It's no coincidence that our bodies feel a little creakier as we age. The trillions of cells that make up our skeleton age too, and some change in ways that weaken the very structure of our bones.

Prior to using this narrative, have learners create their own model of a cell in their notebooks using whatever background information or experience they might have. While exploring the narrative, ...

- Muscle cells, also known as myocytes, are specialized cells designed for contraction and force production. Skeletal Muscle Cells: These cells are long, cylindrical, and have a striated (or striped) ...