Los leucoplastos son plastidios que almacenan sustancias incoloras o poco coloreadas. Abundan en órganos de almacenamientos limitados por membrana que se encuentran solamente en las células de las plantas y de las algas. Están rodeados por dos membranas, al igual que las mitocondrias, y tienen un sistema de membranas internas que pueden estar intrincadamente plegadas. Los plástidos maduros son de tres tipos: leucoplastos, cromoplastos y cloroplastos. Los leucoplastos almacenan almidón o, en algunas ocasiones, proteínas o aceites. Los cromoplastos contienen pigmentos y están asociados con los colores naranja y amarillo brillante de frutas, flores y hojas del otoño. Los cloroplastos son los plástidos que contienen clorofila y en los cuales tiene lugar la fotosíntesis. Al igual que otros plástidos, están rodeados por dos membranas; la membrana interna, la tercera membrana de los cloroplastos, forma una serie complicada de compartimientos y superficies de trabajo internos. En resumen, son organelos rodeados de dos membranas y se clasifican según los pigmentos y sustancias que contengan: \n* Leucoplastos: sin pigmentos. \n* Cloroplastos: con clorofila. \n* Cromoplastos: contienen pigmentos, como los carotenos. \n* Amiloplastos: contienen almidón.

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Leucoplasts (λευκός leukós „white“, πλαστός plastós „formed, molded“ ) are a category of plastid and as such are organelles found in plant cells. They are non-pigmented, in contrast to other plastids such as the chloroplast. Lacking photosynthetic pigments, leucoplasts are not green and are located in non-photosynthetic tissues of plants, such as roots, bulbs and seeds. They may be specialized for bulk storage of starch, lipid or protein and are then known as amyloplasts, elaioplasts, or proteinoplasts (also called aleuroplasts) respectively. However, in many cell types, leucoplasts do not have a major storage function and are present to provide a wide range of essential biosynthetic functions, including the synthesis of fatty acids such as palmitic acid, many amino acids, and tetrapyrrole compounds such as heme. In general, leucoplasts are much smaller than chloroplasts and have a variable morphology, often described as amoeboid. Extensive networks of stromules interconnecting leucoplasts have been observed in epidermal cells of roots, hypocotyls, and petals, and in callus and suspension culture cells of tobacco. In some cell types at certain stages of development, leucoplasts are clustered around the nucleus with stromules extending to the cell periphery, as observed for proplastids in the root meristem. Etioplasts, which are pre-granal, immature chloroplasts but can also be chloroplasts that have been deprived of light, lack active pigment and can be considered leucoplasts. After several minutes exposure to light, etioplasts begin to transform into functioning chloroplasts and cease being leucoplasts.Amyloplasts are of large size and store starch.Proteinoplasts store proteins and are found in seeds (pulses).Elaioplasts store fats and oils and are found in seeds. They are also called oleosomes. [castor, groundnut]Etioplasts are plastids without pigments and store food and lamellar structures. These plastids occur in etiolated plants due to the absence of light.

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