There are many lines of evidence that mitochondria and plastids including chloroplasts arose from bacteria. In plants and algae, photosynthesis takes place in organelles called chloroplasts. Manganese is also important in photosynthetic oxygen evolution in chloroplasts in plants. The cytoplasmic layer is home to several organelles, like the chloroplasts and mitochondria. Green algae are examples of algae that have primary chloroplasts derived from endosymbiotic cyanobacteria. All chloroplasts and some mitochrondria, both organelles derived from endosymbiosis of bacteria, also use FtsZ. Such structures appear in the outer membranes of gram-negative bacteria, chloroplasts, and mitochondria. Thylakoids are membrane-bound compartments inside chloroplasts and cyanobacteria. Leaves are normally green, due to chlorophyll in chloroplasts in the mesophyll cells. The chloroplastida chloroplasts, or green chloroplasts, are another large, highly diverse primary chloroplast lineage. Group 1 chaperonins are commonly found in bacteria, chloroplasts, and mitochondria. Mesophyll chloroplasts have a little more peripheral reticulum than bundle sheath chloroplasts. Protein synthesis within chloroplasts relies on two RNA polymerases. Most dinophyte chloroplasts are secondary red algal derived chloroplasts. Manganese is necessary for photosynthesis, including the building of chloroplasts.