Ecology Van Au 12-1 Melissa Lee 12-2 Victoria Robinson 12-3 Jonathan Tieu 12-4

Ecology is… the study of the relations of organisms and their interaction with their environment or physical surroundings.

Levels of Organization Population- a group of interacting organisms of the same species and area Species- groups of organisms that resemble one another in appearance, behavior, chemistry, and genetic makeup Organism- any form of life

Levels of Organization cont’d Biosphere- the sum of all organisms and their environments Ecosystem- a biological community of organisms interacting with their environment Communities- a group of different species and populations inhabiting a specific area

Biosphere (4 layers)

Lithosphere (land) Crust and upper mantle Fossil fuels, minerals, nutrients

Hydrosphere (H2O) Solid Liquid Gas Ice, permafrost Liquid water Water vapor

Atmosphere (air) Troposphere Stratosphere 78% nitrogen, 21% oxygen Ozone Absorbs UV rays

Energy Flow Energy flow in an ecosystem: Energy is lost in food chains and webs the 2nd law of thermodynamics there is a decrease in the amount of energy available to each succeeding organization in a food chain or web.

“…”vores Herbivores- organisms that mainly eat plants Carnivores- organisms that mainly eat meat Omnivores- organisms that primarily eat both plants and meat Detritivores- organisms that get their nutrients from dead animals and plants and their waste

Can you guess which organism belongs to each category? Which is the: Herbivore? Carnivore? Omnivore? Detritivore?

Trophic Levels Producers/Autotrophs make their food from inorganic compounds using photosynthesis or chemosynthesis. Consumers/Heterotrophs get their nutrients from eating other organisms. Primary consumers eat producers. Secondary and tertiary consumers eat other consumers. Decomposers eat decaying plant and animal matter as well as waste.

Food Webs Trophic levels are interconnected. Within a more connected food web.

Water, Carbon, and Nitrogen Cycles Three of the most important cycles we learned about this semester were: The Water Cycle The Carbon Cycle The Nitrogen Cycle

Can you guess the steps of the water cycle, APES kids?

The Water Cycle Condensation- the change from water vapor to liquid Precipitation rain, sleet, snow, hail Infiltration The movement of water through soil. Runoff is the flow of water over land into bodies of water Evaporation- when water changes phases, from liquid to gas/vapor. Transpiration- the process in which water vapor is given off by plants The answer.

6CO2 + 6H2O (+ light energy) C6H12O6 + 6O2 The Carbon Cycle The process by which carbon is absorbed through photosynthesis and released back into the air by cellular respiration. 6CO2 + 6H2O (+ light energy) C6H12O6 + 6O2

The Nitrogen Cycle Cycle in which nitrogen converts to its various chemical forms. The nitrogen cycle consists of several major steps: nitrogen fixation, nitrification, ammonification, and denitrification.

The Nitrogen Cycle cont’d Nitrogen fixation- bacteria in soil and aquatic environments convert gaseous nitrogen to ammonia, then is converted to ammonium ions to be used by plants. Nitrification- two step process in which bacteria in soil convert NH3 and NH4+ first to nitrite ions and secondly to nitrate ions, which are absorbed by the roots of plants. Ammonification, decomposer bacteria convert organic material into simpler nitrogen-containing inorganic compounds such as ammonia and water soluble salts containing ammonium salts. Denitrification- nitrogen removed from the soil by chemical reduction.

That’s All, Study Hard!