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Class 8 Practice – Level 3 – Set 1 – Microorganisms
Total questions: 15
1.
Which of the following microorganisms is used in genetic engineering to produce insulin for diabetic patients?
Escherichia coli
Saccharomyces cerevisiae
Bacillus subtilis
Clostridium botulinum
None
2.
Which of the following microorganisms can fix nitrogen in non-leguminous plants through a free-living process?
Azotobacter
Rhizobium
Nitrosomonas
Penicillium
None
3.
Why is it more challenging to develop vaccines for viruses compared to bacteria?
Viruses can hide inside host cells.
Bacteria have fewer strains compared to viruses.
Viruses do not mutate.
Bacteria are more easily identified by the immune system.
None
4.
Which of the following is a major contributor to the rise of antibiotic-resistant bacteria?
Over-prescription of antibiotics
Use of vaccines
Use of antiseptics
High humidity
None
5.
How do microorganisms contribute to the carbon cycle?
By producing carbon dioxide during photosynthesis
By decomposing organic matter, releasing carbon dioxide
By fixing atmospheric carbon into soil
By converting carbon dioxide into oxygen
None
6.
Which of the following microorganisms is most likely to cause spoilage in canned food if proper sterilization is not maintained?
Clostridium botulinum
Rhizobium
Lactobacillus
Saccharomyces cerevisiae
None
7.
How do methanogenic microorganisms contribute to climate change?
They decompose organic waste into carbon dioxide.
They release methane, a potent greenhouse gas.
They convert carbon dioxide into methane.
They fix atmospheric nitrogen, reducing greenhouse gases.
None
8.
Which microorganism is used in the industrial production of bioethanol, a renewable fuel?
Saccharomyces cerevisiae
Bacillus thuringiensis
Nitrobacter
Aspergillus niger
None
9.
Why is tuberculosis (TB) still a global health issue despite the availability of antibiotics?
TB is caused by a virus, not bacteria.
TB bacteria have developed resistance to many antibiotics.
Vaccines for TB are ineffective.
TB spreads only through contaminated water.
None
10.
Which microorganism lives in the root nodules of leguminous plants, helping in nitrogen fixation?
Rhizobium
Azotobacter
Clostridium
Nitrobacter
None
11.
What is the role of microorganisms in bioleaching?
They convert toxic metals into non-toxic forms
They extract metals from ores by dissolving the metal content.
They break down ores into simpler chemical compounds.
They convert organic matter into usable energy.
None
12.
Which microorganism is used in the biological treatment of sewage?
Lactobacillus
Rhizobium
Pseudomonas
Methanogens
None
13.
Which microorganism has been genetically engineered to act as a biological insecticide?
Bacillus thuringiensis
Streptococcus
Clostridium
Lactobacillus
None
14.
How do preservatives like sodium benzoate inhibit the growth of microorganisms in food?
By dehydrating microorganisms
By lowering the pH, making the environment acidic
By increasing the water content of food
By providing nutrients that starve microorganisms
None
15.
Which bacterium is used to produce human growth hormone (HGH) through recombinant DNA technology?
Escherichia coli
Bacillus subtilis
Streptococcus
Lactobacillus
None
1 out of 15
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