Answer:
True
Step-by-step explanation:
Diatoms are unicellular (one celled) algae. They undergo photosynthesis to produce their own food. They are found in many different marine and aquatic environments and ecosystems.
Diatoms do not move. They don’t have cilia or flagellum, which would allow them to move around and swim.
Therefore, it is true that diatoms lack a flagellum.