The term biology is derived from the Greek word βίος, bios, "life" and the suffix -λογία, -logia, "study of." It appears in German (as biologie) as early as 1791, and may be a back-formation from the older word amphibiology (meaning the study of amphibians) by deletion of the initial amphi-.Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines. Among the most important topics are five unifying principles that can be said to be the fundamental axioms of modern biology:

Biology mainly deals with the fundamental concepts of CBSE BIOLOGY i.e.  biology in class 11 CBSE biology. biology is divided in two parts CBSE class 11 biology- botany and CBSE class 11 biology- zoology similarly in class 12 CBSE Biology also divided in two papers CBSE class 12 biology botany and CBSE class 12 biology- zoology .The CBSE class 11 biology syllabus  and CBSE class 12 biology syllabus of CBSE Biology as  zoology and botany is approximately same as that of syllabus of different medical entrance examination like AIIMS, AIPMT, ZIPMET, CMC, And all other state medical entrance examination.