This provides a brief overview of the cell:
Prokaryotic vs Eukaryotic
Bacterial cell wall, structure and function overview of
Ultrastructure and Function of the: Nucleus and Nucleolus, Chromatin and Matrix, Smooth and Rough ER, Ribosomes, Golgi Complexes
Ultrastructure and Function: Lysosomes, Perioxisomes, Glycogen, Lipid, Cytoplasmic Filaments, Centrasome and Centrioles.
source