Ribosomes are organelles composed of two subunits of ribosomal RNA (rRNA) and proteins. They are found in the rough endoplasmic reticulum in the case of eukaryotic cells and are responsible for protein synthesis by helping to translate messenger RNA information into amino acids. In prokaryotic cells, they are mainly found in the cytoplasm.
The mitochondria is the "energy factory of the cell". It has an internal matrix where the Krebs cycle occurs and an internal membrane where the electron transport chain is located. The Krebs cycle produces energy from pyruvate from glycolysis and the electron transport chain produces energy from the electrons obtained in glycolysis and the Krebs cycle.