1. Ecology Organisms obtain food, water, Shelter and other need to live, grow and reproduce from its environment Different needs----Different Habitats Living Part of Habitat Nonliving parts of Habitat

2. Abiotic Factors in Habitat Water---needed for life processes---Photosynthesis and Metabolism Sunlight---ultimate source of all energy Oxygen/Carbon Dioxide---needed to carry out life processes Temperature---cannot live in extremes---some animals alter environments to survive Soil---mixture of rock fragments, nutrients, air, water and decaying matter

3. Live in Populations--- members of one species in a particular area Communities--- all different populations that live and interact together Ecosystems---organisms that live in a particular area along with their nonliving (abiotic) surroundings Ecology- study of how living things interact with each other and their environment.

4. Define Population--- Determining Population Size Method Description What causes changes in populations? Births---Deaths Immigration---Emigration How do you calculate population density? What is a limiting factor? Name some. Page 711 Direct Observation Count all members of a population Indirect Observation Observe evidence of or signs of organisms Sampling Estimateapproximate number Count population in a small area/multiply to find Number in large area Mark and Recapture Catch without harming---count---mark By some method---release---return and Recapturecount those with and without Markingsuse formula to estimate pop into out Population = Number Individuals 120 students Density Unit of Area 4 classrooms 30 students per class Something that causes a population to decrease Food, water, temperature, rainfall, space