II. Needs of an Organism

A. Water 1. Most important need is fresh water 2. Needed for all living things 3. If live in an aquatic environment have many additional factor a. Temperature, nutrients, dissolved oxygen, etc. 1. Warm water contains less oxygen but more nutrients

B. Food and/or Energy 1. Sun is the main source a. Plants make nutrients from sunlight that go up through environment to other organisms 2. Harmful items in food or environment can remain in organisms indefinitely though

C. Living Space 1. Competition for the previous two needs results in protection of a territory 2. Mark territory in 3 ways: a. Scent b. Visual clues c. Sound 3. Higher in the food chain= more territory needed

D. Climate 1. All living things are designed to live within a certain climatic range 2. Can hibernate during cold or estivate during the heat 3. Warm blooded animals do better with colder climates a. However, need more food 1. 10x’s as much as same size cold blooded animal