Part 2 — Kingdom Monera (Q26–Q50)

Part 2 — Kingdom Monera (Q26–Q50)

Q26. Which group of Monera thrives in extreme saline conditions?

• A. Thermoacidophiles

• B. Halophiles

• C. Methanogens

• D. Cyanobacteria

Answer: B

• A: Incorrect — Thermoacidophiles live in acidic hot springs.

• B: Correct — Halophiles thrive in high salt concentration.

• C: Incorrect — Methanogens produce methane in anaerobic habitats.

• D: Incorrect — Cyanobacteria are photosynthetic but not salt-loving.

Q27. Methanogens are commonly found in:

• A. Hot springs

• B. Rumen of cattle

• C. Saline lakes

• D. Human blood

Answer: B

• A: Incorrect — Thermoacidophiles are found in hot springs.

• B: Correct — Methanogens live in the rumen of cattle where they produce methane.

• C: Incorrect — Halophiles thrive in saline lakes.

• D: Incorrect — No bacteria in human blood under normal healthy conditions.

Q28. Which pigment is responsible for photosynthesis in cyanobacteria?

• A. Chlorophyll-a

• B. Phycocyanin

• C. Phycoerythrin

• D. All of these

Answer: D

• A: Partly correct — Chlorophyll-a is present.

• B: Partly correct — Phycocyanin is present.

• C: Partly correct — Phycoerythrin is present.

• D: Correct — Cyanobacteria contain all of these pigments.

Q29. Mycoplasma are unique because they:

• A. Lack cell wall

• B. Are multicellular

• C. Contain chloroplasts

• D. Have peptidoglycan wall

Answer: A

• A: Correct — Mycoplasma are wall-less bacteria.

• B: Incorrect — They are unicellular, not multicellular.

• C: Incorrect — Chloroplasts are absent.

• D: Incorrect — Peptidoglycan wall occurs in eubacteria, not Mycoplasma.

Q30. Gram-positive bacteria have:

• A. Thick peptidoglycan wall

• B. Thin wall with outer membrane

• C. No wall

• D. Protein-only cell coat

Answer: A

• A: Correct — Gram-positive bacteria stain purple due to thick peptidoglycan.

• B: Incorrect — Gram-negative bacteria have thin walls with outer membrane.

• C: Incorrect — No wall describes Mycoplasma.

• D: Incorrect — Not protein-only.

Q31. Which structure helps bacteria in conjugation?

• A. Capsule

• B. Pili

• C. Flagella

• D. Ribosomes

Answer: B

• A: Incorrect — Capsule provides protection.

• B: Correct — Pili form conjugation bridges.

• C: Incorrect — Flagella provide motility.

• D: Incorrect — Ribosomes perform protein synthesis.

Q32. Nitrogen-fixing cyanobacterium is:

• A. Oscillatoria

• B. Nostoc

• C. Anabaena

• D. Both B and C

Answer: D

• A: Incorrect — Oscillatoria does not fix nitrogen.

• B: Correct — Nostoc fixes nitrogen.

• C: Correct — Anabaena also fixes nitrogen.

• D: Correct overall since both B and C fix nitrogen.

Q33. Which feature is common to all prokaryotes?

• A. Lack of nucleus

• B. Circular DNA

• C. 70S ribosomes

• D. All of these

Answer: D

• A: True but partial.

• B: True but partial.

• C: True but partial.

• D: Correct — all these features are universal in prokaryotes.

Q34. Thermoacidophiles are adapted to:

• A. High salt

• B. High temperature and acidity

• C. Cold conditions

• D. Absence of oxygen

Answer: B

• A: Incorrect — Halophiles adapt to salt.

• B: Correct — Thermoacidophiles thrive in hot acidic springs.

• C: Incorrect — Psychrophiles survive cold, not thermoacidophiles.

• D: Incorrect — Not a defining trait.

Q35. Antibiotic resistance genes in bacteria are often carried on:

• A. Chromosomes

• B. Plasmids

• C. Ribosomes

• D. Pili

Answer: B

• A: Incorrect — Chromosomes carry essential genes, not usually resistance.

• B: Correct — Plasmids carry antibiotic resistance genes (R-plasmids).

• C: Incorrect — Ribosomes are for protein synthesis.

• D: Incorrect — Pili are for conjugation transfer, not genetic storage.

Q36. Cyanobacteria are also known as:

• A. Blue-green algae

• B. Red algae

• C. Brown algae

• D. Dinoflagellates

Answer: A

• A: Correct — Cyanobacteria are also called blue-green algae.

• B: Incorrect — Red algae are Rhodophyta (eukaryotic).

• C: Incorrect — Brown algae are Phaeophyceae (eukaryotic).

• D: Incorrect — Dinoflagellates belong to Protista.

Q37. The small circular DNA present in bacteria apart from the chromosome is called:

• A. Plasmid

• B. Episome

• C. Nucleoid

• D. Operon

Answer: A

• A: Correct — Plasmids are extra-chromosomal DNA.

• B: Incorrect — Episomes are plasmids that integrate into chromosome.

• C: Incorrect — Nucleoid is main DNA region.

• D: Incorrect — Operon is a gene cluster, not DNA element.

Q38. Which is an example of symbiotic nitrogen-fixing bacteria?

• A. Rhizobium

• B. Azotobacter

• C. Clostridium

• D. Nostoc

Answer: A

• A: Correct — Rhizobium lives in root nodules of legumes.

• B: Incorrect — Azotobacter is free-living.

• C: Incorrect — Clostridium is free-living.

• D: Incorrect — Nostoc is a cyanobacterium, not symbiotic with legumes.

Q39. Which bacterial structure provides motility?

• A. Capsule

• B. Pili

• C. Flagella

• D. Fimbriae

Answer: C

• A: Incorrect — Capsule protects.

• B: Incorrect — Pili for conjugation.

• C: Correct — Flagella enable movement.

• D: Incorrect — Fimbriae help attachment.

Q40. Endospores in bacteria function as:

• A. Reproductive structures

• B. Survival structures under harsh conditions

• C. Photosynthetic organelles

• D. Food storage

Answer: B

• A: Incorrect — Not primarily reproductive.

• B: Correct — Endospores help survival in extreme conditions.

• C: Incorrect — Not photosynthetic.

• D: Incorrect — Not for storage.

Q41. Which bacteria are used in sewage treatment?

• A. Methanogens

• B. Halophiles

• C. Cyanobacteria

• D. Streptococcus

Answer: A

• A: Correct — Methanogens produce methane in biogas plants.

• B: Incorrect — Halophiles thrive in salt.

• C: Incorrect — Cyanobacteria do photosynthesis.

• D: Incorrect — Streptococcus is pathogenic.

Q42. Which cyanobacterium is symbiotic in Cycas roots?

• A. Nostoc

• B. Anabaena

• C. Oscillatoria

• D. Spirulina

Answer: B

• A: Incorrect — Nostoc occurs in lichens.

• B: Correct — Anabaena lives in coralloid roots of Cycas.

• C: Incorrect — Oscillatoria is free-living.

• D: Incorrect — Spirulina is edible, free-living.

Q43. Bacteria reproduce mainly by:

• A. Binary fission

• B. Budding

• C. Fragmentation

• D. Sexual spores

Answer: A

• A: Correct — Binary fission is primary mode.

• B: Incorrect — Budding is rare.

• C: Incorrect — Fragmentation is rare.

• D: Incorrect — No sexual spores.

Q44. Which group of bacteria lacks peptidoglycan in cell walls?

• A. Eubacteria

• B. Archaebacteria

• C. Cyanobacteria

• D. Mycoplasma

Answer: B

• A: Incorrect — Eubacteria have peptidoglycan.

• B: Correct — Archaebacteria have unique cell wall composition.

• C: Incorrect — Cyanobacteria also have peptidoglycan.

• D: Incorrect — Mycoplasma lack walls entirely.

Q45. Spirulina is a source of:

• A. Carbohydrate

• B. Protein

• C. Lipids

• D. Nucleic acids

Answer: B

• A: Incorrect — Not carbohydrate-rich.

• B: Correct — Spirulina is rich in proteins and used as a supplement.

• C: Incorrect — Not primarily lipid-rich.

• D: Incorrect — Nucleic acids are not dietary nutrients.

Q46. Which bacteria help in production of antibiotics?

• A. Streptomyces

• B. Lactobacillus

• C. Salmonella

• D. Clostridium

Answer: A

• A: Correct — Streptomyces produces many antibiotics.

• B: Incorrect — Lactobacillus is used in curd.

• C: Incorrect — Salmonella is pathogenic.

• D: Incorrect — Clostridium causes diseases.

Q47. Cyanobacteria differ from algae in being:

• A. Eukaryotic

• B. Prokaryotic

• C. Multicellular

• D. Both A and C

Answer: B

• A: Incorrect — True algae are eukaryotic.

• B: Correct — Cyanobacteria are prokaryotic.

• C: Incorrect — Many are unicellular or colonial, not true multicellular.

• D: Incorrect — Combination is wrong.

Q48. Which bacterium is used in ethanol production?

• A. Saccharomyces

• B. Zymomonas mobilis

• C. Escherichia coli

• D. Lactobacillus

Answer: B

• A: Incorrect — Saccharomyces is a fungus (yeast).

• B: Correct — Zymomonas mobilis ferments sugars to ethanol.

• C: Incorrect — E. coli is not used industrially for ethanol.

• D: Incorrect — Lactobacillus ferments sugars to lactic acid, not ethanol.

Q49. Cyanobacteria reproduce mainly by:

• A. Conjugation

• B. Fragmentation and binary fission

• C. Sexual spores

• D. Budding

Answer: B

• A: Incorrect — Conjugation is rare in bacteria, not main method.

• B: Correct — They divide asexually by binary fission and fragmentation.

• C: Incorrect — No sexual spores.

• D: Incorrect — Budding not common.

Q50. Which bacteria convert milk into curd?

• A. Streptomyces

• B. Lactobacillus

• C. Salmonella

• D. Clostridium

Answer: B

• A: Incorrect — Antibiotic producer.

• B: Correct — Lactobacillus converts lactose into lactic acid.

• C: Incorrect — Salmonella is pathogenic.

• D: Incorrect — Clostridium causes diseases.

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