Cells are the building blocks of organic evolution. It is a fascinating reality that cells form muscle tissue, organs and bones in living organisms and have the unique ability to regenerate. The human body is made up of an average of 37 trillion cells though its function is controlled by a simple genetic code and it can destroyed by a harmful DNA called a virus. Biology has an extensive scope which makes it an exciting subject to study. Biology is a dynamic course whereby learners are alerted to new and fascinating discoveries as scientific research progresses.