The present book entitled Cell Biology and Genetics aims to cover a wide area of cell biology and Mendelian genetics in a form especially suitable for first year undergraduates for unified syllabus of all Indian universities. The overall theme for the book is the cell as the unit of life and its components. We begin by describing the history and components of the cell as seen under the microscope. Further, we turn to the theories and plasma membrane structure and its function. The next chapter describes structure and function of cell organelles. The aim of chapter 3 to describe the biomolecules with structure of chromosomes, Watson and Crick model of DNA, differences between DNA and RNA. We have discussed cell cycle and cell division in detail in chapter 4 whereas Mendelian genetics and sex linkage with various examples given in chapter 5. The last chapter discusses various aspects of sex determination, sex differentiation, prenatal detection of genetic diseases (amniocentesis), sex linked characters, genetic diseases and abnormalities, chromosomal aberrations, eugenics and molecular evolution describes the last section. To conclude the book, summary is given at the end of each chapter for reader to review. Boxed material throughout the book is divided into examples to illustrate the topics covered in the main text, explanations of the medical relevance of the material and in depth sections that extend the coverage beyond the content of the main text.