AP BIOLOGY

Detailed explanation-1: -Definition. Grana: Grana are stacked thylakoids that are embedded in the stroma of a chloroplast. Stroma: The dark photosynthesis reaction occurs in stroma, a colourless jelly-like matrix of chloroplasts.

Detailed explanation-2: -Each granum is connected together by pieces of thylakoid membrane called lamellae. The gel-like substance which surrounds the thylakoids is called the stroma.

Detailed explanation-3: -Stroma, in botany, refers to the colorless fluid surrounding the grana within the chloroplast. Within the stroma are grana (stacks of thylakoid), and the sub-organelles or daughter cells, where photosynthesis is commenced before the chemical changes are completed in the stroma.

Detailed explanation-4: -The thylakoids consist of the photosystems that serve as the site for absorption of sunlight. The surrounding space in the stacked grana is called stroma. The stroma contains dissolved enzymes, chloroplast genome and starch granules.

Detailed explanation-5: -Stroma is the fluid-filled internal space of the chloroplasts which encircle the grana and the thylakoids. It contains chloroplast DNA, starch and ribosomes along with enzymes needed for the Calvin cycle.