Autotroph: Aliving organism that makes its own complex organic matter from simple inorganic substances.
Heterotroph: a living organism that obtains its nutrients by consuming complex organic matter it cannot make its own food. All animals and fungi are heterotrophs. Most bacteria are heterotrophs.
Excretion: is the removal of the waste products of metabolism from the living organism.
Sensitivity: the ability of an organism to detect changes in its external and interna...