Q.Sketch and label 'Ultrastructure of Chloroplast'.

A chloroplast is a double-membrane organelle enclosing a fluid stroma containing stacks of membranous thylakoids (grana) connected by stroma lamellae, plus its own DNA, ribosomes and starch grains; labelled parts: out...

The chloroplast has an outer/inner membrane envelope, a stroma matrix, and internal thylakoid membranes organised into grana.

A chloroplast is bounded by an envelope of two membranes — a smooth outer membrane and a folded inner membrane — enclosing a proteinaceous, semi-fluid matrix called the stroma. Suspended in the stroma is an extensive internal membrane system made of flattened, disc-shaped sacs called thylakoids. Thylakoids are stacked one above another like coins to form grana (singular: granum), and adjacent grana are interconnected by thin tubular membranes called stroma lamellae (or fret channels), which help synchronise the light reactions across grana. The thylakoid membranes house chlorophyll and the photosystems where the light reactions of photosynthesis occur, while the stroma contains the enzymes of the Calvin cycle (dark reaction), along with the chloroplast's own circular DNA, 70S ribosomes, and starch grains formed as a temporary photosynthetic product. …