The purpose of chloroplasts in plant cells is to facilitate photosynthesis, the process by which plants convert light energy into chemical energy stored as glucose. Chloroplasts contain the green pigment chlorophyll, which absorbs sunlight and enables the conversion of carbon dioxide and water into glucose and oxygen. Beyond energy production, chloroplasts also play a role in synthesizing essential molecules and maintaining plant health. They are crucial for the growth and survival of plants and contribute significantly to the ecosystem by providing oxygen and food.