NEET Biology Biological Classification MCQs Set 25

Answer: (a) lichen

Explanation:
1. Lichens are the symbiotic association between algae and fungi.
2. Fungi provides the raw material and algae manufacture the food.
3. Hence option (a) is correct: lichen

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (c) bacteriophage

Explanation:
1. The virus which attacks bacteria is called bacteriophage, e.g.
2. T II phage, M13, 174 I etc.
3. Hence option (c) is correct: bacteriophage

Teacher's Note:
1. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (a) bacterium

Explanation:
1. Citrus canker is caused by bacterium, Xanthomonas citri.
2. Bacterium is rod shaped, motile, flagellate and gram negative.
3. Hence option (a) is correct: bacterium

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (a) Nostoc

Explanation:
1. Nostoc is a cyanobacterium.
2. Cyanobacteria are gram (–) ve prokaryotes which perform oxygenic photosynthesis like plants.
3. Hence option (a) is correct: Nostoc

Teacher's Note:
1. Cyanobacteria can be unicellular (e.g.
2. Spirulina), colonial. (e.g.

Answer: (d) either DNA or RNA

Explanation:
1. A virus has only one kind of nucleic acid in its core, either DNA or RNA, never both.
2. The nucleic acid is covered by a protein coat (capsid).
3. Hence option (d) is correct: either DNA or RNA

Teacher's Note:
1. Virus are obligate intracellular parasite which can reproduce only by invading and taking over other cells as they lack the cellular machinery for self reproduction.
2. Virus has either DNA or RNA and never both.

Answer: (c) Oscillatoria

Explanation:
1. Hormogonia is a part of a filament of a cyanobacterium that detaches and grows by cell division into a new filament.
2. Cyanobacteria mostly multiply by asexual means like binary fission, small fragments (hormogones), hormospores, akinetes, endospores etc.
3. Hence option (c) is correct: Oscillatoria

Teacher's Note:
1. Common cyanobacteria are-Nostoc, Anabaena, Oscillatoria etc.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (a) Yeast

Explanation:
1. Yeast is the only member in kingdom fungi which is unicellular.
2. Nostoc : Blue green algae E. coli : Bacterium Albugo : Parasitic fungi.
3. Hence option (a) is correct: Yeast

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (d) murein

Explanation:
1. Bacterial cell wall consists of peptidoglycan/murein/mucopeptide which contains polymers of modified sugars (N-acetyl glucosamine and N- acetylmuramic acid) cross linked by short peptides.
2. Hence option (d) is correct: murein

Teacher's Note:
1. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (a) Amoeba

Explanation:
1. Cell wall is a characteristic of bacteria, plants and fungi.
2. Hence option (a) is correct: Amoeba

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (c) Yeast

Explanation:
1. Heterotrophs were the first to be evolved and fungi in the plant kingdom are heterotrophs.
2. Yeast with its characteristic absence of chlorophyll and its vegetative propagation through budding and saprophytic nature shows it is a fungus.
3. Hence option (c) is correct: Yeast

Teacher's Note:
1. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (b) ascomycetes

Explanation:
1. Powdery mildews are caused by fungi belonging to the family Erysiphaceae (class-Ascomycetes).
2. Ascomycetes spores are harmful and it makes the crop vulnerable to its toxin.
3. Hence option (b) is correct: ascomycetes

Teacher's Note:
1. The stem becomes a powdery mass.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (b) Salmonella

Explanation:
1. Pullorum disease (Salmonellosis), a contagious disease of young birds, is caused by bacteria Salmonella pullorum.
2. It is usually transmitted by infected hens through their eggs.
3. Hence option (b) is correct: Salmonella

Teacher's Note:
1. Its symptoms are loss of appetite and thirst, diarrhoea with white faeces, drooping of wings etc.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (a) single stranded RNA not enclosed by protein coat.

Explanation:
1. Viroids are the smallest known agents of infectious diseases comprising of small single stranded molecule of RNA. Viroids lack capsid and have no proteins associated with them.
2. Hence option (a) is correct: single stranded RNA not enclosed by protein coat.

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (b) slimy mass of multinucleate protoplasm, having pseudopodia like structures for engulfing food, reproduction through fragmentation or zoospores.

Explanation:
1. Myxomycetes are acellular plasmodial slime molds i.e. a group of 4 fungus which reproduces through fragmentation or zoospore.
2. Hence option (b) is correct: slimy mass of multinucleate protoplasm, having pseudopodia like structures for engulfing food, reproduction through fragmentation or zoospores.

Teacher's Note:
1. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (d) bear basidiocarps

Explanation:
1. Rust, smut and mushroom bear short lived reproductive bodies called basidiocarps.
2. Hence option (d) is correct: bear basidiocarps

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (b) basidiocarps

Explanation:
1. Some basidiomycetes or club fungi (e.g., Agaricus campestris) produce basidiocarps.
2. These aerial structures also called mushrooms.
3. Hence option (b) is correct: basidiocarps

Teacher's Note:
1. They occur in rings called 'fairy rings'. Basidiocarps of some fungi are edible.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (d) Birds nest fungi and puffballs

Explanation:
1. Hence option (d) is correct: Birds nest fungi and puffballs

Teacher's Note:
1. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (c) Viroids consist of single-stranded RNA molecule.

Explanation:
1. Viroid is a small infective segment of nucleic acid, usually RNA. Prion is an infectious pathogenic agent devoid of nucleic acid and composed mainly of proteins.
2. Mycoplasmas lack a cell wall while Rickettsiae possess a cell wall.
3. Hence option (c) is correct: Viroids consist of single-stranded RNA molecule.

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (b) a linear chain of alternating NAG and NAM linked by β (1–4) linkage

Explanation:
1. The glycan part of peptidoglycan (murein) is a linear chain of alternating N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM).
2. They are joined by β (1–4) glycosidic bonds.
3. Hence option (b) is correct: a linear chain of alternating NAG and NAM linked by β (1–4) linkage

Teacher's Note:
1. The oligosaccharide component of bacterial cell wall consists of linear chains of alternating NAG and NAM linked by E (1 – 4) linkage.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (a) A – II; B – I; C – IV; D – III

Explanation:
1. A – II; B – I; C – IV; D – III.
2. Hence option (a) is correct: A – II; B – I; C – IV; D – III

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (c) Viruses cannot pass through bacterial filters.

Explanation:
1. Virus is a small infectious agent that replicates only inside the living cells of other organisms.
2. Viruses can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea.
3. Hence option (c) is correct: Viruses cannot pass through bacterial filters.

Teacher's Note:
1. Viruses can pass through bacterial proof filters as they are smaller than bacteria.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (a) Both Assertion and Reason are true and the Reason is a correct explanation of the Assertion.

Explanation:
1. Virus is a small infectious agent that can only replicate inside the cells of another organism.
2. Viruses are not considered as organisms as they have no independent machinery.
3. Hence option (a) is correct: Both Assertion and Reason are true and the Reason is a correct explanation of the Assertion.

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (c) Assertion is true but the Reason is false.

Explanation:
1. Aflatoxin, produced by Aspergillus flavus, is a carcinogenic fungal toxin.
2. The conidia not only causes allergies in human beings but also causes death of birds.
3. Hence option (c) is correct: Assertion is true but the Reason is false.

Teacher's Note:
1. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (b) Both Assertion and Reason are true but the Reason is not a correct explanation of the Assertion.

Explanation:
1. E. coli, Shigella sp. and Salmonella sp. causes diarrhoea.
2. It is due to intake of contaminated water.
3. Hence option (b) is correct: Both Assertion and Reason are true but the Reason is not a correct explanation of the Assertion.

Teacher's Note:
1. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (d) Both Assertion and Reason are false.

Explanation:
1. Neurospora belongs to class ascomycetes in which ascospores are produced in sac like asci . Neurospora is commonly called as pink or red bread mould.
2. It can be grown easily in laboratory conditions so, used in genetics experiments.
3. Hence option (d) is correct: Both Assertion and Reason are false.

Teacher's Note:
1. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.
2. Viruses, viroids and prions are acellular, so keep their features separate from bacteria and fungi.

Answer: (b) Both Assertion and Reason are true but the Reason is not a correct explanation of the Assertion.

Explanation:
1. In TMV, the chromosome consists of single stranded, linear RNA molecule coiled into a regular spiral.
2. TMV causes mosaic disease in tobacco and some other plants.
3. Hence option (b) is correct: Both Assertion and Reason are true but the Reason is not a correct explanation of the Assertion.

Teacher's Note:
1. C h a p t e r 3.
2. For microbes, learn one example for every feature: nutrition, reproduction, cell wall and disease.

Answer: (c) Assertion is true but the Reason is false.

Explanation:
1. Chemosynthesis is an autotrophic mode of nutrition, so the Assertion is true.
2. Chemoautotrophs obtain energy from oxidising inorganic substances and do not have chlorophyll, so the Reason is false.
3. Hence option (c) is correct: Assertion is true but the Reason is false.

Teacher's Note:
1. Chemoautotrophs developed the ability to synthesize organic molecules from inorganic raw materials.
2. Chlorophyll pigments are present in photoautotrophs.