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.
Like the mitochondria, the chloroplast has an inner and outer membrane. Inside those membranes are its different parts, which include thylakoids and stroma. A stack of thylakoids is called a grana (pl. granum). Chlorophyll molecules on the thylakoids capture sunlight and begin the process of photosynthesis.