Question

Which of the following statements is not true for nostoc?
(a)It is prokaryotic
(b)It is autotrophic
(c)It is filamentous
(d)It is macroscopic

Answer 1

Hint: It is the sort of blue-green growth with cells organized in beadlike chains that are assembled in a coagulated mass. Ranging from microscopic to walnut-sized. Reproduction is by fragmentation. A special thick-walled cell (akinete) has the power to face up to desiccation for long periods of your time.

Complete answer
Nostoc is the microscopic algae. They have filamentous and cylindrical cellular structures. They are prokaryotic cells. They do not have well-developed organelles and developed structures within the cell. They have chlorophyll pigments. These pigments allow the organism to prepare their own food. They are autotrophic in nature.

Additional information
Like most cyanobacteria, blue phycocyanin, and red phycoerythrin are the two shades of Nostoc, depending upon the chlorophyll, and can fix nitrogen in explicit cells called heterocysts. Earthly animal types have been utilized as a valuable food source in Asia.
Nostocs are photosynthesizers that use cytoplasmic photosynthetic pigments rather than chloroplasts in their metabolic process. They are single-celled, and do not have a core or other interior film frameworks; their cytoplasm is made out of 70%-85% water.
The cells don't possess flagella but are motile by a swaying motion. The division is by binary fission; some branching may occur. The cells form filamentous structures referred to as trichomes, which successively structure colonies encased by a skinny sheath; these colonies could also be mat-like or spherical and are either miniature or naturally visible - round provinces may arrive at sizes of up to 2.6 kg wet weight.

So the correct answer to the above question is ‘ It is macroscopic’.

Note: Heterocysts are generally intercalary but in the young condition, they may be terminal. Two polar knobs are available in each heterocyst, the cells of the fiber become broadened and loaded up with the food material. These thick-walled cells are called akinetes. Akinetes are generally present in chains.