Prokaryotic cells are the earliest cells to evolve and lack membrane-bound organelles. They have genetic material located in the cytoplasm and ribosomes as their only organelle. Bacterial cells have a cell wall, plasma membrane, cytoplasm containing ribosomes and nucleoid, and sometimes a mesosome. Eukaryotic cells evolved later and have a membrane-bound nucleus and organelles. They include membrane-bound structures like the endoplasmic reticulum, Golgi apparatus, mitochondria, lysosomes, and a cytoskeleton. Plant cells also have a cell wall, chloroplasts, and a large central vacuole.