Biology involves the study of living organisms, from single-celled organisms to multiple-celled plants, animals and humans. Some basic biology class topics might include cellular structure and functions, evolution and natural selection, heredity and genetics and ecosystems. The study of this life science changes and evolves as ongoing research reveals new discoveries about how living organisms work and interact, down to the smallest possible detail. Since the subject is much too broad to cover in only one class, many high schools also offer advanced biology classes as well as more specialized courses such as anatomy.
Biology, study of living things and their vital processes. The field deals with all the physicochemical aspects of life. The modern tendency toward cross-disciplinary research and the unification of scientific knowledge and investigation from different fields has resulted in significant overlap of the field of biology with other scientific disciplines. Modern principles of other fields—chemistry, medicine, and physics, for example—are integrated with those of biology in areas such as biochemistry, biomedicine, and biophysics.
Biology is subdivided into separate branches for convenience of study, though all the subdivisions are interrelated by basic principles. Thus, while it is custom to separate the study of plants (botany) from that of animals (zoology), and the study of the structure of organisms (morphology) from that of function (physiology), all living things share in common certain biological phenomena—for example, various means of reproduction, cell division, and the transmission of genetic material.
Biology is often approached on the basis of levels that deal with fundamental units of life. At the level of molecular biology, for example, life is regarded as a manifestation of chemical and energy transformations that occur among the many chemical constituents that compose an organism. As a result of the development of increasingly powerful and precise laboratory instruments and techniques, it is possible to understand and define with high precision and accuracy not only the ultimate physiochemical organization (ultrastructure) of the molecules in living matter but also the way living matter reproduces at the molecular level. Especially crucial to those advances was the rise of genomics in the late 20th and early 21st centuries.