1. Studying Life

2.  “ Bios” = life  “Ology” = the study of something  Biology = study the of life  Biologists = people who study biology  Study interactions in environment, study problems and propose solutions

3.  No single characteristic is enough to describe a living thing.  Also, some nonliving things share one or more traits with living things.  Example = mechanical toys, cars, and clouds move around.  Despite these difficulties, it is possible to describe what most living things have in common

4.  Living things share these characteristics:  Living things are made up of cells (unicellular vs. multicellular)  Reproduction  Based on a universal genetic code  Growth & Development  Response to stimuli  Homeostasis– regulation of internal environment  Use materials & energy  Change over time or Adapt

5.  Living things may be studied on many different levels.  The levels are (from the smallest group to the largest group):  Molecules  Cells  Groups of cells (tissues, organs, & organ systems)  Organism (individual living thing)  Population (group of one type of organism)  Community (Populations that live together in one area)  Ecosystem (Living & nonliving things in an area)  Biosphere (Part of the Earth that contains all ecosystems)