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This section includes 20 Mcqs, each offering curated multiple-choice questions to sharpen your Microbiology knowledge and support exam preparation. Choose a topic below to get started.
1. |
Which among the following develop in the upper portion of the Winogradsky column? |
A. | Sulfate-reducing bacteria |
B. | Green-sulfur bacteria |
C. | Purple-sulfur bacteria |
D. | Thiobacilli |
Answer» E. | |
2. |
The reduction of sulphates and sulphites to hydrogen sulphide is done by which group of bacteria? |
A. | aerobic sulfate-reducing bacteria |
B. | photosynthetic sulphur bacteria |
C. | anaerobic sulphate-reducing bacteria |
D. | heterotrophic bacteria |
Answer» D. heterotrophic bacteria | |
3. |
The Winogradsky column experiment is done in the dark. |
A. | True |
B. | False |
Answer» C. | |
4. |
Sulphates are reduced to hydrogen sulphide by _____________________ |
A. | Desulfotomaculum sp. |
B. | Thiobacillus thiooxidans |
C. | Photosynthetic sulfur bacteria |
D. | Rhodospirillum |
Answer» B. Thiobacillus thiooxidans | |
5. |
Cysteine breaks down in presence of cysteine desulfurase to give _________________ |
A. | oxaloacetic acid |
B. | sulphuric acid |
C. | pyruvic acid |
D. | glyoxalate |
Answer» D. glyoxalate | |
6. |
Which among the following are the most important agents for carbon dioxide fixation? |
A. | bacteria |
B. | fungi |
C. | algae |
D. | protozoa |
Answer» D. protozoa | |
7. |
SULPHATES_ARE_REDUCED_TO_HYDROGEN_SULPHIDE_BY______________________?$ |
A. | Desulfotomaculum sp. |
B. | Thiobacillus thiooxidans |
C. | Photosynthetic sulfur bacteria |
D. | Rhodospirillum |
Answer» B. Thiobacillus thiooxidans | |
8. |
The reduction of sulphates and sulphites to hydrogen sulphide is done by which group of bacteria?$ |
A. | aerobic sulfate-reducing bacteria |
B. | photosynthetic sulphur bacteria |
C. | anaerobic sulphate-reducing bacteria |
D. | heterotrophic bacteria |
Answer» D. heterotrophic bacteria | |
9. |
The_Winogradsky_column_experiment_is_done_in_the_dark.$ |
A. | True |
B. | False |
Answer» C. | |
10. |
Which among the following is a non-sulfur purple bacteria? |
A. | Rhodomicrobium |
B. | Thiobacillus |
C. | Chromatium |
D. | Chlorobium |
Answer» B. Thiobacillus | |
11. |
Purple and green sulfur bacteria use ___________________ as the electron donor to reduce carbon dioxide. |
A. | S<sup>2-</sup> |
B. | SO4<sup>2-</sup> |
C. | H<sup>2</sup>S |
D. | Organic acids |
Answer» D. Organic acids | |
12. |
Which among the following develop in the upper portion of the Winogradsky column? |
A. | Sulfate-reducing bacteria |
B. | Green-sulfur bacteria |
C. | Purple-sulfur bacteria |
D. | Thiobacilli |
Answer» E. | |
13. |
Which of the following processes is performed by Thiobacillus thiooxidans? |
A. | converting sulphur to sulphates |
B. | converting sulphur to sulphides |
C. | converting sulphur to sulphites |
D. | converting organic sulphur to inorganic sulphur |
Answer» B. converting sulphur to sulphides | |
14. |
Cysteine breaks down in presence of cysteine desulfurase to give _________________ |
A. | oxaloacetic acid |
B. | sulphuric acid |
C. | pyruvic acid |
D. | glyoxalate |
Answer» D. glyoxalate | |
15. |
Cellobiose is metabolized directly by many microorganisms. |
A. | True |
B. | False |
Answer» C. | |
16. |
In carbon cycle flow of energy is _________________ |
A. | bidirectional |
B. | linear |
C. | cyclic |
D. | irreversible |
Answer» C. cyclic | |
17. |
The amount of organic material in the forest soil remains approximately the same from year to year. |
A. | True |
B. | False |
Answer» B. False | |
18. |
Cellulose is degraded to cellobiose by the enzyme __________________ |
A. | cellulase |
B. | beta-glucosidase |
C. | hexokinase |
D. | cellulose dehydrogenase |
Answer» B. beta-glucosidase | |
19. |
Fresh air contains approximately ______ percent carbon dioxide by volume. |
A. | 0.01 |
B. | 2 |
C. | 5 |
D. | 0.03 |
Answer» E. | |
20. |
Which among the following are the most important agents for carbon dioxide fixation? |
A. | bacteria |
B. | fungi |
C. | algae |
D. | protozoa |
Answer» D. protozoa | |