S. Dickinson Biology HHS Ecology S. Dickinson Biology HHS

Ecology Ecology is the scientific study of interactions among organisms and between organisms and their environment/surroundings

Interactions and Interdependence The living world is a household Biosphere is the part of the earth in which all life exists Interactions produce interdependence Interdependence contributes to change

Levels of Organization Species/Individual – can breed and produce fertile offspring (already have) Population – groups of same species in same area Community – different populations that live in an area Ecosystem – collection of organisms and their environment Biome – group of ecosystems with same climate Biosphere – earth

Look at Figure 3-2 Can a group of rabbits and a group of field mice make up the same population in an ecosystem? Why/Why not? No, because individuals that make up a __________ must be of the same ________.

Biomes Could a biome in Brazil near the equator be the same as a biome in northern Canada? Explain. No, because those two biomes would have different climates and different dominant communities

Ecological Methods Observing Experimenting Modeling Since ecological phenomena occur over long periods of time or on large spatial scale, need modeling because difficult to study

Big Idea Essential Question Matter and energy flow through living and nonliving systems Essential Question How do organisms at each trophic level get the nutrients and energy they need to function?

Energy Flow One of the most important factors that determines the system’s capacity to sustain life

Producers (already have) Sunlight is the main energy source for life on earth Some organisms rely on the energy stored in inorganic chemical compounds Mineral water

Consumers (already have) Cannot harness energy directly from the physical environment Need to eat other organisms for energy

Feeding Relationships (already have) Energy flows from sun to heterotrophs through autotrophs Food chains show one way flow of energy How energy stored by producers can be passed through an ecosystem Food webs show all feeding relationships in an ecosystem Producers make up the first trophic level Each consumer relies on the trophic level below it.

Look at Figure 3-8 How is a food web different from a food chain? A food web contains many overlapping food chains, so it is much more complex than a single food chain

Ecological Pyramids In energy pyramids, only about 10% of the energy available within one trophic level is transferred to the next trophic level The other 90% is lost as heat

Symbiosis Scenarios At the lab tables you have scenarios. It is your group’s job to sort these scenarios according to their appropriate symbiotic relationship. When you think you have it, call me over to check you. GOOD LUCK!

Cycles of Matter Matter is recycled within and between ecosystems Matter is not used up, but transformed

Recycling in the Biosphere Matter is recycled within and between ecosystems Energy flows one way Biological systems transform matter Biogeochemical cycles connect biological, geological, and chemical aspects of the biosphere

Biogeochemical Cycles Pass the same molecules around again and again within the biosphere How elements, chemical compounds, and other forms of matter are passed

Pg. 74 How can a molecule that’s swallowed by a dung beetle “combine into” – or become part of – the body tissue of a tree shrew and then an owl?

The tree shrew takes in the molecule when it eats the dung beetle, then an owl takes in the molecule when it eats the tree shrew.

Review: Water Cycle Water moves between the ocean, atmosphere, and land through transpiration, evaporation, condensation, precipitation, runoff, seepage, and root uptake Figure 3-11

Fig. 3-11 pg. 75 What are two ways that water can enter the atmosphere? Evaporation and transpiration

What process moves water from the air to the ground? Precipitation

What are two routes by which water might make its way to the ocean? Runoff and Seepage

Nutrient Cycles Every living organism needs nutrients to build tissues and carry out essential life functions Like water, nutrients are passed between organisms and the environment

Carbon Cycle Carbon is key ingredient of living tissue Carbon can take on many forms in many compounds; ex. Calcium carbonate Also a component of carbon dioxide

Four Processes that Move Carbon Through its Cycle Biological processes, ex. Photosynthesis, respiration, decomposition, take up and release carbon and oxygen Geochemical processes, ex. Erosion and volcanic activity, release carbon dioxide into the atmosphere and oceans

Mixed biogeochemical processes, ex Mixed biogeochemical processes, ex. Burial and decomposition of dead organisms and their conversion under pressure into coal and petroleum, store carbon underground Human activities, ex. Mining, cutting and burning forests, and burning fossil fuels, release carbon dioxide into the atmosphere.

Figure 3-13 Be able to “translate” diagrams pictures, labels, and arrows into complete sentences

Nitrogen Cycle Nitrogen is required to make amino acids Used to build proteins Nitrogen in many forms occurs naturally in the biosphere Nitrogen gas – 78% of earth’s atmosphere Ammonia – nitrogen containing substance Nitrate and nitrite ions – in wastes produced by many organisms and in dead and decaying organic matter

Nitrogen Fixation Bacteria convert nitrogen gas into ammonia Live in soil and on the roots of plants called legumes

Other Bacteria Bacteria in general Convert ammonia into nitrates and nitrites used by plants to make proteins Then eaten by consumers and so on Bacteria in general Some cause disease Some live inside and help with digestion Some decompose Some are producers

Denitrification Decomposers return nitrogen to soil as ammonia Some bacteria take ammonia and use it to convert nitrates into nitrogen gas

Figure 3-14 Be able to “translate” diagrams pictures, labels, and arrows into complete sentences

Nutrition Label FYI What types of information are given on the nutrition label? Serving size, total number of servings in container, specific nutrients, amount of the nutrient in one serving, percentage of daily value each amount represents What do you think a “daily value” is? How much of a nutrient a person should take in each day What does percentage of daily value mean? How much daily value is in one serving of the vitamin

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