biology : class12 Cyanobacterial Sources : Definition, Sources, Nutritional Importance : Single Cell Protein MCQ Questions and Answers
Practice important
Cyanobacterial Sources
MCQ questions and answers.
Page 1
of
1
|
10
MCQ Questions
1. Which cyanobacterium is most prominently associated with commercial single-cell protein production because of its high protein content and ease of cultivation in alkaline water?
A.
Arthrospira platensis
B.
Anabaena azollae
C.
Nostoc commune
D.
Oscillatoria limosa
Correct Answer:
Arthrospira platensis
Explanation:
Arthrospira platensis, commonly marketed as Spirulina, is a major cyanobacterial source of single-cell protein because it grows rapidly in alkaline media and produces biomass containing a high proportion of protein.
2. The organism commonly called Spirulina and used as a cyanobacterial single-cell protein source is taxonomically placed in which genus?
A.
Nostoc
B.
Arthrospira
C.
Anabaena
D.
Chlorella
Correct Answer:
Arthrospira
Explanation:
Commercial Spirulina belongs mainly to the genus Arthrospira, especially Arthrospira platensis and Arthrospira maxima. Chlorella is a green alga rather than a cyanobacterium.
3. Which combination contains only cyanobacterial genera that have been considered potential sources of single-cell protein?
A.
Arthrospira, Nostoc, Anabaena
B.
Chlorella, Scenedesmus, Arthrospira
C.
Saccharomyces, Arthrospira, Nostoc
D.
Spirulina, Candida, Chlorella
Correct Answer:
Arthrospira, Nostoc, Anabaena
Explanation:
Arthrospira, Nostoc, and Anabaena are cyanobacterial genera. Chlorella and Scenedesmus are green microalgae, while Saccharomyces and Candida are yeasts.
4. Why is Arthrospira considered a particularly suitable cyanobacterial source for single-cell protein compared with many other microbial sources?
A.
It requires organic substrates as its exclusive carbon source
B.
It forms protein-rich biomass while growing photosynthetically in alkaline conditions
C.
It lacks pigments and therefore cannot perform photosynthesis
D.
It produces biomass only after forming a fungal mycelium
Correct Answer:
It forms protein-rich biomass while growing photosynthetically in alkaline conditions
Explanation:
Arthrospira can use light and carbon dioxide for photosynthetic growth and tolerates alkaline culture conditions. Its resulting biomass is protein-rich, making it valuable as cyanobacterial single-cell protein.
5. A culture intended to produce cyanobacterial single-cell protein is maintained at high pH to favor a Spirulina-like organism and reduce contamination. Which organism is the intended source?
A.
Arthrospira maxima
B.
Rhizopus stolonifer
C.
Candida utilis
D.
Chlorella vulgaris
Correct Answer:
Arthrospira maxima
Explanation:
Arthrospira maxima is a Spirulina-type cyanobacterium that grows well in alkaline media. The other listed organisms are fungi, yeast, or green microalgae rather than the intended cyanobacterial source.
6. Which feature most directly distinguishes nitrogen-fixing cyanobacterial sources such as Nostoc from Arthrospira as potential single-cell protein organisms?
A.
Presence of heterocysts specialized for nitrogen fixation
B.
Absence of chlorophyll-containing photosynthetic membranes
C.
Dependence on animal-derived amino acids for growth
D.
Formation of a true multicellular fungal thallus
Correct Answer:
Presence of heterocysts specialized for nitrogen fixation
Explanation:
Nostoc and related cyanobacteria may contain heterocysts, specialized cells that fix atmospheric nitrogen. This trait can support growth in nitrogen-limited environments, although Arthrospira is the more established commercial cyanobacterial protein source.
7. Which pairing correctly matches a cyanobacterial source with its common food or single-cell protein name?
A.
Arthrospira platensis — Spirulina
B.
Chlorella vulgaris — Nostoc
C.
Candida utilis — Anabaena
D.
Saccharomyces cerevisiae — Arthrospira
Correct Answer:
Arthrospira platensis — Spirulina
Explanation:
Arthrospira platensis is widely known commercially as Spirulina and is used as a protein-rich cyanobacterial biomass. The other pairings incorrectly assign cyanobacterial names to yeasts or green algae.
8. Which cyanobacterial characteristic supports the use of Arthrospira biomass as a nutritional supplement rather than merely as a biological fertilizer?
A.
Its harvested dry biomass contains substantial protein and several micronutrients
B.
It produces cellulose fibers as its principal edible component
C.
It derives all biomass from decomposition of animal tissues
D.
It contains no photosynthetic pigments or nitrogenous compounds
Correct Answer:
Its harvested dry biomass contains substantial protein and several micronutrients
Explanation:
Arthrospira biomass is valued nutritionally because it contains a high proportion of protein along with pigments, vitamins, minerals, and other nutrients. This composition supports its role as cyanobacterial single-cell protein.
9. A researcher selects a cyanobacterium that can be cultivated in open ponds, harvested as filamentous biomass, and processed into a protein-rich supplement. Which source best fits this description?
A.
Arthrospira platensis
B.
Escherichia coli
C.
Penicillium chrysogenum
D.
Saccharomyces cerevisiae
Correct Answer:
Arthrospira platensis
Explanation:
Arthrospira platensis forms filamentous biomass and is extensively cultivated in ponds for production of Spirulina-based protein supplements. The other organisms are bacterium, filamentous fungus, and yeast, respectively.
10. Which statement most accurately compares Arthrospira with Nostoc as cyanobacterial sources of single-cell protein?
A.
Arthrospira is widely commercialized for protein-rich biomass, whereas Nostoc is recognized mainly as a potential cyanobacterial source
B.
Nostoc is a yeast, whereas Arthrospira is a green alga
C.
Both are non-photosynthetic fungi cultivated only on animal waste
D.
Arthrospira lacks protein, whereas Nostoc is used exclusively for lipid production
Correct Answer:
Arthrospira is widely commercialized for protein-rich biomass, whereas Nostoc is recognized mainly as a potential cyanobacterial source
Explanation:
Arthrospira has an established history as a commercial cyanobacterial protein source. Nostoc species can also provide nutrient-rich biomass and have nitrogen-fixing abilities, but they are less prominent commercially as single-cell protein products.
Short Questions and Answers
Practice short questions and answers related to
Cyanobacterial Sources
.
Short questions are currently unavailable for this page.