🔬 Biology · Class 11 · NEET
Animal Kingdom - Practice Questions with Answers 75 free MCQs on Animal Kingdom, each with its own worked answer and explanation. Phylum-level classification of the animal kingdom from Porifera to Chordata, based on body symmetry, coelom, and segmentation. One of the most example-heavy chapters for NEET.
Take the timed Animal Kingdom chapterwise test → 75 practice questions on Animal Kingdom , sorted Easy → Hard. Try each one first, then open its answer page for the worked explanation. Want the full theory first? Read the Animal Kingdom notes .
Body Plan Progression Across Phyla Porifera asymmetrical cellular level → Cnidaria radial, diploblastic tissue level → Platyhelminthes bilateral, acoelomate organ level → Nematoda pseudocoel. → Annelida+ true coelom organ system Each step adds organisational complexity: symmetry → germ layers → coelom type → organ systems Moving across the animal phyla, body organisation becomes progressively more complex: from no symmetry and cellular organisation (Porifera) through radial/diploblastic (Cnidaria), bilateral/acoelomate (Platyhelminthes), pseudocoelomate (Nematoda), to a true coelom with full organ systems (Annelida and beyond).
Easy - 25 questions Q1.
The system that circulates water through the body of a sponge is the:
A Water canal systemB Open blood systemC Tracheal air systemD Lateral line systemShow answer & explanation →
Q3.
The hard exoskeleton of an arthropod is made mainly of:
A Calcium carbonateB Silica granulesC ChitinD Keratin fibresShow answer & explanation →
Q4.
Jointed appendages are the defining feature of the phylum:
A MolluscaB AnnelidaC EchinodermataD ArthropodaShow answer & explanation →
Q5.
The blue, copper-containing respiratory pigment of many molluscs and arthropods is:
A HaemocyaninB HaemoglobinC MyoglobinD ChlorophyllShow answer & explanation →
Q14.
Which structure is characteristic of all members of phylum Chordata?
A RadulaB NotochordC Water vascular systemD CnidoblastsShow answer & explanation →
Q16.
Which class of vertebrates is characterized by the presence of feathers?
A ReptiliaB AvesC MammaliaD AmphibiaShow answer & explanation →
Q17.
Which of the following is an egg-laying mammal?
A Kangaroo, a marsupial that gives birth to underdeveloped youngB Platypus (Ornithorhynchus)C Camel, a placental mammal adapted to arid desert environmentsD Monkey, a placental primate with prolonged gestationShow answer & explanation →
Q18.
Which phylum includes comb jellies such as Pleurobrachia?
A CnidariaB CtenophoraC PoriferaD EchinodermataShow answer & explanation →
Q19.
Cockroach (Periplaneta) belongs to which phylum and class?
A Mollusca, GastropodaB Arthropoda, InsectaC Annelida, PolychaetaD Chordata, ReptiliaShow answer & explanation →
Q20.
What is the main excretory organ found in earthworms?
A Flame cellsB NephridiaC Malpighian tubulesD Green glandsShow answer & explanation →
Q21.
Which animal phylum shows radial symmetry?
A CoelenterataB the phylum AnnelidaC only Arthropoda groupD a class called AvesShow answer & explanation →
Q22.
What is the level of organisation in Porifera?
A Cellular levelB the organ system levelC a tissue-grade levelD only organ level typeShow answer & explanation →
Q23.
Which phylum do sponges belong to?
A PoriferaB the phylum CnidariaC only group MolluscaD a set called AvesShow answer & explanation →
Q24.
Animals with a notochord belong to which phylum?
A ChordataB the phylum AnnelidaC only EchinodermataD a group ArthropodaShow answer & explanation →
Q25.
Which animals are commonly called flatworms?
A PlatyhelminthesB the roundworm groupC only the earthwormsD a set of jellyfishShow answer & explanation →
Medium - 25 questions Q26.
In a sponge, water finally leaves the central cavity through a large opening called the:
A The ostiumB The osculumC The blastoporeD The nephridioporeShow answer & explanation →
Q27.
Ascaris shows marked sexual dimorphism, which means that:
A It can change its sexB It reproduces only asexuallyC Males and females differ in formD Each worm is a hermaphroditeShow answer & explanation →
Q28.
In most molluscs the soft body is protected by a calcareous shell secreted by the:
A The radulaB The muscular footC The gill filamentsD The mantleShow answer & explanation →
Q29.
The excretory organs of insects such as the cockroach are the:
A Malpighian tubulesB Flame cellsC NephridiaD Green glandsShow answer & explanation →
Q30.
In tunicates (Urochordata), the notochord is restricted to the:
A Adult trunk regionB Larval tail onlyC Entire body alwaysD Gill region onlyShow answer & explanation →
Q31.
Which feature distinguishes pseudocoelomates from true coelomates?
A Pseudocoelomates have no body cavityB Pseudocoelomates have a body cavity that is not lined by mesodermC Pseudocoelomates have a body cavity lined largely by mesodermD There is no difference, the terms are interchangeableShow answer & explanation →
Q32.
Animals showing diploblastic organization, like Hydra, have body walls made of how many germ layers?
A One layer with no distinctionB Two layers: ectoderm and endodermC Three layers: ectoderm, mesoderm, and endodermD Four distinct layersShow answer & explanation →
Q33.
Which of the following correctly matches the phylum with its type of symmetry?
A Porifera, exhibiting bilateral body symmetry overallB Echinodermata adults, radial symmetryC Annelida, exhibiting radial body symmetry overallD Platyhelminthes, lacking any defined body symmetryShow answer & explanation →
Q34.
What is the function of cnidoblasts (cnidocytes) found in Cnidaria?
A Digestion of food in the gastrovascular cavityB Excretion of nitrogenous wastesC Defense and capturing of prey via stinging cellsD Locomotion by water expulsionShow answer & explanation →
Q35.
Which type of circulatory system is found in Arthropoda?
A Closed circulatory systemB Open circulatory systemC No circulatory systemD Double circulation onlyShow answer & explanation →
Q36.
The water vascular system, used for locomotion and respiration, is a unique feature of which phylum?
A MolluscaB EchinodermataC HemichordataD AnnelidaShow answer & explanation →
Q37.
Which structure in molluscs is used as a rasping organ for feeding?
A RadulaB MantleC SpiculeD MadreporiteShow answer & explanation →
Q38.
Which subphylum or group of Chordata retains the notochord throughout life, extending from head to tail?
A UrochordataB CephalochordataC Vertebrata onlyD HemichordataShow answer & explanation →
Q39.
Which of the following animals lacks separate sexes (is hermaphroditic)?
A Ascaris, a parasitic roundworm speciesB Earthworm (Pheretima)C Periplaneta, the common cockroachD Asterias, a marine starfish speciesShow answer & explanation →
Q40.
Which class of fishes lacks an operculum (gill cover) over the gill slits?
A OsteichthyesB ChondrichthyesC AmphibiaD CyclostomataShow answer & explanation →
Q41.
Which class of vertebrates typically has a three-chambered heart, with crocodiles being a notable exception?
A AmphibiaB ReptiliaC AvesD MammaliaShow answer & explanation →
Q42.
Which phylum was previously considered a subphylum of Chordata but is now treated as a separate phylum?
A CephalochordataB UrochordataC HemichordataD EchinodermataShow answer & explanation →
Q43.
Which of these features is shared by both Annelida and Arthropoda?
A Open circulatory system in bothB Metameric segmentation of the bodyC Absence of a coelomD Exoskeleton made of chitin in bothShow answer & explanation →
Q44.
Mammary glands, hair on skin, and a four-chambered heart are characteristic features of which class?
A AvesB ReptiliaC MammaliaD AmphibiaShow answer & explanation →
Q45.
What kind of body cavity does a true coelomate have?
A Mesoderm-lined cavityB a cavity with no lining at allC only an ectoderm-lined spaceD a plain pseudocoelom pocketShow answer & explanation →
Q46.
Which phylum has a water vascular system?
A EchinodermataB the phylum ArthropodaC only Mollusca membersD a group called AvesShow answer & explanation →
Q47.
In which phylum does metameric segmentation first appear?
A AnnelidaB the phylum PoriferaC only CoelenterataD a class of ReptiliaShow answer & explanation →
Q48.
Which feature is unique to phylum Arthropoda?
A Jointed appendagesB a soft unsegmented bodyC only a radial symmetryD the presence of setaeShow answer & explanation →
Q49.
What is the excretory structure in Platyhelminthes?
A Flame cellsB the green glandsC only nephridiaD a set of kidneysShow answer & explanation →
Q50.
Which animals possess stinging nematocysts?
A CnidariansB the roundworms groupC only the molluscsD a set of spongesShow answer & explanation →
Hard - 25 questions Q51.
Retrogressive metamorphosis, in which the larva is more advanced than the adult, occurs in:
A CephalochordataB HemichordataC UrochordataD CyclostomataShow answer & explanation →
Q52.
Air sacs linked to the lungs that lighten the body for flight are a special feature of:
A ReptilesB AmphibiansC Cartilaginous fishD BirdsShow answer & explanation →
Q53.
The lateral line sensory system, which detects water currents and vibrations, is typical of:
A FishesB ReptilesC Adult birdsD Land mammalsShow answer & explanation →
Q54.
Poikilothermic (cold-blooded) vertebrates include fishes, amphibians and:
A Only mammalsB ReptilesC Birds onlyD No other groupShow answer & explanation →
Q55.
Sponges survive bad conditions and reproduce asexually by forming resistant internal buds called:
A CystsB NymphsC GemmulesD LarvaeShow answer & explanation →
Q56.
An animal has a triploblastic body, bilateral symmetry, a pseudocoelom, and a complete digestive system but lacks circulatory and respiratory systems. Which phylum does it most likely belong to?
A PlatyhelminthesB NematodaC AnnelidaD MolluscaShow answer & explanation →
Q57.
Which set correctly distinguishes Cephalochordata from Urochordata?
A Cephalochordata retains the notochord only in the larval tail before resorption at metamorphosis; Urochordata retains it for lifeB Cephalochordata retains the notochord from head to tail throughout life; Urochordata retains it only in the larval tailC Both groups retain a fully ossified vertebral column replacing the notochord in adultsD Neither group develops a notochord at any embryonic or adult stageShow answer & explanation →
Q58.
Which combination of features would correctly identify an organism as belonging to class Chondrichthyes rather than Osteichthyes?
A Bony endoskeleton, gills covered by operculum, terminal mouth according to most researchersB Cartilaginous endoskeleton, ventrally placed mouth, gill slits without operculumC Cartilaginous endoskeleton, four-chambered heart, feathers in the majority of cases studiedD Bony endoskeleton, placoid scales, dorsal mouth as widely reported in standard practiceShow answer & explanation →
Q59.
Why is Balanoglossus no longer classified within phylum Chordata despite historically being grouped with it?
A It lacks bilateral symmetry, instead showing radial symmetry typical of cnidarians under most conditions encounteredB The presence of a true notochord in Balanoglossus is doubtful, so Hemichordata is now a separate phylumC It possesses a closed circulatory system, unlike the open system found in true chordates as commonly observed in practiceD It develops without a coelomic body cavity during embryogenesis in many documented cases according to conventional understandingShow answer & explanation →
Q60.
A marine animal shows radial symmetry as an adult, bilateral symmetry as a larva, an endoskeleton of calcareous ossicles, and no distinct excretory system. To which phylum does it belong?
A CnidariaB MolluscaC EchinodermataD HemichordataShow answer & explanation →
Q61.
Which of the following is true regarding metagenesis as observed in Obelia?
A It refers to alternation between asexual polyp and sexual medusa forms within the life cycleB It refers to the formation of a water vascular system used for locomotion in echinodermsC It is a type of asexual budding and fragmentation seen exclusively in spongesD It describes the alternation between haploid gametophyte and diploid sporophyte plant generationsShow answer & explanation →
Q62.
Which statement correctly differentiates the levels of organization across early phyla?
A Porifera shows organ-system level with coordinated organ function, Cnidaria shows mainly cellular levelB Porifera shows cellular level, Cnidaria shows tissue level, Platyhelminthes shows organ levelC All three phyla independently evolved a largely coordinated organ-system level of organizationD Cnidaria shows organ-system level of organization that exceeds that of PlatyhelminthesShow answer & explanation →
Q63.
Which feature is unique to phylum Hemichordata that helps separate it structurally from true Chordata?
A Presence of a dorsal hollow nerve cord identical to vertebrates in routine practiceB A body divided into proboscis, collar, and trunk, with a doubtful notochordC Possession of a vertebral column overall in most cases under typical conditionsD Presence of paired appendages like fins according to standard textbooksShow answer & explanation →
Q64.
Which of the following correctly lists an order of increasing structural complexity in body cavity organization?
A Coelomate, pseudocoelomate, acoelomateB Acoelomate, pseudocoelomate, coelomateC Pseudocoelomate, coelomate, acoelomateD Coelomate, acoelomate, pseudocoelomateShow answer & explanation →
Q65.
Which feature distinguishes the class Cyclostomata from Chondrichthyes?
A Cyclostomata have jaws, Chondrichthyes are jawless in general practice as commonly describedB Cyclostomata are jawless and ectoparasitic, Chondrichthyes have jaws and are mostly predaceousC Cyclostomata have a bony endoskeleton, Chondrichthyes have a cartilaginous one in most textbook accountsD Cyclostomata live mainly in deserts, Chondrichthyes live mainly in rivers during normal conditionsShow answer & explanation →
Q66.
Why are sea cucumbers (Holothuria) and sea urchins (Echinus) both grouped in phylum Echinodermata despite differing body shapes?
A Both share an open circulatory system and jointed legs adapted for benthic crawling as generally observedB Both have an endoskeleton of calcareous ossicles and a water vascular system with tube feetC Both reproduce mainly by asexual budding without any sexual phase in typical laboratory settingsD Both lack any skeletal structure and rely on a soft protective mantle under usual circumstancesShow answer & explanation →
Q67.
Which phylum is characterised by a pseudocoelom?
A AschelminthesB the phylum AnnelidaC only PlatyhelminthesD a group of chordatesShow answer & explanation →
Q68.
Presence of pharyngeal gill slits at some stage marks which group?
A ChordatesB the phylum AnnelidaC only ArthropodaD a set of poriferansShow answer & explanation →
Q69.
Which vertebrate class has a two-chambered heart?
A PiscesB the class MammaliaC only class AvesD a group ReptiliaShow answer & explanation →
Q70.
Which respiratory structures do insects use?
A TracheaeB the book lungs onlyC only their gillsD a set of nephridiaShow answer & explanation →
Q71.
Comb plates for locomotion are found in which phylum?
A CtenophoraB the phylum CnidariaC only EchinodermataD a group of annelidsShow answer & explanation →
Q72.
Which trait makes birds endothermic?
A Warm-blooded bodyB a cold-blooded systemC only a scaly coverD the moist soft skinShow answer & explanation →
Q73.
Which phylum is acoelomate with organ-system organisation?
A PlatyhelminthesB the phylum AnnelidaC only AschelminthesD a group ArthropodaShow answer & explanation →
Q74.
Which group has a closed circulatory system?
A AnnelidaB the phylum ArthropodaC only MolluscaD a set of spongesShow answer & explanation →
Q75.
Radial symmetry with tube feet describes which adults?
A EchinodermsB the arthropod groupC only the annelidsD a set of chordatesShow answer & explanation →