AP BIOLOGY

Detailed explanation-1: -A cell is the smallest unit of a living thing. A living thing, whether made of one cell (like bacteria) or many cells (like a human), is called an organism. Thus, cells are the basic building blocks of all organisms.

Detailed explanation-2: -A cell is the smallest and most basic form of life. Robert Hooke, one of the first scientists to use a light microscope, discovered the cell in 1665. In all life forms, including bacteria, plants, animals, and humans, the cell was defined as the most basic structural and functional unit.

Detailed explanation-3: -Cells are considered the basic units of life in part because they come in discrete and easily recognizable packages. That’s because all cells are surrounded by a structure called the cell membrane-which, much like the walls of a house, serves as a clear boundary between the cell’s internal and external environments.

Detailed explanation-4: -In biology, the smallest unit that can live on its own and that makes up all living organisms and the tissues of the body. A cell has three main parts: the cell membrane, the nucleus, and the cytoplasm.

Detailed explanation-5: -A cell is the smallest unit that is typically considered alive and is a fundamental unit of life. All living organisms are composed of cells, from just one (unicellular) to many trillions (multicellular). Cell biology is the study of cells, their physiology, structure, and life cycle.