With reference to Spirulina, consider the following statements:
- (1) It is rich in protein.
- (2) It is a prokaryote.
- (3) It has heterocysts.
Which of the statements given above is/are correct?
- AOnly (1)
- BAll three
- C(1) and (2)
- DNone of the above
Show answer and explanation
Correct answer: (c) (1) and (2)
Explanation
Spirulina is a cyanobacterium (blue-green alga) eaten as a food supplement.
- (1) Correct: it is very rich in protein, about 60–70% of its dry weight, with vitamins and minerals.
- (2) Correct: as a cyanobacterium, it is a prokaryote: it has no nucleus or membrane-bound organelles.
- (3) Wrong: Spirulina has no heterocysts, the special cells in which cyanobacteria such as *Nostoc* and *Anabaena* fix nitrogen.
So only (1) and (2) are correct.