Question

Explain the ultrastructure of chloroplast ?

Answer 1

Chloroplast is a double membrane organelle. It may vary in shape and size in various organisms .Example, cup shaped in Chamydomonas, star shaped in Zygnema, Sipiral in Spirogyra. However in most of the organisms it is lens shaped. The membranes are differentiated as inner and outer. The space between the two membranes is called the inter membrane space. The inner membrane encloses semi fluid stroma, and bears ETS for ATP synthesis. Embedded within the stroma are sac like structures called thylakoids that are stacked to form the granum (plural grana). Light harvesting pigments are present on the thylakoid membrane. Grana are connected to each other by grana lamellae or stoma lamellae.