Crossword Puzzle Word CrossOnline version This activity is about the Biological Organization of Life. This will measure your understanding in the lesson. by Avie Wilson 1 Group of single-celled or multi-celled individuals individuals of a species in a given area. 2 All populations of all species in a specified area. 3 A community interacting with its physical environment through the transfer of energy and materials. 4 The sum of all ecosystems. 5 Atoms joined in chemical bond. 6 Organized array of cells. 7 Structural unit of interacting tissues. 8 Fundamental units of all substances. 9 The smallest unit of life 4 9 2 6 5 7 8