Thylakoid
The thylakoid is a membrane bound compartment inside chloroplasts and cyanobacteria. They are the sight of the light-dependent reactions of photosynthesis.
Granum
Chloroplast thylakoids frequently form stacks referred to as grana. Grana are connected by intergranal or stroma thylakoids, which join granum stacks together as a single functional compartment.
Stroma
The stroma is the coulourless fluid surrounding the grana within the chloroplast.
Inner & Outer Bilayer Membrane
Each of the envelope bilayers cocsists of lipids and is approximately 6 - 8 nm thick. The outer layer is found to be permeable to most ions and metabolites while the inner layer is very specialized containing transport proteins controlling transport in and out of the organelle.
Chloroplasts cannot be made by the plant cell, and must be inherited by each daughter cell during cell division.