Biological Classification And System Of Classification Question 70
Question: Which of the following is not a blue-green algae
[CPMT 2004]
Options:
A) Nostoc
B) Anabaena
C) Lichen
D) Aulosiras
Show Answer
Answer:
Correct Answer: C
Solution:
Blue-green algae (cyanobacteria) are photosynthetic, filamentous prokaryotes.
The cells are without membrane bound cell organelles like chloroplast, mitochondria etc. Nostoc is free-living nitrogen-fixing cyanobacteria having cells arranged in beadlike chains (trichomes) that are grouped together in a gelatinous mass (Nostoc balls).
They fix atmospheric nitrogen in specialized cells called heterocysts. Anabaena is a genus of cyanobacteria with beadlike or barrel-like cells and interspersed enlarged spores (heterocysts).
Aulosira is a genus of cyanobacteria which forms colonies composed of filaments of moniliform cells. Whereas lichens are formed by the close association of 2 different partners, one is an algal component (phycobiont) and other is a fungal component (mycobiont).
BETA
