2 How do you know if something is alive? All living things…Are made up of units called cellsReproduceAre based on a universal genetic codeGrow and developObtain and use materials and energyRespond to the environmentMaintain a stable internal environmentAs a group, living things change over time
3 What is a cell?A collection of living matter enclosed by a barrier that separates the cell from its surrounding.Cells are the smallest units of an organism that can be considered alive.Unicellular = one cellMulti-cellular = many cells
4 Reproduction Producing new organisms Sexual reproduction= cells from 2 different parents unite to produce the first cell of the new organism.Asexual reproduction= the new organism has a single parent
5 Based on a Genetic codeOffspring resemble their parents because they inherited traits from their parents.The directions for inheritance are carried on DNA.This genetic code determines the inherited traits of every organism on earth.
6 Growth and Development All organisms grow during at least part of their livesSingle celled organisms simply grow in sizeMulti-cellular organisms grow by development.
7 Need for materials and energy Organisms use energy and materials to grow and stay aliveMetabolism = the combination of chemical reactions through which an organism builds up or breaks down materials as it carries out its life processes
8 Response to the environment Organisms detect and respond to stimuli from their environment.Stimulus = a signal to which an organism responds
9 Maintaining internal balance Even though conditions in the external environment vary, most organism must keep internal conditions fairly constant to surviveHomeostasis = maintaining internal stability.
10 Evolution A group of organisms will change over time As the environment changes a group of organism will change to adapt through the passing of traits from one generation to the next generation