An explanation of how cells make up tissues which in turn make up organs. The diversity of cells in the human body is mentioned. Using muscle cells as an example, it is then explained how cells are adapted to their function. A group of cells working together is defined as a tissue and several tissues working together comprise an organ. The heart is used as an example of an organ which is made up from muscle and valve tissue.
Students can draw diagrams showing how cells, tissues and organs are different but connected. The class could choose a specific organism, listing its organs and investigating how they grow and develop.