糊粉粒

糊粉粒

糊粉粒 植物細胞內儲藏蛋白質的結構,具有消化的作用。每個糊粉粒是一個液泡,其中儲藏的蛋白質。無定形的蛋白質常被一層膜包裹成圓球形顆粒(結晶的蛋白質因具有晶體和膠體的二重性,因此被稱為擬晶體,蛋白質擬晶體有不同的形狀,但常呈方形。),它是穩定的、無生命的、化學作用不活潑的蛋白質。糊粉粒主要存在於植物的種子內,特別是含有脂肪的種子,如箆麻等。在種子萌發時,這類蛋白質又被植物利用。禾本科植物種子的糊粉粒集中在胚乳的外層細胞中,形成糊粉層。

鑑別

(1)加碘-碘化鉀試液,顯淺黃色或黃色。

(2)加硝酸汞試液,顯磚紅色。材料中如含有多量脂肪油,宜先用乙醚或石油醚脫脂後進行試驗。

概述

非活性而又較穩定的結晶體或無定形的小顆粒,貯存在植物細胞質中.這種蛋白質與構成原生質的活性蛋白質不同,不能吸水膨脹,故又稱蛋白質晶體.主要存在於植物的種子中,特別是含有脂肪的種子中.如在蓖麻和油桐的胚乳細胞中,就含有較大的糊粉粒,在顯微鏡下,可見到一個到多個圓球形的晶體或多角形的蛋白質結晶體.在豌豆的子葉細胞和馬鈴薯塊莖細胞中,都可見到蛋白質結晶.而在大豆種子中則常可見到糊粉粒與澱粉粒混存在一起的現象.此外,在玉

糊粉粒糊粉粒
米、小麥、水稻等禾本科植物種子裡,糊粉粒分布在胚乳的最外一層細胞中,特稱為“糊粉層”,常因精碾而損失.Non-active but more stable crystalline or amorphous small particles, stored in the plant cytoplasm. That the activity of proteins and constitute the protoplasm of different proteins, not swell, and therefore also known as protein crystals. Mainly in plant seeds, especially those containing fat seeds. like the endosperm in the castor and tung tree cells, it contains a large aleurone grains under the microscope, can be seen one to many spherical or polygonal crystals of protein crystals. In the pea cotyledon cells and potato tuber cells, protein crystallization can be seen. while in soybean seeds can frequently be seen in the aleurone grains and starch grains mixed with the existence of the phenomenon. In addition, corn, wheat, rice and other grasses seeds, the aleurone grains distributed in the outermost layer of endosperm cells, special called "aleurone", often lost due to fine grinding.

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