Diatomaceous earth is used as a heat insulator in boilers and steam pipes because the cell wall of diatom is
1. Composed of iron
2. Composed of silicon dioxide
3. a good conductor of heat
4. a bad conductor of electricity
Select the wrong statement:
1. | The walls of diatoms are easily destructible |
2. | Diatomaceous earth is formed by the cell walls of diatoms |
3. | Diatoms are chief producers in the oceans |
4. | Diatoms are microscopic and float passively in water |
In which group of organisms the Cell walls form two thin overlapping shells which fit together?
1. | Chrysophytes | 2. | Euglenoids |
3. | Dinoflagellates | 4. | Slime moulds |