Life
Life is a characteristic that distinguishes physical entities that do have biological processes, such as signaling and self-sustaining processes, from those that do not, either because such functions have ceased, or because they never had such functions and are classified as inanimate. Various forms of life exist, such as plants, animals, fungi, protists, archaea, and bacteria. The criteria can at times be ambiguous and may or may not define viruses, viroids, or potential synthetic life as "living". Biology is the science concerned with the study of life.
Science
The objective world of science has nothing in common with the world of things-in-themselves of the metaphysician. The metaphysical world, assuming that it has any meaning at all, is irrelevant to science.
A. D'Abro, The Evolution of Scientific Thought from Newton to Einstein (1927) footnote, p. 152.