ECOLOGY interaction between and among organisms and their environment or surroundings

Three basic approaches to studying the living world: Observing Experimenting Modeling

What makes up an environment?? Everything living and nonliving that supports life living: nonliving: The food, shelter, and ability to reproduce

Environment must be able to support life. If it can’t the organisms will die. Here on Earth, everything on the planet and around the planet constitutes the environment. This everything is what we call the BIOSPHERE. The biosphere includes all parts of the planet: land water = hydrosphere 11 km below surface of oceans air = atmosphere 8 km above the surface of the Earth

biosphere

Biome: There are two types of biomes: aquatic terrestrial

The biomes of South America can support different and numerous Life forms. This constitutes ecosystems. An ecosystem is a collection of all organisms that can live in that Biome. An ecosystem includes living and nonliving components.

Community: all organisms co existing in an ecosystem Population: all the same species Species: a group of organisms so similar that they can breed and produce fertile offspring. Individual: one within a species

All living things require energy All living things require energy. The amount of energy in the biosphere remains constant. The Law of Conservation of Matter and Energy: Autotrophs Heterotrophs Detritovores Photosynthesis chemosynthesis

Energy flows in one direction: from the sun or inorganic compounds to autotrophs and then to heterotrophs. Food chains pass energy from producers to consumers. Food webs:

Each level is referred to as a trophic level. Only about 10% of the energy available in one trophic level is transferred to the next trophic level. Energy within each level is used to Support life functions and some of the energy is lost as heat energy To the environment

Biomass: the amount of living tissue supported by each trophic level. Similar to the energy pyramid, the greatest amount of biomass is at the bottom of the pyramid.

In a pyramid of numbers, the relative size and number of organisms able to live at any given trophic level.