Water is chemically neutral which means it is neither acidic nor basic in nature. Since acidic substance have pH less than 7.0 and basic substance have pH more than 7.0, water being neutral has exact pH of 7.0. Therefore, all cells which predominantly consists of water will have their pH value near to the pH value of water but it is not sure whether it will be slightly less or slightly more than 7.0
Natural ecosystem : ex a tropical rainforest ( basically anything made my nature ) ; artificial ecosystem : ex an aquarium, a zoo ( every type of ecosystem but man made )
