Q. Which of the following best describes the algae known as diatoms?
- Cells have intricate shells of silicon dioxide with two halves
- Cells are encased in rigid walls composed of cellulose coated with silicon
- Cells have flagella and a light-detecting eye spot
- Cells contain carotenoid pigments as well as chlorophyll A and B
Answer: Cells have intricate shells of silicon dioxide with two halves