In a deciduous forest ecosystem, which of these organisms would be a decomposer?
a) algae
b) lichen
c) mushroom
d) oak tree

In a deciduous forest ecosystem, mushroom would be a decomposer.

A decomposer is an organism that breaks down decaying organic material. Decomposers obtain their energy by ingesting the organic material they are decomposing. Mushroom (a decomposer) is a fungus that release enzymes which decompose dead plants and animals. Mushroom can be found in a deciduous forest ecosystem (an ecosystem that contains mainly broad-leaved trees whose leaves fall during one season).

All of the electrons found in an atom balance out the protons of the atom. Protons are the positively charged particles in the atom's nucleus. The electrons are found in clouds surrounding the nucleus and they move at a very rapid pace.