Site of photosynthesis

Photosynthesis takes place in all green parts of the plants. In higher plants chloroplast is the cell organelle, containing chlorophyll. In prokaryotic primitive plants, chlorophyll is found in the photosynthetic membranes suspended in the cytoplasm.
The green color of the chloroplast is because of the chlorophyll, a chief pigment involved in the photosynthesis. In plants, leave are the part, where most of the chloroplasts are located. Sometime stems also contain chloroplast and appear green.

Chloroplast

Structure of chloroplast

Chloroplasts are double membrane-bound cell organelle. Inside there are numerous filamentous and discoid membranous compartments of various size. The filamentous compartment is known as lamella or thylakoid, while the discoid compartments which are stacked one over other are called as grana. Thus, there are compartment; one inside the thylakoids or grana is known as lumen and other outer to thylakoids or grana and inner to the outer double membrane is known as stroma.
Various components of light reaction including chlorophyll are located in the membrane of thylakoids and grana, where as, the component of dark reaction including various enzymes are localized in the stroma. Beside these, the stroma of chloroplast contains, starch, oil droplets, DNA, RNA and ribosomes. It is because of the presence of own DNA, RNA and ribosomes chloroplasts can synthesize some proteins of their own need. Hence, chloroplast is a semi-autonomous organelle.