1. Some Introductory Notes to Cell Behavior

The cell is the most basic functional, structural and biological unit of life as we understand it. Cells are able to perform coherent functions and make up all tissues and organs of all living multicellular organisms; in consequence, there are usually referred to as life’s building blocks. They can replicate independently and contain the hereditary information necessary for regulating cell functions, including growth, metabolism, apoptosis, protein synthesis, movement and replication, for transmitting information to the next generation of cells. As present handbook will focus on the development strategies for biomedical microsystems aimed at interacting with human cells, which constitute our tissues and organs and play a fundamental role in health and disease, it is important to provide a brief introduction to the cell as complex multi-scale and multi-physical/chemical living organism, to its structure and subunits and to its main functions, before focusing on the field of biomedical microsystems. In addition, as tissue repair and tissue engineering are directly connected to stem cells and several chapters of present Handbook will cover development strategies for biodevices linked to tissue engineering, which constitute a very relevant part of the biomedical microsystems designed for interacting at a cellular level, it is very important to provide an introductory note to cell types and to cell differentiation processes. This chapter pretends to serve as introduction to the handbook, as regards the nature, structure and main types and functions of cells.