____ appear as red tides in sea, by undergoing rapid multiplication.

 

State two economically important uses of:
(a) Heterotrophic bacteria
(b) Archaebacteria

What is the nature of cell-walls in diatoms?

Find out what do the terms ‘algal bloom’ and ‘red-tides’ signify.

How are viroids different from viruses?  

Describe briefly the four major groups of Protozoa.

Plants are autotrophic. Can you think of some plants that are partially heterotrophic?

What do you the terms phycobiont and mycobiont signify?  

Give a comparative account of the classes of Kingdom Fungi under the following:(i) Mode of nutrition (ii) Mode of reproduction. 

What are the characteristic features of Euglenoids?

Give a brief account of viruses with respect to their structure and nature of genetic material. Also name four common viral diseases.