Ecology

Ecology

• Biosphere- the part of Earth that supports life• Ecosystem- all organisms living in an area and

the nonliving parts of their environment• Ecology- study of interactions that occur among

organisms and their environment• Population- made up of all organisms in an

ecosystem that belong to the same species• Community- all the populations in an

ecosystem

Habitat

• Place where an organism lives– Provides food, safe temperatures, moisture

organism needs to live• Competition- two or more organisms seek the

same resource at the same time

Populations

• Population size- indicates whether a population is healthy and growing– Measured by trap-mark-release or sample count

• Limiting factor- any living or nonliving feature that restricts the number of individuals in a population

• Carrying capacity- largest number of individuals of one species that an ecosystem can support

• Exponential growth- the larger a populations becomes, the faster it grows

Symbiosis

• Any close relationship between species• Mutualism- a symbiotic relationship in which

both species benefit• Commensalism- a symbiotic relationship in

which one organism benefits and the other is not affected

• Parasitism- a symbiotic relationship in which one organisms benefits and the other is harmed

Niche

• An organism’s role in its environment, including its habitat, food, how it avoids danger, finds a mate, cares for young

• Predator- animal that captures and eats other consumers

• Prey- organism that is captured by the predator• Predators limit the size of prey populations,

increasing the number of different species that can live in an ecosystem

Abiotic Factors

• Atmosphere (air)• Water• Soil• Sunlight• climate

Water Cycle

• How water moves from the Earth’s surface to the atmosphere and back to the surface again

• Evaporation- when liquid water changes into water vapor and enters the atmosphere

• Condensation- the process of changing water from a gas to a liquid

Other Cycles

• Nitrogen cycle- the transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to atmosphere

• Carbon cycle- how carbon molecules move between the living and nonliving world

Energy flow

• Matter recycled over and over, but energy is converted from one form to another

• Chemosynthesis- production of energy rich nutrient molecules from chemicals

• Energy stored in the molecules of one organism is transferred to another when one organism becomes food for another organism

Food chain

• Simple wat of showing how matter and energy pass from one organism to another

Food web

• Shows all possible feeding relationships among the organisms in a community

Energy Pyramid

• Shows the amount of energy available at each feeding level in an ecosystem

Ecological succession

• Normal, gradual changes that occur in types of species that live in an area

• Climax community- stable stage of ecological diversity and balance