Energy Flow and chemical Cycling
If you look at the nature of an ecosystem, you will see that every ecosystem is characterized by two fundamental phenomena: energy flow and chemical cycling. This module will take a closer look at energy flow. Energy flow begins when producers absorb solar energy. Through photosynthesis, producers make organic nutrients (glucose) directly for themselves and indirectly for the other populations of the ecosystem. As the energy is transferred from producers to consumers, a small amount of energy is lost to the environment as heat. Therefore, there must be a continual supply of solar energy to fuel the ecosystem.
Only a portion of the organic nutrients made by producers is passed on to consumers because plants use organic molecules to fuel their own cellular respiration. Similarly, only a small percentage of nutrients consumed by lower level consumers such as herbivores is available to higher level consumers, or carnivores. Of the assimilated energy, a large portion is used during cellular respiration for the production of ATP and thereafter becomes heat. Only the remaining energy, which is converted into increased body weight or additional offspring becomes available to carnivores.
Only a portion of the organic nutrients made by producers is passed on to consumers because plants use organic molecules to fuel their own cellular respiration. Similarly, only a small percentage of nutrients consumed by lower level consumers such as herbivores is available to higher level consumers, or carnivores. Of the assimilated energy, a large portion is used during cellular respiration for the production of ATP and thereafter becomes heat. Only the remaining energy, which is converted into increased body weight or additional offspring becomes available to carnivores.
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