The Skeletal System – Bone Tissue

A set of vocabulary flashcards covering key concepts in the study of the skeletal system and bone tissue.

Skeletal system

An organ system composed of bones, cartilages, and ligaments that supports and protects the body and facilitates movement.

Functions of the skeletal system

Support, protection, movement, mineral storage, blood cell formation.

Long bones

Bones that are longer than they are wide; examples include femur and humerus.

Short bones

Bones that are roughly cube-shaped; examples include carpals and tarsals.

Flat bones

Bones that are thin and flat; examples include the skull, ribs, and sternum.

Irregular bones

Bones with complex shapes that do not fit into other categories; an example is the vertebrae.

Sesamoid bones

Bones that are embedded in tendons; an example is the patella.

Diaphysis

The long shaft of a long bone made of compact bone.

Epiphysis

The end part of a long bone, which contains spongy bone.

Medullary cavity

The cavity within a long bone that contains yellow marrow.

Periosteum

A fibrous membrane that covers and protects the bone, containing an osteogenic layer.

Endosteum

A thin membrane lining the medullary cavity of a bone.

Articular cartilage

Cartilage that covers the ends of bones in a joint.

Bone markings

Surface features of bones that serve various functions, including muscle attachment and articulation.

Osteons

The structural unit of compact bone, consisting of concentric lamellae and a central canal.

Osteoblasts

Bone-forming cells that produce the bone matrix.

Osteocytes

Mature bone cells that maintain the bone matrix.

Osteoclasts

Cells that break down bone tissue during bone resorption.

Bone matrix components

Made up of organic components, such as collagen, for flexibility, and inorganic components, such as hydroxyapatite, for hardness.

Intramembranous ossification

The process by which flat bones are formed directly from mesenchyme.

Endochondral ossification

The process by which long bones are formed through a cartilage model.

Epiphyseal plate

A cartilaginous growth plate that allows for the lengthwise growth of long bones.

Bone remodeling

The ongoing process of bone formation and breakdown to adapt to stress and hormonal changes.

Calcium homeostasis

The regulation of calcium levels in the blood, influenced by hormones like parathyroid hormone (PTH) and calcitonin.

Osteoporosis

A condition characterized by a decrease in bone density and mass, leading to an increased risk of fractures.

Rickets

A disease caused by vitamin D deficiency, leading to soft and weakened bones.

Osteomalacia

A condition of softened bones due to mineral deficiencies, particularly vitamin D.