Dictionary MAIN PAGE Text & Grap

Cell - Cells are the basic unit of life. All living things are made up of cells connected by electrical current. Many processes and parts of human cells are not so different from those in trees. Yet, animal cells have thin boundaries. Tree wood cells have thick, tough boundaries or walls. Animal tissue will not support itself. Animals require skin and bones to keep cells in place. Every splinter of wood is self - supporting. Cell walls of wood are made of cellulose, lignin, and hemicelluloses. Thin boundaries of animal cells allow them to move. Animals move away from agents and situations that threaten their survival. Trees cannot move. Trees grow where they find themselves, adapt or die. Trees planted incorrectly are sentences to an early death. See “ecosystem” and “wood cells”.