A closer look at some trends in youth sport participation. This is an excerpt from Social Issues in Sport, Second Edition, by Ronald B. Woods, PhD. With participation in youth sport at an all-time high, it would appear that things are rosy in the sporting world of kids. In 2000, the number of American youth who played on at least one organized sport team was found to be 54% of kids between ages 6 and 17 (American Sports Data, Inc. 2005).
The integrity of tissues is also dependent on the adhesion, by CAMs, of cells to cells and cells to the Extracellular Matrix. Extracellular matrix (ECM) All cells in solid tissue are surrounded by extracellular matrix. Both plants and animals have ECM. The cell wall of plant cells is a type of extracellular matrix.n animals, the ECM can surround cells as fibrils that contact the cells on all sides, or as a sheet called the basement membrane that cells âsit onâ. Cells in animals are also linked directly to each other by cell adhesion molecules (CAMs) at the cell surface.
Epithelial cells are held together by strong anchoring (zonula adherens) junctions. The adherens junction lies below the tight junction (occluding junction). In the gap (about 15-20nm) between the two cells, there is a protein called cadherin-a cell membrane glycoprotein.(The type of cadherin found here is E-cadherin). occluding junctions (zonula occludens or tight junctions). 2  adhering junctions (zonula adherens). 3  desmosomes (macula adherens). 4  There are also ' hemidesmosomes ' that lie on the basal membrane, to help stick the cells to the underlying basal lamina.