LIFE SCIENCE

Detailed explanation-1: -Stroma is the fluid filling up the inner space of the chloroplasts which encircle the grana and the thylakoids. In addition to providing support to the pigment thylakoids, the stroma are now known to contain chloroplast DNA, starch and ribosomes along with enzymes needed for Calvin cycle.

Detailed explanation-2: -Within the stroma, a collection of membranous sacs are present which is called thylakoids on which the chlorophyll is found in the thylakoids and is the site for the photochemical reactions or light reactions of photosynthesis.

Detailed explanation-3: -The inner membrane surrounds a large space called the stroma, which is analogous to the mitochondrial matrix and contains many metabolic enzymes. Like the mitochondrion, the chloroplast has its own genome and genetic system. The stroma therefore also contains a special set of ribosomes, RNAs, and the chloroplast DNA.