Anatomy and Physiology: Bone Tissue, Skeletal System, and Articulations

Comprehensive vocabulary flashcards covering bone structure, skeletal anatomy, and joint classifications and movements from Chapters 7, 8, and 9.

Compact Bone

Dense, solid bone tissue composed of microscopic osteons that forms the sturdy external layer of bones.

Spongy Bone

Porous bone tissue composed of an open lattice of narrow plates called trabeculae, located internally within bones.

Hematopoiesis

The process of blood cell formation that takes place within red bone marrow.

Diaphysis

The elongated, cylindrical shaft of a long bone that provides leverage and major support.

Epiphysis

The expanded, knobby region located at each end of a long bone, categorized as either proximal or distal.

Metaphysis

The region of a mature bone where it widens and transfers weight between the diaphysis and epiphysis.

Epiphyseal Plate

A layer of hyaline cartilage located in the metaphysis that allows for lengthwise (interstitial) bone growth in children and adolescents.

Epiphyseal Line

The thin internal line of compact bone in adults that represents the remnant of the fully ossified epiphyseal plate.

Periosteum

A tough, vascular, and innervated connective tissue sheath covering the outer surface of bone except where articular cartilage is present.

Endosteum

An incomplete cellular layer that lines the internal marrow cavities, canals, and trabecular surfaces of bones.

Diploe

The internal layer of spongy bone sandwiched between two layers of compact bone within flat skull bones.

Nutrient Foramen

A small opening or hole through the compact bone that allows entry and exit for nutrient blood vessels and nerves.

Osteon

The basic functional and structural unit of mature compact bone, displaying a concentric, round, bull's-eye target appearance (also called a Haversian system).

Trabeculae

An open lattice of crisscrossing narrow rods and plates of bone tissue that characterizes spongy bone.

Somatotropin

A growth hormone that promotes bone elongation by directly stimulating cartilage growth within the epiphyseal plate.

Achondroplasia

A genetic condition characterized by abnormal conversion of hyaline cartilage to bone, resulting in disproportionate dwarfism.

Osteopenia

A condition characterized by a mild to moderate reduction in bone mass due to diminished bone mineral density.

Osteoporosis

A severe bone disorder marked by significant loss of bone matrix and density, resulting in porous, fragile bones vulnerable to fracture.

Occipital Condyles

Smooth, rounded projections on the occipital bone that articulate directly with the first cervical vertebra (atlas).

Sella Turcica

A saddle-shaped bony depression in the sphenoid bone of the skull that houses and protects the pituitary gland.

Hyoid Bone

A U-shaped bone located in the anterior neck that is unique for being the only free-floating bone in the body that does not articulate with any other bone.

Atlas (C1)

The first cervical vertebra, which lacks a body and spinous process, articulates with the occipital condyles, and allows the head to nod 'yes.'

Axis (C2)

The second cervical vertebra, featuring a prominent vertical projection (dens) that allows the head to rotate or shake 'no.'

Dens

The peg-like vertical projection of the axis (C2) that acts as a body and pivot point for the atlas (C1).

Interosseous Membrane

A broad, dense sheet of fibrous connective tissue that stabilizes and keeps adjacent long bones (radius/ulna and tibia/fibula) a fixed distance apart.

Pollex

The anatomical term for the thumb (digit I), which is composed of only two phalanges.

Hallux

The anatomical term for the great toe (digit I), which is composed of only two phalanges.

Os Coxae

The hip bone formed by the fusion of three individual bones: the ilium, ischium, and pubis.

Pubic Symphysis

The anterior fibrocartilaginous joint that unites the left and right pubic bones of the pelvis.

Sutures

Immovable (synarthrotic) fibrous joints that interlock the flat bones of the skull.

Syndesmoses

Fibrous joints in which articulating bones are joined together by ligaments or broad sheets of fibrous tissue (such as an interosseous membrane).

Gomphoses

Specialized 'peg-in-socket' fibrous joints that secure the roots of teeth into the alveolar sockets of the maxillae and mandible.

Synchondroses

Immovable (synarthrotic) cartilaginous joints where articulating bones are united specifically by hyaline cartilage.

Symphyses

Strong, slightly moveable (amphiarthrotic) cartilaginous joints where articulating bones are connected by a broad pad of fibrocartilage.

Diarthrosis

A functional classification describing a freely moveable joint, characteristic of all synovial joints.

Amphiarthrosis

A functional classification describing a joint that allows slight or limited movement.

Synarthrosis

A functional classification describing an immovable joint.

Origin

The skeletal attachment site of a muscle that remains relatively stationary or fixed during muscle contraction.

Insertion

The mobile skeletal attachment site of a muscle that is pulled toward the origin during muscle contraction.

Flexion

An angular movement that decreases the angle between articulating bones in the sagittal plane.

Extension

An angular movement that increases the angle between articulating bones in the sagittal plane.

Abduction

A lateral movement of a bone or limb away from the midline of the body in the coronal plane.

Adduction

A medial movement of a bone or limb toward the midline of the body in the coronal plane.

Circumduction

A continuous sequence of flexion, abduction, extension, and adduction where the proximal end of a limb remains stationary while the distal end moves in a circle.

Supination

Rotational movement of the forearm that rotates the radius laterally so that the palm faces anteriorly or superiorly.

Pronation

Rotational movement of the forearm that crosses the radius over the ulna so that the palm faces posteriorly or inferiorly.

Dorsiflexion

Movement at the talocrural (ankle) joint where the superior surface of the foot is elevated toward the anterior leg.

Plantar Flexion

Movement at the talocrural (ankle) joint where the foot is depressed and the toes point downward.

Inversion

Specialized movement of the foot at the intertarsal joints that turns the sole of the foot medially toward the midline.

Eversion

Specialized movement of the foot at the intertarsal joints that turns the sole of the foot laterally away from the midline.

Opposition

Specialized movement at the carpometacarpal joint that brings the pad of the thumb across the palm to contact the tips of the fingers.