Ecology the study of living things and their environment

Living Things are Organized Organism Population Community

A HABITAT A place where a plant or animal lives in the community Organisms are affected by the things in their environment.  Biotic Factors- living things  Ex. Predators and Prey  Abiotic Factors- Nonliving things  Sunlight, rain, snow, etc…

An organism lives in its habitat and has a job there too. An organism’s role in the community is called its NICHE There are 3 main roles an organism can play in a community.

1. PRODUCERS  Autotrophs (a.ka. Plants)  Photosynthesis Converts CO 2 and H 2 O into Sugar Give off Oxygen as bi-product

2. CONSUMERS Heterotrophs eat other organisms to acquire energy  HERBIVORE:  Eats Plants  Primary Consumer  CARNIVORE:  “Meat Eater”  Secondary Consumer

3. DECOMPOSERS Decomposers break down dead materials Examples:  Fungi  Bacteria Decomposers have a very important job they break materials into simpler chemicals.

The Food Chain A pathway of energy and materials through a community. ARROWS INDICATE WHICH WAY THE ENERGY FLOWS

A Food Web Interconnecte d food chains of a community Again, arrows show flow of energy

Less than 1% of the sun’s energy is converted into chemical energy by producers!

Energy in the Community  The ultimate source of energy is the sun.  Energy FLOWS through a community.  Producers have the most energy  At each step of the food chain less and less energy is available.  Only 10% of energy is transferred to the next level.

Ecological Pyramids A diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or food web There are 3 different kinds of pyramids: 1. Energy Pyramids 2. Biomass Pyramids 3. Pyramids of Numbers

Energy Pyramid Shows the relative amounts of energy available at each trophic level. “The Rule of Ten”  Only about 10% of the energy available within one trophic level is transferred to organisms at the next trophic level.  90% of an organism’s energy is used for:  Movement  Respiration  Reproduction  Lost as heat

Energy Pyramid Example

Pyramid of Numbers

We know what a happens to energy in trophic levels… So what happens to TOXINS?

The accumulation of a contaminant or toxin in or on an organism from all sources (e.g., food, water, air) Compounds accumulate in living things any time they are taken up and stored faster than they are broken down (metabolized) or excreted.Bioaccumulation

Biomagnification the increase in concentration of toxin as it passes through successive levels of the food web toxins accumulates at higher levels in organisms that are higher in the food chain