Electron Microscope Observations on the Root Hair Cell of <i>Azolla imbricata</i> Nakai

Abstract

1. In the electron micrographs of root hair cells of Azolla imbricata, the following intracellular organellae were observed.2. In the vacuoles, a number of heavily electron-dense bodies are seen. They appear to be aggregates of particles of ca. 30mμ in diameter and probably of lipid nature.3. The mitochondria show features of the typical structure of those described in plant cells.4. The plastids in cells treated with osmium fixatives appear to be composed of lamellae and grana-like structures. The plastids in cells fixed with permanganate show the piles of several short lamellar structures, i.e., grana-like structures, but show no so-called lamellar structures.5. The endoplasmic reticulum is seen irregularly winding in a shape of discrete layers or in stacks of lamellar layers. Palade granule-like bodies are seen in osmium-fixed cells, but not demonstrated in permanganate-fixed cells.6. The Golgi-like structures are composed of cisternae, and small discrete vesicles are often found at the edges of the cisternae, which appear more clearly in permanganate-fixed cells than in osmium-fixed ones.