In complex organisms often work with other similar cells to perform specific functions,
* Masses of cells working together are
* Examples of tissues include, bone, muscle, and nerves.
* Cells are mostly
and the environment in which all cells live
is wet. (Organisms that have moved onto dry land have to maintain systems
that keep all their cells surrounded by fluid).
* Plants & animals transport water through
systems to ensure that the aquatic environment is provided.
systems and