Question

Which of the following can be used as bacteriological filter

• A. Gelidium
• B. Batrachospermum
• C. Oscillatoria
• D. Cosmarium

Answer 1

The correct option is D Cosmarium

• Cosmarium is a genus of freshwater organisms belonging to the Charophyta, a division of green algae from which the land plants emerged.
• The bacteriological filter is a filter whose pores are fine enough to filter the bacteria and Cosmarium is a bacteriological filter because its cell membrane is highly porous that can filter the organism as small as bacteria.
  
• Hence Cosmarium can be used as a bacteriological filter.
• So, the correct answer is 'Cosmarium'.