The process whose specific outcome is the progression of the skeleton over time, from its formation to the mature structure. The skeleton is the bony framework of the body in vertebrates (endoskeleton) or the hard outer envelope of insects (exoskeleton or dermoskeleton).

A series of molecular signals initiated by the binding of an extracellular ligand to a transforming growth factor beta receptor on the surface of a target cell, and ending with regulation of a downstream cellular process, e.g. transcription.

A series of molecular signals initiated by the binding of an extracellular ligand to a transforming growth factor beta receptor on the surface of a target cell, and ending with regulation of a downstream cellular process, e.g. transcription.

Any process that stops, prevents, or reduces the frequency, rate or extent of bone mineralization.

Any process that stops, prevents, or reduces the frequency, rate or extent of chondrocyte differentiation.

The release of transforming growth factor beta (TGF-beta) from its latent state. TGF-beta is secreted as part of a large latent complex (LLC) that is targeted to the extracellular matrix. Release of TGFbeta from its latent state is required for TGFbeta to bind to its receptors, and can occur by a variety of mechanisms.

Any process that activates or increases the frequency, rate or extent of bone resorption.

The continuous turnover of bone matrix and mineral that involves first, an increase in resorption (osteoclastic activity) and later, reactive bone formation (osteoblastic activity). The process of bone remodeling takes place in the adult skeleton at discrete foci. The process ensures the mechanical integrity of the skeleton throughout life and plays an important role in calcium homeostasis. An imbalance in the regulation of bone resorption and bone formation results in many of the metabolic bone diseases, such as osteoporosis.

The process in which bones are generated and organized.

The biological process whose specific outcome is the progression of a lung saccule from an initial condition to its mature state. The lung saccule is the primitive gas exchange portion of the lung composed of type I and type II cells.

Any process that activates or increases the frequency, rate or extent of mesenchymal stem cell proliferation.

Any process that activates or increases the frequency, rate or extent of mesenchymal stem cell differentiation.

The space external to the outermost structure of a cell. For cells without external protective or external encapsulating structures this refers to space outside of the plasma membrane. This term covers the host cell environment outside an intracellular parasite.

A structure lying external to one or more cells, which provides structural support, biochemical or biomechanical cues for cells or tissues.

An extracellular matrix consisting mainly of proteins (especially collagen) and glycosaminoglycans (mostly as proteoglycans) that provides not only essential physical scaffolding for the cellular constituents but can also initiate crucial biochemical and biomechanical cues required for tissue morphogenesis, differentiation and homeostasis. The components are secreted by cells in the vicinity and form a sheet underlying or overlying cells such as endothelial and epithelial cells.