what do chloroplasts do

Chloroplasts are organelles found in plant cells that are responsible for photosynthesis, the process by which light energy is converted into chemical energy. Chloroplasts have a highly permeable outer membrane, a less permeable inner membrane, and a narrow intermembrane space in between. They contain pigments such as chlorophyll a and chlorophyll b, which absorb light energy for photosynthesis. Chloroplasts also produce energy through photosynthesis and oxygen-release processes, which sustain plant growth and crop yield. In addition to photosynthesis, chloroplasts perform many biosyntheses such as the production of amino acids, phytohormones, nucleotides, vitamins, lipids, and secondary metabolites. Chloroplasts are highly sensitive organelles that can sense changes in the environment, such as shifts in light intensity and temperature, and play a crucial role in relaying signals involved in a plants defenses against pathogens and other stressors. Chloroplasts also communicate with the nucleus through plastid-to-nucleus retrograde signaling to acclimate to environmental stresses.