Select targeted languages. 1  Catalan: fre m. 2  Chinese: Mandarin: ç¹«å¸¶ (zh), ç³»å¸¦ (zh) (jÃ¬dÃ i) 3  Finnish: frenulum. 4  Galician: freo (gl) m. 5  Greek: ÏÎ±Î»Î¹Î½ÏÏ (el) m (chalinÃ³s) 6  Icelandic: haft n. 7  Inuktitut: á¿áªááá (qillutaq)
Thylakoids float in the liquid filling the chloroplast, called the stroma. The part of the Thylakoids between two Grana is called a Lamella. Most importantly, they are the sites of the light-dependent reactions, which occur in the first step of photosynthesis.
Inside the chloroplasts are stacks of discs called thylakoids. They are compared to stacks of coins within the walls of the chloroplast, and they act to trap the energy from sunlight. The stacks of thylakoids are called grana.