A cell is the basic unit of living organisms (both plants and animals)
that is capable of reproducing itself exactly. That is, there are
components within cells (organelles), but they do not reproduce themselves
independently of the cell(s) of which they are a part.
Nuclear pores permit substances (such as nutrients, waste, and
cellular information) to pass both into, and out of, the nucleus.
See the Revision page about Cell
Structure for further information including a diagram of the
structure of a basic cell including nuclear pores, organelles, etc..