Ecology

1. Ecology Organism--- Living Thing Organisms obtain food, water, Shelter and other need to live, grow and reproduce from its environment Different needs----Different Habitats Habitat Biotic Factors Abiotic Factors Nonliving parts of Habitat Living Part 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. Ecology-study of how living things interact with each other and their environment. Organisms Share their Habitat 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

4. Studying Populations Define Population--- Page 711 Determining Population Size Method Description Count all members of a population Direct Observation Observe evidence of or signs of organisms Indirect Observation Estimate—approximate number Count population in a small area/multiply to find Number in large area Sampling Catch without harming---count---mark By some method---release---return and Recapture—count those with and without Markings—use formula to estimate pop Mark and Recapture What causes changes in populations? Births---Deaths Immigration---Emigration How do you calculate population density? What is a limiting factor? Name some. out into 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