Question

Protist used for the construction of sound proof rooms is

• A. Dinoflagellate
• B. Diatoms
• C. Euglenoids
• D. Zooflagellates

Answer 1

The correct option is B Diatoms

Cell of Diatoms are surrounded by cell wall having two parts or frustules; frustules make two overlapping halves (the epitheca and the hypotheca). Presence of numerous tiny pores in frustules connects the protoplast of the cell with the outside environment. The pectin substance of cell wall is richly impregnated with silica, which creates patterns of minute perforations and striations. Around 90 percent of diatomaceous cell wall is silica. Shells of diatoms are highly resistant to decomposition due to presence of silica and are deposited in ocean beds leading to formation of porous diatomaceous earth. It serves as porous acoustic material i.e. a solid material with cavities/channels to facilitate the entry of sound waves and their absorption with very little reflection. This makes option B correct. Dinoflagellates have armoured cellulosic cell wall while euglenoids lack cell wall but have pellicle which is a semi-rigid proteinaceous structure. Zooflagellates are protozoans that lack cell wall. This makes options A, C and D incorrect. Correct answer is B.