Lustre and metallic are finishes of photo prints that are very different from each other. While preserving memories, people like to order their prints in either Lustre or metallic finishes depending upon their liking.
Structure of an animal cell. The cell (from Latin cella, meaning small room) is the basic structural, functional, and biological unit of all known living organisms. A cell is the smallest unit of life that can replicate independently, and cells are often called the building blocks of life. The study of cells is called cell biology.
Quick Answer. Cells are considered the smallest unit of life because they are the smallest components in living things, and some organisms, such as bacteria, are made up of single cells. In addition, each part of the animal body, including blood vessels, organs and skin, is made up of a congregation of cells.