Question

The maximum biomass of living diatoms is to be found in
A.Marine pelagic habitats
B.Moist soil and swamp
C.Deep coast mines
D.Salt lakes

Answer 1

Hint: Diatoms are microscopic , unicellular, photosynthetic organisms of various colours and diverse forms. They may be circular, rectangular, triangular, elongated, spindle shaped, half moon shaped or filamentous.

Complete answer:
-Diatoms is the collective name of about 170 genera and 5500 species of golden brown photosynthetic protists.
-Most of the diatoms occur as phytoplanktons both in fresh and marine waters. A few forms occur as benthos at the bottom of water reservoirs. Some are terrestrial and grow on moist soil.
-Diatoms constitute a major part of phytoplanktons of the oceans.
-It is estimated that about 60 ton blue whales may have approximately 2 tons of plankton in its gut.

So, the correct answer is option A . Marine pelagic habitats
Additional information:
The siliceous cell walls of diatoms are indestructible ( i.e. do not decay easily ). They were collected over millions of years on the sea floors, called diatomite or diatomaceous earth. These deposits may extend for several hundred meters in certain areas.Diatoms constitute an important producer in the form of phytoplanktons in the aquatic ecosystem. They are the main source of food to aquatic animals.Large fossil sedimentary deposits of diatomite or diatomaceous earth are mined and used in various industries.The earth is very soft, light, fire proof and is inert chemically.It is mainly used in industrial filtrations, particularly in the filtration of sugars, oils, alcohols and antibiotics.Diatomite is used as a cleaning agent in toothpaste and metal polishes, added to paints for enhancing night visibility, added to make sound proof rooms, used as insulating material in refrigerators and furnaces and employed as a source of water glass or sodium silicate.

Note:
Examples of diatoms are Navicula, Cyclotella, Pinnularia, Diploneis, Coscinodiscus, Triceratium etc. Diatoms are a member of kingdom protista.