Skeletal System: Bone Structure and Function

These flashcards cover key concepts and terminology related to the skeletal system, bone structure, and function based on the lecture notes.

Skeletal System

A system of bones, cartilage, and ligaments that provides structure, protection, and support in the human body.

Hematopoiesis

The process of blood cell production that occurs in red bone marrow.

Osteoprogenitor cells

Bone stem cells derived from mesenchyme that can differentiate into osteoblasts.

Osteoblasts

Cells that form new bone matrix and are involved in bone growth.

Osteocytes

Mature bone cells that maintain the bone matrix.

Osteoclasts

Large, multinuclear cells that break down bone tissue during the resorption process.

Endosteum

A thin layer of connective tissue that covers all internal surfaces of bone within the medullary cavity.

Epiphyseal plate

A hyaline cartilage plate in the metaphysis of long bones that is the site of bone growth.

Intramembranous ossification

A process of bone development directly from mesenchyme, primarily forming the flat bones of the skull.

Endochondral ossification

The process of bone development from a cartilage model, producing most of the bones in the skeleton.

Calcitonin

A hormone secreted by the thyroid gland that helps regulate calcium levels in the blood.

Parathyroid hormone (PTH)

A hormone released by the parathyroid glands that increases blood calcium levels.

Calcium homeostasis

The regulation of calcium levels in the blood, crucial for various bodily functions like muscle contraction and nerve signaling.

Osteoporosis

A condition characterized by decreased bone density and mass, making the bones fragile and more susceptible to fractures.

Fracture types

Various classifications of bone fractures, including complete, incomplete, simple, compound, and others.

Fibrocartilaginous callus

A temporary structure that forms during the healing process of a bone fracture before bone regrowth occurs.

Bone matrix

An extracellular matrix made up of organic and inorganic components that provides structural support to bone tissue.

Periosteum

A tough, fibrous membrane covering the outer surface of bone, providing protection and a point of attachment for muscles and tendons, and containing osteoblasts.

Compact bone

Dense, rigid bone tissue that forms the outer layer of most bones, providing strength and protection.

Spongy bone (Cancellous bone)

Porous bone tissue found inside bones, containing red bone marrow in its spaces, and providing strength with reduced weight.

Osteon (Haversian system)

The basic structural unit of compact bone, consisting of concentric layers of bone matrix (lamellae) around a central canal containing blood vessels and nerves.

Red bone marrow

Soft tissue located in the spongy bone of certain bones (e.g., hip, sternum, vertebrae, cranial bones, and epiphyses of long bones), primarily responsible for hematopoiesis.

Yellow bone marrow

Adipose tissue found in the medullary cavity of long bones, functioning primarily as a site for fat storage.

Medullary cavity

The central cavity within the diaphysis (shaft) of long bones, containing yellow bone marrow in adults.

Appositional growth

The process by which bones increase in diameter and thickness, involvinog the deposition of new bone matrix on the surface by osteoblasts under the periosteum.

Bone remodeling

The continuous process of bone degradation