The Ultrastructure of the Chloroplast in Spinacia oleracea

Abstract

The ultrastructure of the chloroplasts in the leaves of Spinacia oleracea was examined.
Three different appearances of the structure of the chloroplast were observed. In the first appearance, the grana seemed to be formed by sacs, the membranes of which were about 35Å thick. In the second appearance, the grana seemed to be formed by sacs, the membranes of which were very thin and hardly detectable. On the outside of the membrane small particles were observed. In the third appearance, the grana seemed to be formed by sacs with double membrane. The figures with the second appearance were assumed to be more significant than those with the other two appearances.