Structure of the ethmoid bone that forms the main portion of the nasal septum.

Maxillae

Paired bones forming the upper jaw, anterior hard palate, floors of eye orbits, and sides and floors of the nasal cavity.

Cleft Palate

Condition resulting from incomplete fusion of the palatine processes during fetal development.

Palatine Bones

L-shaped bones located behind the maxillae that form the posterior section of the hard palate and floor/lateral walls of the nasal cavity.

Vomer Bone

Single bone located along the midline of the nasal cavity that forms the inferior portion of the nasal septum.

Inferior Nasal Conchae

Scroll-shaped bones extending inward from lateral walls of the nasal cavity that support mucous membranes.

Mandible

The lower jawbone, which is the only movable bone of the facial skeleton.

Fontanels

Fibrous membranes in an infantile skull connecting cranial bones where intramembranous ossification is incomplete.

Vertebral Column

Central axis of the skeleton consisting of vertebrae separated by intervertebral discs that supports the head and trunk and protects the spinal cord.

Transverse Foramina

Openings in the transverse processes of cervical vertebrae that serve as passageways for blood vessels leading to the brain.

Vertebra Prominens

The seventh cervical vertebra (C7), which has a spinous process longer than those of other cervical vertebrae.

Sacrum

Triangular structure at the base of the vertebral column composed of 5 fused vertebrae.

Coccyx

The tailbone, which typically consists of 4 vertebrae that fuse between ages 25 and 30.

True Ribs

The first 7 pairs of ribs (vertebrosternal ribs) that connect directly to the sternum.

False Ribs

The lower 5 pairs of ribs that do not connect directly to the sternum.

Floating Ribs

The lower 2 pairs of false ribs (vertebral ribs) that have no connection to the sternum.

Pectoral Girdle

Structure consisting of 2 clavicles and 2 scapulae that supports the upper limbs and provides muscle attachment sites.

Humerus

The single bone of the upper arm.

Carpal Bones

The 8 wrist bones: scaphoid, lunate, triquetrum, pisiform, hamate, capitate, trapezoid, and trapezium.

Pelvic Girdle

Structure composed of 2 hip bones that supports the trunk, protects internal organs, and transmits body weight to lower limbs.

Ilium

The largest and most superior part of the hip bone.

Ischium

The L-shaped lowest portion of the hip bone that supports body weight while sitting.

Female Pelvis

Pelvic structure adapted for childbearing, characterized by more flared iliac bones and broader hips than a male pelvis.

Femur

The thigh bone, which is the longest bone in the human body.

Tibia

The shin bone, which is the larger, medial weight-bearing bone of the leg.

Fibula

A long, slender, non-weight bearing bone located on the lateral side of the tibia.

Calcaneus

The heel bone, which is one of seven tarsal bones.