Fast review mode: answers are shown by default so you can skim quickly. Hide them if you want to self-test.
In plants and algae, photosynthesis takes place in chloroplasts. A chloroplast is a type of plastid, or plant organelle. It contains the green pigment chlorophyll. The presence of chloroplasts in plant cells is one of the major ways they differ from animal cells. A chloroplast is surrounded by two membranes. Inside the membranes is a fluid-filled space called stroma. Within the stroma are structures called thylakoids. The thylakoids are stacks of flattened sacs made of membrane. The sacs contain chlorophyll. The first stage of photosynthesis takes place in the thylakoids. In the first stage, light energy is absorbed by chlorophyll and stored temporarily as chemical energy in molecules of ATP and NADPH. The second stage of photosynthesis takes place in the stroma. In the second stage, the energy in ATP and NADPH is released and used to make glucose.
Join 4M+ learners. Unlock unlimited quizzes, wrong-answer tracking, flashcards + reminders, study guides, and 1-on-1 challenges.