This second edition of this book is extensively revised.It now covers the complete syllabus prescribed by the Medical Council of India for the MBBS course. Although it is designed as a basic text book for the undergraduate student,it has resource material for postgraduates and advanced learners in biochemistry and medicine. The topics are developed in a manner that encourages the student to develop analytical ability as opposed to memory-based learning. Each chapter begins with At a glance which gives a bird’s eye view of the content, thus facilitating better comprehension of the whole. At the end of each chapter, MCQs, Clinical case studies, Problem based exercises and Riddles have been given. These will be of immense help to the students preparing for various competitive examinations in India and abroad that include USMLE, PLAB, and All India MD/MS entrance examinations.