Q. Consider the following statements I. Agar, one of the commercial products obtained from $Gelidium$ and $Gracilaria$ are used to grow microbes and in preparations of ice-creams and jellies II. $Chlorella\$and $Spirogyra$ are used in sewage disposal ponds III. Some species of marine algae like $Porphyra,\ Laminaria\$and $Sargassum$ are used as food Which of the statements given above are correct?
A) I and II
B) I and III
C) II and III
D) I, II and III
Explanation
Agar is obtained from Gelidium, Gracilaria, Chondrus, Ceramium, etc., and used in microbiological works to solidify culture media. Green unicellular algae such as Chlorella and Chlamydomonas are used in sewage disposal ponds. They remove $CO_{2}$ and restore $O_{2}$ by the process of photosynthesis and make the sewage water enhitable for many fishes and aerobic bacteria. Porphyra Laminaria and Sargassum are used as food
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.