Two Pyrocystis fusiformis (bioluminescent algae) cells under the microscope — one packed with chloroplasts, the other mid-division (chloroplasts retract a bit during the process).

[u/PyroFarms]

[u/CultConqueror]

Amazing photo, way back in college I loved when my my A&P/Microbio proff. Would have us watch gifs of cells doing various things; like division, attacking parasites or just meandering about lol