Modern cell biology is a dynamic discipline that combines the interests and techniques of many scientific fields, including molecular biology, genetics, developmental biology and biochemistry. Cell biologists investigate the basic structural and functional units of life: the cells that compose all living organisms. They aim to understand cellular structure; composition and regulation; the organelles that cells contain; cell growth; nuclear and cellular division; and cell death. Understanding how cells work is fundamental to many areas of biology and is of particular importance to biomedical fields such as cancer research and the development of diseases.