In science, biology is the study of living organisms, which includes their structure (gross and microscopical), functioning, origin and evolution, classification, interrelationships, and distribution. [1] The subject of the study of the internal bodily thermodynamic aspects of biology is called biochemical thermodynamics. [2] In a cultural sense, there is said to exist a certain “biology of love”, that has recently been described by a unified theory of psychology and brain chemistry. [3]

References
1. Daintith, John. (2005). Oxford Dictionary of Science. New York: Oxford University Press.
2. (a) Biochemical thermodynamics – 1994 IUBMB-IUPAC Recommendations for Nomenclature.
(b) Alberty, Robert A. (2006). Biochemical Thermodynamics: Applications of Mathematica (Methods of Biochemical Analysis), Wiley-Interscience.
3. Janov, Arthur. (2000). The Biology of Love. Amherst, N.Y.: Prometheus Books.