Amyloplast - wikipedia Amyloplast Amyloplasts in a potato cell Types of plastid Amyloplasts are non-pigmented organelles found in some plant cells. They are responsible for the synthesis and storage of starch granules, through the polymerization of glucose. Amyloplasts also convert this starch back into sugar when the plant needs energy. Large numbers of amyloplasts can be found in fruit and in underground storage tissues of some plants, such as in potato tubers. Amyloplasts are plastids, specifically leucoplasts. Plastids are a specialized class of cellular organelles that carry their own genome and are believed to be descendants of cyanobacteria ( blue - green algae ) which formed a symbiotic relationship with the eukaryotic cell. Starch synthesis and storage also takes place in chloroplasts, a type of pigmented plastid involved in photosynthesis. Amyloplasts and chloroplasts are closely related, and amyloplasts can turn into chloroplasts ; this is for instance observed when potato tubers are exposed to light and turn green. Statoliths : sensing gravity In the root cap ( a tissue at the tip of the root ) there is a special subset of cells, called statocytes. Inside the statocyte cells, some specialized amyloplasts are involved in the perception of gravity by the plant ( gravitropism ). These specialized amyloplasts -- called statoliths -- are denser than the cytoplasm and can sediment according to the gravity vector. The statoliths are enmeshed in a web of actin and it is thought that their sedimentation transmits the gravitropic signal by activating mechanosensitive channels. The gravitropic signal then leads to the reorientation of auxin efflux carriers and subsequent redistribution of auxin streams in the root cap and root as a whole. The changed relations in concentration of auxin leads to differential growth of the root tissues. Taken together, the root is then turning to follow the gravity stimuli. Statoliths are also found in the endodermic layer of the inflorescence stem. The redistribution of auxin causes the shoot to turn in a direction opposite that of the gravity stimuli. References Jump up ^ Wise, Robert ( 2007 ). `` 1 ''. The Diversity of Plastid Form and Function ( PDF ). Springer. Jump up ^ Anstis, P.J.P. ; D.H. Northcote ( 1973 ). `` Development of chloroplasts from amyloplasts in potato tuber discs ''. New Phytologist. 72 ( 3 ) : 449 -- 463. doi : 10.1111 / j. 1469 - 8137.1973. tb04394. x. Structures of the cell / organelles ( TH H1. 00.01. 2 - 3 ) Endomembrane system Cell membrane Nucleus Nucleolus Endoplasmic reticulum Golgi apparatus Parenthesome Autophagosome Vesicles Exosome Lysosome Endosome Phagosome Vacuole Acrosome Cytoplasmic granules Melanosome Microbody Glyoxysome Peroxisome Weibel -- Palade body Cytoskeleton Microfilaments Intermediate filaments Microtubules Prokaryotic cytoskeleton MTOCs Centrosome Centriole Basal body Spindle pole body Myofibril Endosymbionts Mitochondrion Plastids Chloroplast Chromoplast Gerontoplast Leucoplast Amyloplast Elaioplast Proteinoplast Tannosome Other internal RNA Ribosome Spliceosome Vault Cytoplasm Proteasome External Undulipodium Cilium Flagellum Axoneme Radial spoke Extracellular matrix Cell wall Retrieved from `` https://en.wikipedia.org/w/index.php?title=Amyloplast&oldid=807172621 '' Categories : Organelles Plant cells Plant physiology Cell anatomy Hidden categories : All articles with unsourced statements Articles with unsourced statements from October 2009 Talk About Wikipedia Беларуская Български Bosanski Català Deutsch Español Euskara فارسی Français Galego Ido Italiano Қазақша Lietuvių Nederlands 日本 語 Polski Português Русский Simple English Türkçe Українська Tiếng Việt 中文 Edit links This page was last edited on 26 October 2017, at 10 : 50. About Wikipedia

Question: what is the function of starch granules in plant cells
Answer: energy