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Any of several cytoplasmic organelles, such as chloroplasts, that contain genetic material, have a double membrane, and are often pigmented. Plastids are found in plants, algae, and certain other eukaryotic organisms and have various physiological functions, such as the synthesis and storage of food.
[From Greek plastis, plastid-, feminine of plastēs, molder, from plastos, molded; see plastic.]
plas·tid′i·al (plăs-tĭd′ē-əl) adj.
(Botany) any of various small particles in the cytoplasm of the cells of plants and some animals that contain pigments, starch, oil, protein, etc. See chromoplast
[C19: via German from Greek plastēs sculptor, from plassein to form]
a small, double-membraned organelle of plant cells and certain protists, occurring in several varieties, as the chloroplast, and containing ribosomes, prokaryotic DNA, and, often, pigment.
[1875–80; < German Plastide < Greek plastid-, s. of plástis, feminine derivative of plástēs modeler, creator, derivative of plássein to form]
A structure found in plant cells, green algae, and certain protozoans. Some plastids, such as the chloroplasts in plant leaves, contain pigments.
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|Noun||1.||plastid - any of various small particles in the cytoplasm of the cells of plants and some animals containing pigments or starch or oil or protein|
granule - a tiny grain
chromoplast - plastid containing pigments other than chlorophyll usually yellow or orange carotenoids
chloroplast - plastid containing chlorophyll and other pigments; in plants that carry out photosynthesis