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Unifying Themes in Biology

Ch.1 main page
Scientific Method
Unifying Themes
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There are 6 Themes that this book and the study of Biology will continually refer back to.  These themes give guidelines in which to define "LIFE."   These are:

1.  Cell structure and function - All cells are composed of cells.  Some are unicellular and self contained while some are multicellular  with each cell type performing a generalized life function.  All cells have membranes that surround them and all contain a nucleus that contain DNA that controls its activities

2.  Stability and Homeostasis - Homeostasis is maintaining a constant internal condition.  All cells must control its' internal environment and act to change it if it is to survive.  A cell must also be able to "sense" any change in its' environment and react accordingly

3.  Heredity - Heredity is the transmission of "developmental instructions from parents to offspring.  If damage (mutation) occurs it must correct the change or pass it down to its offspring.  Mutation is what allows evolution to take place.

4.  Evolution - Inherited change in a populations characteristics over time. 

5.  Interdependence - All things rely on each other either directly or indirectly

6.  Matter energy and organization - All organisms are composed of atoms, which assemble into molecules.  cells are made of molecules.  All life requires energy and life is organized into many levels.