Fine Structure of Chlorogonium elongatum with Special Reference to Vacuole Development

Abstract

The fine structure of a green alga Chlorogonium elongatum was studied.
All membranes such as the plasma membrane, mitochondrial membrane, Golgi membrane, the membrane of the endoplasmic reticulum, the vacuole membrane, the chloroplast envelope and the nuclear envelope appeared as three layers.
The thickness of these membranes was measured. The plasma membrane and the vacuole membrane were thicker than other membranes.
The origin and the development of the vacuole were concluded to be as follows: First, small vesicles were budded off from the endoplasmic reticulum and taken into the Golgi cisternae. From the opposite end of the Golgi cisternae another kind of vesicle was pinched off. Some of these vesicles grew into provacuoles and others were taken into provacuoles. Some provacuoles may be directly derived from Golgi cisternae. Provacuoles increased in size and matured into vacuole.