Biology Welcome to the fascinating study of life in its varied forms and colours. The diversity of life is expressed and seen through beautiful orchids, butterflies, colourful fish and cool penguins. Biology is the scientific study of life that enables us to understand how the great diversity of life on earth evolved from the first microbe. Biology helps us to understand how a single cell, which is the fundamental unit of life develops into a complex plant or animal. A closer look at the sun flower reveals the highly ordered structure that characterises life. Sunflowers grow well in full sun by converting solar energy into chemical energy of food and in the bud stage exhibit heliotropism by tracking the sun from east to west, while at night they return to an eastward orientation. This motion is performed by motor cells in the pulvinus, a flexible segment of the stem just below the bud. Biology is a multi disciplinary science as the organisms and the world they live in are natural systems to which basic concepts of chemistry and physics apply. Important themes that encompass study of life includes cell, heritable information in the form of DNA, bilogical systems, evolution, energy processing, regulation and interaction with the environment. Biology is the foundation for medical research which improved quality of life with new medical therapies. Let us explore this exciting study of 'Life' to know more about ourselves and the world around us.