Chapter 2

Biospheres Made up of Atmosphere gases Lithosphere earths outer layer Hydrosphere Water Gaia Hypothesis Earth behaves like a living organism

All living organisms sharing a region and interact with each other and their non-living environment Abiotic factors -- Not living Wind, water, temperature etc. Biotic factors -- Living All organisms Predator, prey, competitors Their remains, products or waste Sustainability Ability to maintain characteristics over a long period of time Natural ecological conditions and processes

Recall: Electromagnetic Spectrum Radiant Energy Invisible (ultraviolet) & Visible (Light energy) 70% absorbed as thermal energy (Heat) 0.023% to photosynthesis by producers Light energy Carbon dioxide + water ---> sugar + oxygen

Sugar Contains stored energy (roots, stem, leaves, seeds) Converted to starch Some are building materials (rearrange) Carbohydrates Amino acids proteins Fats

Cellular respiration Energy released from food Takes place in the cells Consumers must eat other animals to get energy sugar + oxygen ----> carbon dioxide + water

Niche Species interactions with other species and environment What it eats, how it behaves Feeding roles Herbivore Carnivore Omnivore Scavenger

Food chains Who eats who in an ecosystem Linear representation Trophic levels 1 st trophic level Producers Make own food 2 nd trophic level primary consumers (they are herbivores) Eat producers 3 rd trophic level secondary consumers (They are carnivores or herbivores) Eat primary consumers (they eat herbivores) 4 th trophic level tertiary consumers Eat secondary consumers

Food web Who eats who in an ecosystem Represents interrelationship of different food chains Pyramids Display relationship between trophic levels on ecosystem Three types Energy Always decreases as you go up the trophic levels Number biomass