As a science, Biology is a subject devoted to the study of living organisms. It also includes, virology – the study of viruses. Biology as a subject is extremely fascinating and in the 21st Century it is one of the most rapidly developing sciences, especially in the fields of genomics, proteomics and personalized medicine. Because it is such a broad subject it has many sub-disciplines, which some people find more interesting than others. For examples, some students are excited by biochemistry and molecular biology, while others prefer the physiological approach, evolutionary science or ecology. In A level Biology most of these disciplines are touched upon. Having some biological literacy is now quite important as so many issues in the media and commerce have a biological basis, such as stem cell technology or new developments in molecular biology or medicine.

Biology is important if a student wants to study a medically-related discipline or Life Sciences. Biology is generally required for medicine, dentistry, veterinary science, and pharmacy. Biology is important for all Life Sciences, including Biochemistry, Immunology, Microbiology, Informatics and Genomics, Physiology and Agricultural Science. Many careers have biology as their core discipline. Careers such as professional ecologists, biochemists, forensic science, the pharmaceutical industry and many more, all need an in-depth knowledge of key areas of biology.