Amyloplast

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Amyloplasts in a potato cell

Amyloplasts ( old Gr . Ἄμυλον ámylon “flour”, “ starch ” and πλαστός plastós “shaped”) are organelles that occur in some plant cells. They are a chlorophyll- free form of plastids and therefore belong to the leucoplasts . Their function is to create and store strength. They are therefore found in the storage organs of plants, i.e. in fruits, parts of the stem axis or in underground reserve organs (storage roots, tubers , rhizomes ).

The strength can be demonstrated under the microscope through the blue-violet color reaction that results with the iodine-containing Lugol's solution . The amyloplasts in potatoes usually contain one grain of starch (sometimes two), the growth rings of which are visible under a microscope (especially in polarized light). In the banana , the amyloplasts form elongated structures through unilateral growth, which are best seen in semi-ripe bananas.

In spurge is found Amyloplasts dumbbell or bone-shaped, while in the fruits of oats , rice and bluegrass from many part of composite grains Amyloplasts are included.

Amyloplasts can also play a role in gravitropism , the vertical growth.

Amyloplasts can develop from chloroplasts via the intermediate form chloroamyloplast .

Individual evidence

  1. ^ J. Stanga, A. Strohm, PH Masson: Studying starch content and sedimentation of amyloplast statoliths in Arabidopsis roots. In: Methods in molecular biology (Clifton, NJ). Volume 774, 2011, pp. 103-111, ISSN  1940-6029 . doi : 10.1007 / 978-1-61779-234-2_7 . PMID 21822835 .
  2. A. Stensballe, S. Hald, G. Bauw, A. Blennow, KG Welinder: The amyloplast proteome of potato tuber. In: The FEBS journal. Volume 275, Number 8, April 2008, pp. 1723-1741, ISSN  1742-464X . doi : 10.1111 / j.1742-4658.2008.06332.x . PMID 18331355 .
  3. SC Rastogi: Cell And Molecular Biology . New Age International, 2006, ISBN 81-224-1487-7 , pp. 224 ( limited preview in Google Book search).