Cells are the building blocks of living things. They are derived from other cells by division and they are the site of all the chemical reactions of life (metabolism). A cell is the smallest unit of all the unit of organisation we can say alive .
Cells are extremely small . They are measured in units of a thousandths of a millimetre and they must be viewed by microscopy.
The cells of plants and animals have common features, including a nucleus,cytoplasm and cell membrane. The distinctive features of plant cells are a cellulose cell wall, the presence of large permanent vacuoles and the possible presence of chloroplasts,the site of photosynthesis .