(i) Chloroplast are the actual site of photosynthesis.
(ii) They are green plastids containing green pigment called chlorophyll.
(iii) It mainly consists of Envelope, Stroma, Thylakoids and Grana.
Envelope : Chloroplast has outer and inner envelope membranes which is seperated by intermembrane space.
Stroma : Matrix present inside to the membrane is called stroma. It contains DNA, 70 S ribosomes and other molecules required for protein synthesis.
Thylakoids : It’s membrane encloses thylakoid lumen. Thylakoids forms a stack of disc like structures called a grana (singular-granum).
Grana : Some of the thylakoids are arranged in the form of discs stacked one above the other. These stacks are termed as grana,they are interconnected to each other by membranous lamellae called Fret channels.