This book is organized in such a way as to meet both the challenging teaching work of teachers and the students' effort to successfully meet the multiple requirements of Biology in the science direction.

In all chapters it includes:
- alphabetical and thematic classification of terms in each chapter.
- understandable presentation and organization of theory with diagrams.
- comparative tables of basic Biology terms.
- summary of basic knowledge at the end of each chapter.
- methodology for solving all exercises and exemplary solutions.
- exemplary answers to all theory questions.
- exercises for solving and questions.

For further understanding of the theory, the book includes:
- 41 diagrams,
- 45 tables,
- 75 images.