What is the nature of cell-walls in diatoms?
The cell walls of diatoms contain silica and are indestructible. The cell wall is made up of two thin overlapping walls which fit together such as a soap box. When the diatoms die, the silica in their cell walls gets deposited in the form of diatomaceous earth.
Discuss how classification systems have undergone several changes over a period of time?
State two economically important uses of:
(a) Heterotrophic bacteria
(b) Archaebacteria
Find out what do the terms ‘algal bloom’ and ‘red-tides’ signify.
How are viroids different from viruses?
