- All life depends on the solar energy absorbed during photosythesis, it is stored in plant chemicals such as starch.
- Autotrophs create their own food and energy.
- Hetrotrophs is an organism that must eat other organisms for food and energy.
- Chlorophyll in plant cells absorbs light for the process of photosynthesis. The word equation is;
Carbon Dioxide + Water ---------> Glucose + Oxygen
- Glucose is used for different things, making cellulose, proteins, starch and chlorophyll.
- Nitrates are absorbed from the soil and added to glucose to form proteins.
- They are absorbed by the roots by 'active transport'.
- Starch has little effect on the osmotic balance of the cell, so it is used for energy storage.
- Photosynthesis can be affected by low temperatures, low carbon dioxide or different lights levels.
- Human activity is incresing atmoshperic carbon dioxide levels.
- Compenstaion points points occur when respiration makes as much carbon dioxide as phosynthesis uses.
- Energy is transferred when living things are eaten or broken down by decomposers.
- Pyramids of biomass show the food available to the herbivores and carnivores in an ecosystem.
- Only about 10% of the energy in biomass is passed on at each stage in the food chain. The rest is lost to decomposers or waste heat.
- Soil contains living organisms, decaying material, sand, clay, air, water and dissolved minerals.
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