GENERAL HISTOLOGY

Detailed explanation-1: -In plants and algae, which developed much later, photosynthesis occurs in a specialized intracellular organelle-the chloroplast. Chloroplasts perform photosynthesis during the daylight hours. The immediate products of photosynthesis, NADPH and ATP, are used by the photosynthetic cells to produce many organic molecules.

Detailed explanation-2: -Within chloroplasts, chlorophyll is the pigment that absorbs sunlight. It is stored in the thylakoid membranes in protein complexes called photosystem I and photosystem II. The series of light-dependent reactions begins when sunlight hits a molecule of chlorophyll, located in photosystem II.

Detailed explanation-3: -The Structure and Function of Chloroplasts Plant chloroplasts are large organelles (5 to 10 m long) that, like mitochondria, are bounded by a double membrane called the chloroplast envelope (Figure 10.13).

Detailed explanation-4: -Chloroplasts are present in the cells of all green tissues of plants and algae. Chloroplasts are also found in photosynthetic tissues that do not appear green, such as the brown blades of giant kelp or the red leaves of certain plants.