EcologyOrganisms 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

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

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.

Define Population---

Determining Population SizeMethod Description

What causes changes in populations?

Births---Deaths Immigration---Emigration

How do you calculate population density?

What is a limiting factor?

Name some.

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Direct Observation Count all members of a population

Indirect Observation Observe evidence of or signs of organisms

SamplingEstimate—approximate numberCount population in a small area/multiply to findNumber in large area

Mark andRecapture

Catch without harming---count---markBy some method---release---return and Recapture—count those with and withoutMarkings—use formula to estimate pop

into out

Population = Number Individuals 120 studentsDensity Unit of Area 4 classrooms 30 students per class

Something that causes a population to decrease

Food, water, temperature, rainfall, space