 Biology – The study of life, living things ◦ Bio- = life ◦ –ology= study of

 To be considered living things it must possess all of the characteristics of life.  Some non-living things may possess some of the characteristics.

◦ Unicellular=a single cell ◦ Multicellular= more than a single cell

◦ Sexual reproduction= DNA from two parents; offspring different than parent ◦ Asexual reproduction=single parent; offspring the same as parent

 DNA

 Become larger  Change over time ◦ Differentiation=cells begin to look different and perform different functions.

 Metabolism=chemical reactions in the body that build and break down materials  Generally: ◦ plants=photosynthesis ◦ animals=eating

 Stimulus=a signal to which we respond (bell ringing)  Response=a reaction to a stimulus (move to next class)

 Homeostasis=internal conditions remain constant (lizards sun themselves)

 Evolution

 Zoologists= study of animals  Botanists=study of plants  Paleontologists= study of ancient life

 (from most simple to most complex)

 Molecules  Groups of atoms Examples : Water DNA

 Cells  Smallest unit of life Example: Nerve cell

 Groups of Cells  Tissues, organs, and organ systems Example: Nervous tissue Brain Nervous system

 Organism  Individual living thing Example: Bison

 Population  Group of organisms of one type that live in the same area Bison herd

 Community  Populations that live together in a defined area Hawk, snake, bison, prairie dog, grass

Copyright Pearson Prentice Hall  Ecosystem  Community and its nonliving surroundings Hawk, snake, bison, prairie dog, grass, stream, rocks, air

 Biosphere  The part of Earth that contains all ecosystems