Q40. A chronic infection is caused by a eukaryote with a chitinous cell wall that produces spores. Which organism is implicated?
[RRB Group D | 2026 | PYQ (2025 recruitment cycle)]
- Fungus
- Alga
- Bacterium
- Protozoan
Answer: (A) Fungus
Explanation: Fungi possess a true nucleus and cell walls containing chitin. Many reproduce by spores and some cause persistent infections in humans. Bacteria lack a true nucleus; protozoa usually lack a rigid chitin wall, making fungus the appropriate identification.
Q39. A fungal culture grows best in a warm, moist incubator. Which biological process is most directly favoured?
[RRB Group D | 2026 | PYQ (2025 recruitment cycle)]
- Spore germination and fungal growth
- Production of chlorophyll
- Formation of red blood cells
- Photosynthesis
Answer: (A) Spore germination and fungal growth
Explanation: Warmth and adequate moisture promote the germination of many fungal spores and the extension of hyphae. Humid skin folds similarly favour superficial fungal infections. Temperature requirements differ between species, and excessive heat can inhibit growth or kill fungi.
Q38. Rice blast is classified as which type of plant disease?
[CGPSC Prelims | 2025 | PYQ]
- Fungal
- Bacterial
- Nutritional deficiency
- Viral
Answer: (A) Fungal
Explanation: Rice blast is primarily caused by Magnaporthe oryzae, also called Pyricularia oryzae in its asexual form. The fungus infects leaves, nodes and panicles, producing characteristic lesions. Resistant varieties and appropriate disease management reduce crop damage.
Q37. Why do fungal spores help fungi survive and disperse under unfavourable conditions?
[MP Police Constable | 2025 | PYQ]
- They always contain chlorophyll
- They must fertilise an egg
- They are relatively resistant and easily dispersed
- They are always large and immobile
Answer: (C) They are relatively resistant and easily dispersed
Explanation: Fungal spores often have protective walls and can remain viable during unfavourable conditions. Their small size assists transport by air or contact. When moisture, nutrients and temperature become suitable, surviving spores germinate and establish new colonies.
Q36. Which fungal pathogen has been reported to develop resistance to azole antifungals through chromosomal changes?
[RRB Group D | 2025 | PYQ]
- Candida albicans
- Candida tropicalis
- Aspergillus niger
- Rhizopus stolonifer
Answer: (B) Candida tropicalis
Explanation: Candida tropicalis can acquire resistance-associated chromosomal alterations, including copy-number changes, alongside other mechanisms. Azole drugs such as fluconazole inhibit fungal ergosterol synthesis. Antifungal resistance requires laboratory surveillance because different Candida species may respond differently to treatment.
Q35. Which is NOT a principal criterion traditionally used to classify fungi into major groups?
[NEET | 2024 | PYQ]
- Morphology of mycelium
- Mode of nutrition
- Mode of spore formation
- Nature of fruiting body
Answer: (B) Mode of nutrition
Explanation: Traditional fungal classification considers the structure of mycelium, production of spores and fruiting bodies. Mode of nutrition is not the chief basis for these classes because many fungi share absorptive heterotrophy while differing substantially in reproduction.
Q34. Claviceps fusiformis causes which disease of pearl millet (bajra)?
[CCI Junior Assistant | 2024 | PYQ]
- Ergot
- Smut
- Rice blast
- Bacterial blight
Answer: (A) Ergot
Explanation: Claviceps fusiformis infects flowers of pearl millet and causes ergot disease. A sticky honeydew stage may be followed by dark fungal sclerotia replacing grains. Contaminated produce may contain toxic ergot alkaloids harmful to animals and humans.
Q33. Which plant-pathogenic fungus associated with silver-leaf disease has also been reported in a rare human infection?
[TNPSC Group 4 | 2024 | PYQ]
- Plasmodiophora brassicae
- Chondrostereum purpureum
- Puccinia graminis
- Taphrina deformans
Answer: (B) Chondrostereum purpureum
Explanation: Chondrostereum purpureum is best known as the cause of silver-leaf disease in certain trees. A rare human infection was reported, illustrating that fungal host ranges can occasionally surprise researchers. Such cases do not imply routine person-to-person transmission.
Q32. Which of these diseases is caused by a fungus?
[SSC CHSL Tier I | 2023 | PYQ (2022 recruitment cycle)]
- COVID-19
- Ringworm
- Tuberculosis
- Cholera
Answer: (B) Ringworm
Explanation: Ringworm, or dermatophytosis, is caused by dermatophyte fungi rather than worms. It commonly presents as an itchy, scaly patch. COVID-19 is viral, while tuberculosis and cholera are bacterial, making ringworm the only fungal option.
Q31. Assertion: Ringworm is a fungal disease.
Reason: It can be caused by Trichophyton and Microsporum.
Choose the correct response.
[MP Police Constable | 2023 | PYQ]
- Both assertion and reason are correct
- Only assertion is correct
- Only reason is correct
- Both are incorrect
Answer: (A) Both assertion and reason are correct
Explanation: The assertion and reason are both correct. Trichophyton and Microsporum are important dermatophyte genera causing infections of keratin-rich tissues. Epidermophyton is another recognized genus. These infections are termed tinea or dermatophytosis according to the affected body site.