An abscessed tooth is an infection within a tooth that has spread to the root tip or around the root. This infection originates from the tooth's inner chamber, which is called the pulp chamber.. Contained within the pulp chamber are blood vessels and nerves, collectively called the pulp..
Earthworms prefer to eat at night, though, rather than in the day. That is why they are also called nightcrawlers. Besides adding nutrients to the soil, earthworms keep the soil healthy by tunneling. Worms do not have claws or paws to make tunnels, but they do have mouths. As they eat (and eat and eat), they create tunnels that keep the soil open and full of paths for water and air.
Lichens Contribute to Soil Formation. Lichens thrive in undisturbed sites where nothing else will grow. They grow on rocks, barren soil and the bark of dead or live trees. Lichens are not parasitic when they grow on trees, they just use the tree bark as a home. They enrich the soil by trapping water, dust and silt. When lichens die they contribute organic matter to the soil, improving the soil so that other plants can grow there. Lichens Fix Nitrogen