Cell is the smallest part of living beings. The body is made up of millions of tiny cells. These are the building blocks of the body. A single is too small to be seen with a naked eye. A microscope is needed to see the single cell. There are different kinds of cell. Cells differ in their shapes and functions. For example, skin cells, muscles are made up of muscle cells, bones, teeth, and mails are made up of different jobs. Cell wall, cell membrane, nucleus and cytoplasm are the basic parts of the cell.