Within a cell there are different organelles, the above are as such.
The nucleus, often thought as as the centre of a cell, contains all the genetic
information of a cell (the cells chromosomes), it controls the activities of the cell.
Cytoplasm surrounds the nucleus within the cell walls. It is where reactions take place in the cell.
The cell membrane controls the movement of chemicals in and out of the cell.
The cell wall, which is made up of cellulose, strengthens the cell.
Chloroplast contain chlorophyll, and are used in photosynthesis.
Vacuole keeps the cell turgid (basically keeps the cell filled with water.)