Living things are made from materials which are taken from the world around us (we're actually all made from star dust).
Plants take in nutrients for the soil they grow in and the air that surrounds them. The elements are all important. They are as follows:
These elements plants take in have to be returned to the earth otherwise we would eventually run out and all die. The way thesis done is through process called decay. Decay happens on all living organisms which can provide a food source for microorganisms.
Decay varies depending of three factors:
- Amount of oxygen (microorganism work better in aerobic conditions).
- Moisture (the wetter the land, the better microorganisms can cause decay).
- Warmth (Microorganisms love to be warm - that's why to stop food from rotting, we freeze it or keep it cold).
What Is Decay?
Decay is a process cause by microorganism (most of the time). Decay involves microorganisms growing on dead plants/animals and digesting them. Microorganisms when they digest break down the complex compounds and leave them on their basic element form. An example this is protein. Protein is a very complicated compound, but when microorganism break it down, they break the bonds and release it back into the ground as the elements that make the protein and not the actual protein.
This is important due to the fact if this process didn't happen. Plants and animals would constantly be used and nevertheless returning, slowly depleting the planet away until there was no nutrients left to support life.
Decay also happens through excretion. When a animal eats a plant, the nutrients it can digest are ridden of from the body through excretion. Eventually microorganisms build up on the fesses and break it down, releasing the simple elements (which where too complicate for the animal to digest) back into the earth.