1.A population is a group of organisms of the same species which occupies a given area. 2.Organisms do not live solitary lives in isolation from other members of their species 3.Organisms are composed of cells but not simply put cells together(Cells in different tissues have different functions) 6 6 1. A population is a group of organisms of the same species which occupies a given area. 2. Organisms do not live solitary lives in isolation from other members of their species 3. Organisms are composed of cells but not simply put cells together (Cells in different tissues have different functions)