Energy


 * __Energy Transfer & The Ten Percent Rule__**

The Sun provides energy to the Earth. Every day, the Sun supplies energy in the form of light rays. However, a large percentage of this incoming energy is not usable due to reflection by the atmosphere, clouds, and oceans. The remaining rays will reach the Earth. The sunlight on the Earth’s biosphere is used by the organisms. Plants utilize this energy to facilitate photosynthesis, and animals indirectly make use of the Sun’s energy through consumption of the plants.

Energy transfer is not very efficient in the system as a significant amount is not used productively. Much of this energy has been changed to heat energy, where it heats up the surfaces of the biosphere. In addition, energy is required to facilitate respiration, digestion, and heat in organisms. Essentially, only about 10% of the consumed energy is utilized productively and available for transfer to the next trophic level. The fact that only 10% is efficiently utilized by organisms is known as the Ten Percent Rule.

It is also important to acknowledge the Conservation of Energy. Energy can neither be created nor destroyed, but only be changed in form. In terms of energy transfer, all energy taken into the system must equal all energy given out.

__**Food Webs**__

Food Webs are intended to show energy transfer from one organism to another through consumption. The food web is a reprsentation of the different consumption interactions between the different organisms in an ecosystem. Food webs are a good way to get a picture of the feeding interactions of an ecosystem

The food web is made up of various chains. Each chain is made up of one consumption interaction between organsims. The food web represents different levels of consumers and producers. The producers' energy comes from the sun, the primary consumers' energy comes from consuming the producer, the secondary consumers get their energy from the primary cosumers, etc. The top of the food chain is called the appex consumer. The decomposers go on the side of the web. Arrows are drawn from the source of the energy to the organism getting the energy.