Skeletal System and Articulations

Vocabulary flashcards covering skeletal anatomy, bone structures, histology, vertebrae, and joint types.

Red bone marrow

The tissue where most blood cells are produced.

Osseous tissue

A type of connective tissue that makes up bone.

Epiphyseal line

The remnant of the growth plate that separates the epiphysis from the diaphysis in adult bones.

Epiphyses

The expanded ends of long bones.

Osteoblasts

Bone-forming cells that deposit new bone.

Spongy bone

Bone tissue characterized by the presence of spicules and trabeculae.

Bone remodeling

The lifelong process of breaking down old bone and replacing it with new bone.

Appositional growth

The growth of bones in thickness or diameter, occurring at the outer surface beneath the periosteum.

Osteoporosis

A condition resulting from a decline in bone density.

Osteoclasts

Cells that break down bone tissue.

Soft callus

A fibrocartilaginous structure that temporarily stabilizes a healing fracture.

Diaphysis

The shaft of a long bone.

Metaphysis

The region between the diaphysis and epiphysis containing the growth plate in growing bones.

Periosteum

The connective tissue membrane covering the outer surface of bones.

Medullary cavity

The hollow space inside the shaft of a long bone containing bone marrow.

Endosteum

The membrane lining the internal surfaces of bones.

Axial skeleton

The skeletal division consisting of the skull, vertebral column, ribs, sternum, hyoid bone, and auditory ossicles.

Appendicular skeleton

The skeletal division consisting of the pectoral girdles, upper limbs, pelvic girdle, and lower limbs.

Condyle

A rounded articular prominence that forms a joint with another bone.

Process

Any bony prominence or projection.

Foramen

An opening through a bone that usually allows nerves and blood vessels to pass.

Fossa

A depression or hollow in a bone.

Tuberosity

A large, roughened bony projection.

Crest

A narrow ridge of bone.

Head (of a bone)

A rounded articular end of a bone, often supported by a neck.

Sutures

Immovable fibrous joints connecting most skull bones.

Maxillae

The facial bones that form most of the hard palate.

Scoliosis

The most common spinal curvature deformity, characterized by an abnormal lateral curvature of the spine.

Sternum

A bone belonging to the thoracic cage composed of three parts: the manubrium, body, and xiphoid process.

True ribs

Ribs $1$ through $7$, which attach directly to the sternum through their own costal cartilages.

False ribs

Ribs $8$ through $12$, which do not attach directly to the sternum through their own costal cartilages.

Floating ribs

Ribs $11$ and $12$, which have no anterior attachment to the sternum.

Atlas

The first cervical vertebra (C1), which supports the skull.

Axis

The second cervical vertebra (C2), which allows the head to rotate.

Sacrum

A structure formed from $5$ fused vertebrae that constitutes the posterior part of the pelvis.

Coccyx

The tailbone, typically formed from $4$ fused vertebrae.

Metacarpals

The bones that form the palm of the hand.

Radius

The lateral forearm bone in the anatomical position.

Ulna

The medial forearm bone in the anatomical position.

Patella

The kneecap, which is an example of a sesamoid bone located within the quadriceps tendon.

Tibia

The lower leg bone that bears most of the body's weight.

Fibula

The lower leg bone that is not a primary weight-bearing bone.

Acetabulum

The socket of the hip bone that articulates with the head of the femur.

Articulation

A point where two bones meet.

Synostosis

A bony fusion joint that allows the least movement.

Synovial joint

A structural category of joints that generally allows the greatest movement.

Syndesmosis

A fibrous joint where bones are connected by ligaments or an interosseous membrane, such as between the shafts of the radius and ulna.

Gomphosis

A fibrous joint that anchors a tooth in its socket.

Meniscus

A fibrocartilage pad within a joint that improves fit, stability, and shock absorption.

Articular cartilage

Smooth hyaline cartilage covering the ends of bones at synovial joints.

Bursa

A fluid-filled sac that reduces friction between moving tissues.

Articular capsule

A connective tissue enclosure surrounding a synovial joint that can be reinforced by ligaments and tendons.

Talocrural joint

The joint formed by the tibia, fibula, and talus.

Acetabular labrum

A structure that deepens the hip socket and improves joint stability.