Inside has thylakoid membranes; flattened stack of them is granum (linked by intergranal lamellae), stroma is a colorless fluid-filled matrix containing many different soluble enzymes, starch grains, DNA loops, and many 70s ribosomes
Biconvex discs, 2-10 µm long, surrounded by double membrane called 'chloroplast envelope'; outer membrane is more permeable due to more transport proteins
Grana and stroma can be seen under a high-power light microscope; thylakoids are visible with an electron microscope, starch granules (sometimes very large) and lipid droplets (products of photosynthesis) are stored in chloroplast
