Swirling green energy factories capture the energy of sunlight, thus enabling life on earth. Cytoplasmic streaming inside plant cells is very efficient -- the slow turning of each round chloroplast means every square micron gets a chance to create energy and oxygen from sunlight. Here, we're able to see through the exceedingly thin leaf of a popular aquatic plant, Elodea, and observe microscopic cellular activities. Photosynthesis is similar in other primary producers like cyanobacteria and algae. Thanks to UCLA for the use of their beautiful microscope and motorized stage. Music by KRON.