🔬 Biology · Class 11 · NEET
Biological Classification - Practice Questions with Answers 75 free MCQs on Biological Classification, each with its own worked answer and explanation. Whittaker's five kingdom system covering Monera, Protista, Fungi, plus viruses, viroids, and lichens. A foundational NEET chapter on how living organisms are grouped.
Take the timed Biological Classification chapterwise test → 75 practice questions on Biological Classification , sorted Easy → Hard. Try each one first, then open its answer page for the worked explanation. Want the full theory first? Read the Biological Classification notes .
Whittaker's Five Kingdoms Monera prokaryotes Protista unicell. eukaryotes Fungi chitin wall Plantae cellulose wall Animalia no wall NOT in any kingdom: Viruses (non-cellular), Viroids (RNA, no coat), Lichens (alga+fungus symbiosis) Classification criteria: cell structure, nutrition mode, body organisation, reproduction, phylogeny Whittaker's five-kingdom system (1969) groups all cellular life by cell structure and nutrition; viruses, viroids, and lichens fall outside this system entirely since they aren't independently classifiable as one of the five.
Easy - 25 questions Q1.
Whittaker's five-kingdom system grouped organisms using cell structure, body organisation and:
A Mode of nutritionB Rate of respirationC Type of excretionD Speed of locomotionShow answer & explanation →
Q2.
The mode of nutrition seen in Euglena is:
A Purely parasitic feedingB Mixotrophic - both modesC Only chemosyntheticD Purely saprophytic feedingShow answer & explanation →
Q6.
Who proposed the five kingdom classification system?
A Carl LinnaeusB R.H. WhittakerC Charles DarwinD Robert HookeShow answer & explanation →
Q10.
Lichens are a symbiotic association between
A Two species of fungiB Algae and fungiC Bacteria and algaeD Fungi and bryophytesShow answer & explanation →
Q12.
Which of the following is a viroid disease?
A Tobacco mosaic diseaseB Potato spindle tuber diseaseC Mad cow diseaseD Rust of wheatShow answer & explanation →
Q13.
Viruses contain genetic material in the form of
A Only DNAB Only RNAC Either DNA or RNA, never bothD Both DNA and RNA togetherShow answer & explanation →
Q16.
Yeast (Saccharomyces) belongs to which fungal class?
A PhycomycetesB AscomycetesC BasidiomycetesD DeuteromycetesShow answer & explanation →
Q17.
Bacteria that thrive in extremely hot and acidic environments are called
A HalophilesB MethanogensC ThermoacidophilesD CyanobacteriaShow answer & explanation →
Q18.
Which of the following organisms is responsible for producing biogas, and survives in marshy areas and the gut of ruminants?
A MethanogensB NostocC PenicilliumD PlasmodiumShow answer & explanation →
Q20.
The protein coat that covers the genetic material of a virus is called the
A EnvelopeB CapsidC CapsomereD CytoskeletonShow answer & explanation →
Q21.
The widely used five-kingdom system of classification was proposed by:
A R. H. WhittakerB Carolus LinnaeusC Charles DarwinD Gregor MendelShow answer & explanation →
Q24.
Organisms whose cells lack a true, membrane-bound nucleus are called:
A prokaryotesB eukaryotesC fungiD green plantsShow answer & explanation →
Medium - 25 questions Q26.
Aspergillus and Penicillium are placed in which class of fungi?
A BasidiomycetesB AscomycetesC ZygomycetesD PhycomycetesShow answer & explanation →
Q27.
A kingdom of uni- and multicellular heterotrophs whose cell walls contain chitin is:
A MoneraB ProtistaC FungiD PlantaeShow answer & explanation →
Q28.
When two haploid nuclei from the parents share a cell without fusing, the stage is a:
A A diploid zygote cellB A single haploid sporeC A fused multinucleate massD A dikaryon (n+n) cellShow answer & explanation →
Q30.
Amoeboid, flagellated, ciliated and sporozoan forms are all members of the kingdom:
A MoneraB ProtistaC FungiD AnimaliaShow answer & explanation →
Q31.
Which of the following correctly distinguishes archaebacteria from eubacteria?
A Archaebacteria largely lack a peptidoglycan-based cell wall found in most eubacteria speciesB Archaebacteria have a distinct cell wall structure allowing survival in extreme habitats, eubacteria do notC Eubacteria are mostly photosynthetic, while archaebacteria rarely carry out photosynthesisD Archaebacteria possess a true membrane-bound nucleus while eubacteria remain strictly prokaryotic organismsShow answer & explanation →
Q32.
Slime moulds are classified under Protista mainly because
A They are mainly photosynthetic, deriving energy directly from chlorophyll pigmentsB They form an aggregation called plasmodium and are saprophyticC They possess a rigid cellulose cell wall similar to that of green algaeD They reproduce mainly through prokaryotic-style binary fissionShow answer & explanation →
Q33.
Dinoflagellates are characterized by which of the following features?
A Two flagella, one lateral and one longitudinal, with stiff cellulose plates on the cell wallB Largely absent flagella combined with a chitinous exoskeleton-like cell wall structureC Locomotion mainly by amoeboid movement using extending pseudopodia structuresD An infectious spore-forming stage characteristic of their typical parasitic life cycleShow answer & explanation →
Q34.
Which class of fungi is also called the imperfect fungi because their sexual stage is unknown?
A PhycomycetesB AscomycetesC BasidiomycetesD DeuteromycetesShow answer & explanation →
Q35.
In the fungal sexual cycle, the correct sequence of events is
A Karyogamy, meiosis, plasmogamyB Plasmogamy, karyogamy, meiosisC Meiosis, plasmogamy, karyogamyD Plasmogamy, meiosis, karyogamyShow answer & explanation →
Q36.
Rhizopus (bread mould) belongs to which class of fungi and shows what type of mycelium?
A Ascomycetes, septate myceliumB Phycomycetes, coenocytic myceliumC Basidiomycetes, branched myceliumD Deuteromycetes, septate myceliumShow answer & explanation →
Q37.
Which statement about mycoplasma is correct?
A They possess an unusually thick peptidoglycan cell wall structureB They are the smallest living cells and lack a cell wallC They are obligate photosynthetic autotrophs lacking any cell wallD They belong specifically to kingdom Protista among microorganismsShow answer & explanation →
Q38.
Why are viruses not included in any of the five kingdoms?
A Because their size is below the resolution limit of even electron microscopyB Because they show no signs of life outside a living host cell and are non-cellularC Because their host range is restricted largely to plant cells, excluding animalsD Because they largely lack any form of nucleic acid genetic materialShow answer & explanation →
Q39.
Who demonstrated that viruses could be crystallized and consist largely of protein?
A D.J. IvanowskyB M.W. BeijerinckC W.M. StanleyD Louis PasteurShow answer & explanation →
Q40.
What is the main difference between a virus and a viroid?
A Viroids possess a capsid protein coat that surrounding viruses largely lackB Viroids lack the protein coat present in viruses and have smaller RNAC Viroids carry mainly double-stranded DNA genomes while viruses generally carry RNAD Viroid particles are consistently larger in physical size than virus particlesShow answer & explanation →
Q41.
Plant viruses are typically composed of which type of nucleic acid?
A Single-stranded RNAB Double-stranded DNA mainlyC Double-stranded RNA mainlyD Usually both DNA and RNAShow answer & explanation →
Q43.
Most fungi obtain their food by:
A absorption (heterotrophic)B green-plant photosynthesisC chemical chemosynthesisD fixing free nitrogenShow answer & explanation →
Q47.
Viruses are described as ___ because they can reproduce only inside a host cell:
A obligate parasitesB free autotrophsC free-living cellsD soil decomposersShow answer & explanation →
Q48.
The kingdom Protista consists mostly of ___ organisms:
A unicellular eukaryoticB large multicellularC simple prokaryoticD thread-like fungalShow answer & explanation →
Q49.
A close symbiotic association between an alga and a fungus is called a:
A lichenB mycorrhizaC biofilmD root noduleShow answer & explanation →
Q50.
Bacteria that require oxygen for their metabolism are described as:
A aerobicB anaerobicC facultativeD photosyntheticShow answer & explanation →
Hard - 25 questions Q51.
In a lichen, the photosynthetic algal partner is known as the:
A The mycobiontB The symbiontC The phycobiontD The basidiocarpShow answer & explanation →
Q52.
The contractile vacuole of freshwater protists such as Amoeba functions mainly in:
A Storing reserve foodB Exchange of gasesC Cell locomotionD OsmoregulationShow answer & explanation →
Q53.
The two-piece silica cell wall of a diatom is called the:
A The frustuleB The capsidC The pellicleD The mantleShow answer & explanation →
Q54.
Sporozoans such as Plasmodium are chiefly characterised by:
A Bearing a fringe of many ciliaB A spore-forming parasitic stageC Moving by many pseudopodiaD Swimming with two long flagellaShow answer & explanation →
Q55.
Lichens act as pioneer colonisers in ecological succession on bare rock because they:
A Fix nitrogen from the air onlyB Are fast-growing green herbsC Can colonise bare rock and form soilD Grow only in unpolluted airShow answer & explanation →
Q56.
A student observes an organism with a peptidoglycan cell wall, no membrane-bound nucleus, and the ability to fix nitrogen using heterocysts. This organism most likely belongs to which group?
A Archaebacteria (Archaea)B Cyanobacteria (Eubacteria)C Chrysophytes (golden algae and diatoms)D Slime moulds (Myxomycota)Show answer & explanation →
Q57.
Why was the two-kingdom classification (Plantae and Animalia) considered inadequate?
A It did not distinguish eukaryotes from prokaryotes, unicellular from multicellular, or photosynthetic from non-photosynthetic organismsB It mistakenly placed every known bacterial species directly within kingdom Animalia alongside multicellular animals in most casesC It systematically and largely excluded flowering angiosperm plants from being classified within kingdom Plantae under typical conditionsD It relied mainly on molecular DNA sequencing data that was technologically unavailable at the time it was first proposed according to standard textbooksShow answer & explanation →
Q58.
Which combination correctly matches the fungal class with both its reproductive spore type and an example?
A Phycomycetes, basidiospores, AgaricusB Ascomycetes, ascospores, PenicilliumC Basidiomycetes, conidia, AspergillusD Deuteromycetes, ascospores, AlternariaShow answer & explanation →
Q59.
Lichens are used as pollution indicators because
A They grow rapidly in industrial smokeB They are extremely sensitive and do not grow in polluted areasC They turn color only in clean air, never in polluted regionsD They require high sulfur dioxide levels to surviveShow answer & explanation →
Q60.
Prions, associated with diseases such as mad cow disease, differ from viruses and viroids in that they are
A Composed entirely of double-stranded DNA packaged within a protective capsidB Abnormally folded infectious protein particles with no nucleic acidC Small RNA molecules enclosed within a protective protein coatD Fragments of peptidoglycan derived from the bacterial cell wallShow answer & explanation →
Q61.
Which feature is shared by chrysophytes and dinoflagellates but distinguishes both from slime moulds?
A Both groups are mainly photosynthetic with components in their cell coveringB Both groups feed as heterotrophic decomposers breaking down dead organic matterC Both groups pass through an aggregated plasmodium stage during their life cycleD Both groups completely lack any form of protective cell coveringShow answer & explanation →
Q62.
Which of these is an example of a symbiotic relationship found in kingdom Fungi (other than a lichen)?
A Mycorrhiza, an association between fungi and plant rootsB Plasmodium formation occurring during the aggregative phase of slime mouldsC Heterocyst formation enabling nitrogen fixation in the cyanobacterium NostocD Conjugation, the process of genetic material exchange between eubacterial cellsShow answer & explanation →
Q63.
Entamoeba histolytica and Trypanosoma both belong to kingdom Protista but differ mainly in their
A Mode of locomotion, pseudopodia versus flagellaB Cell wall composition, cellulose versus chitinC Mode of nutrition, autotrophic versus chemosyntheticD Habitat, exclusively marine versus exclusively terrestrialShow answer & explanation →
Q64.
A fungal hypha is described as coenocytic. This means
A It is divided into compartments by septa in general practiceB It is multinucleate and lacks septa (cross walls)C It produces mainly sexual spores as commonly describedD It is found mainly in Basidiomycetes in most textbook accountsShow answer & explanation →
Q65.
Considering reproduction in Monera, which mechanism allows genetic material transfer between bacteria without cell fusion?
A Plasmogamy during normal conditions as generally observedB Conjugation, transduction, or transformationC Gametic fusion followed by meiosis in typical laboratory settingsD Formation of a plasmodium under usual circumstancesShow answer & explanation →
Q68.
Bacteria that thrive in extreme habitats such as hot springs and salt lakes are the:
A archaebacteriaB common eubacteriaC cyanobacteriaD simple protistsShow answer & explanation →
Q69.
Mycoplasmas are unusual bacteria because they completely lack a:
A cell wallB nucleusC ribosomeD cytoplasmShow answer & explanation →
Q70.
The mode of nutrition in which an organism feeds on dead and decaying matter is:
A saprophyticB parasiticC autotrophicD holozoicShow answer & explanation →
Q71.
The dinoflagellates that cause "red tides" in the sea belong to the kingdom:
A ProtistaB MoneraC FungiD PlantaeShow answer & explanation →
Q73.
The reproductive spores of most fungi are:
A non-motileB always flagellatedC photosyntheticD nitrogen-fixingShow answer & explanation →
Q74.
A virus that specifically infects bacteria is called a:
A bacteriophageB a protozoanC a lichenD a mycoplasmaShow answer & explanation →