What are cells? Explain.

the smallest unit that can live on its own and that makes up all living organisms and the tissues of the body.  

Explanation:

Cells are the building block or the basic structures of all living organisms.Cells are the smallest units of living things, they are thr basic units of organization of all organisms.All cells are derived from other cells (pre-existing cells) by means of divisions.Cells contain a blueprint (i.e. information) outlining their growth, development and function.Within cells, there are sites and structures where the chemical reactions of life occur (metabolism) .

The right answer is Chloroplast.

The chloroplast is a specific organelle of plant cells, probably derived from an endosymbiosis event of a cyanobacterium by a primitive eukaryotic cell. The chloroplast is indeed separated from the cytoplasm by a double membrane, two membranes separated by an intermembrane space.

Inside, the chloroplast consists of a stack of thylacoids, which bathe in the stroma (intrachloroplastic fluid).