Ecology

What is Ecology? The study of organisms interacting with each other and their environment. In what ways do organisms interact?

What does it mean to be alive? Ability to reproduce Made of cells Heredity Homeostasis Metabolism Growth and development Responsiveness

What makes up the Environment Habitat – the physical environment Abiotic: non-living things (not the same as “dead”) Community – all the organisms living in an area Biotic: Living organisms

Organism A single living thing

Population A group of organisms of the same species living in the same place at the same time.

Community All of the species living in an area

Ecosystem The combination of living and non-living in an area – the habitat and community together.

Biome An ecosystem that is spread over a large area

What is the key element in an ecosystem? It’s all about energy. All organisms need some sort of energy to be alive. The property of life that this refers to is metabolism. The ultimate source of energy for life on Earth is the sun. Energy is captured from sun by organisms called autotrophs. They may also be referred to as producers.

The Flow of Energy Other organisms get the energy they need by eating another living thing. These organisms are called heterotrophs or consumers. In ecology, organisms are ranked by what type of organism they eat.

Food chain The arrows in a food chain (or food web) show the flow of energy !!

But wait….there’s more!! Food chains show a linear flow of energy in an ecosystem, one organism’s (food) relationship to the next. But what if an organism eats more than one thing (most do!)?

The resulting connected food chains are called a Food Web.

The flow of energy, continued… The sun’s radiant energy is absorbed by plants through a process called photosynthesis. The energy stored in the plant is broken down into useful energy by the animals that eat them by a process called cellular respiration. For all of the sunlight that hits Earth’s surface, only 1% is absorbed by producers. Only 10% of the energy in any trophic level is available to the next level. Where does the rest of the energy go?