Microbes in Human Welfare
Test 2

Correct answer Carries: 4.

Wrong Answer Carries: -1.

Which microbe is responsible for nitrogen fixation in root nodules of leguminous plants?

Azotobacter
Rhizobium
Lactobacillus
Bacillus
2

Rhizobium forms a symbiotic relationship with leguminous plants and fixes atmospheric nitrogen.

Which fungus produces cyclosporin A, an immunosuppressive drug?

Trichoderma polysporum
Penicillium notatum
Aspergillus niger
Rhizopus stolonifer
1

Trichoderma polysporum produces cyclosporin A, which is used to suppress immune responses in organ transplant patients.

Which of the following microbes is used as a biocontrol agent against insect pests?

Bacillus thuringiensis
Escherichia coli
Clostridium tetani
Lactobacillus acidophilus
1

Bacillus thuringiensis (Bt) produces toxins that kill insect larvae.

Which of the following statements about microbes in food production is correct?

Lactobacillus is used in the curdling of milk.
Saccharomyces cerevisiae is used in antibiotic production.
Microbes are never used in food preservation.
Penicillium helps in making ethanol.
1

Lactobacillus converts lactose into lactic acid, which helps in the curdling of milk.

Which of the following statements regarding Bacillus thuringiensis (Bt) is incorrect?

Bt toxin is used as a biopesticide.
Bt produces an inactive toxin that becomes active in insect guts.
Bt is used in genetically modified crops for pest control.
Bt toxin affects human cells like pesticides do.
4

Bacillus thuringiensis toxin is highly specific to insect larvae and does not affect humans.

Which of the following statements about bioactive molecules is correct?

Cyclosporin A is an antibiotic.
Statins are used to lower cholesterol.
Streptokinase is an enzyme that digests proteins.
Penicillin is an enzyme.
2

Statins, produced by Monascus purpureus, are used to lower cholesterol levels in the blood.

Which of the following statements regarding sewage treatment is incorrect?

Secondary treatment involves microbial degradation of organic matter.
Methanogens play a role in biogas production.
Sludge digestion is carried out by aerobic bacteria.
Primary treatment removes physical impurities.
3

Sludge digestion is carried out by anaerobic bacteria, not aerobic bacteria.

Which type of bacteria helps in the biological treatment of sewage?

Methanogens
Aerobic heterotrophic bacteria
Cyanobacteria
Sulfur bacteria
2

Aerobic heterotrophic bacteria break down organic matter in sewage treatment plants.

Which microorganism is used in the production of Roquefort cheese?

Lactobacillus
Propionibacterium shermanii
Penicillium roqueforti
Saccharomyces cerevisiae
3

Penicillium roqueforti is a fungus used to ripen Roquefort cheese, giving it a distinctive flavor.

Which microorganism is used in the commercial production of citric acid?

Acetobacter aceti
Aspergillus niger
Clostridium butylicum
Lactobacillus
2

Aspergillus niger is a fungus used for large-scale citric acid production.

Performance Summary

Score:

Category Details
Total Attempts:
Total Skipped:
Total Wrong Answers:
Total Correct Answers:
Time Taken:
Average Time Taken per Question:
Accuracy:
0