Animal Kingdom – Core Vocabulary Flashcards

Vocabulary-style flashcards summarising key terms, characteristic features and representative examples across all major phyla discussed in the Animal Kingdom lecture notes. They aid rapid recall for NEET Biology and board examinations.

Animalia

Kingdom of multicellular, heterotrophic, eukaryotic organisms.

Porifera

Phylum of simple, sessile, aquatic animals (sponges) with a cellular level of organisation and a water canal system.

Ostia

Numerous tiny pores in sponges through which water enters the body.

Osculum

Large opening at the top of a sponge through which water exits.

Spongocoel

Central cavity of a sponge where water flows before leaving via the osculum.

Canal System (Porifera)

Network of water channels that transports water, food and oxygen through a sponge’s body.

Spicules

Microscopic skeletal elements of calcium carbonate or silica in sponges.

Spongin Fibres

Protein fibres forming part of the skeletal framework of many sponges.

Sycon

Common marine sponge; another name for Scypha.

Spongilla

Fresh-water sponge genus.

Euspongia

Bath sponge; a commercial, marine sponge.

Cnidaria (Coelenterata)

Phylum of diploblastic, tissue-level animals possessing cnidocytes.

Cnidocyte (Cnidoblast)

Specialised stinging cell of cnidarians that contains a nematocyst.

Nematocyst

Stinging capsule inside a cnidocyte used for defence, prey capture and anchorage.

Hypostome

Raised mouth region of many cnidarians.

Polyp

Sessile, cylindrical cnidarian body form (e.g., Hydra, Adamsia).

Medusa

Free-swimming, umbrella-shaped cnidarian form (e.g., Aurelia).

Metagenesis

Alternation between polyp and medusa generations in some cnidarians (e.g., Obelia).

Coral

Calcium-carbonate secreting cnidarian forming reefs (e.g., Meandrina).

Physalia

Portuguese Man-of-War; colonial, floating cnidarian.

Ctenophora

Exclusively marine phylum called comb jellies or sea walnuts.

Comb Plates

Eight external rows of ciliated plates used for locomotion in ctenophores.

Pleurobrachia

Example of ctenophore (sea gooseberry).

Diploblastic

Having two embryonic germ layers—ectoderm and endoderm—with mesoglea between.

Mesoglea

Non-cellular gelatinous layer between ectoderm and endoderm of diploblastic animals.

Triploblastic

Having three germ layers: ectoderm, mesoderm and endoderm.

Coelom

Body cavity lined by mesoderm.

Acoelomate

Animal lacking a body cavity (e.g., Platyhelminthes).

Pseudocoelomate

Animal with body cavity not fully lined by mesoderm (e.g., Nematoda).

Coelomate

Animal possessing a true coelom fully lined by mesoderm.

Platyhelminthes

Phylum of dorsoventrally flattened, acoelomate flatworms.

Hooks and Suckers

Attachment organs present in parasitic flatworms (taenia, fasciola).

Flame Cells

Excretory/osmoregulatory cells (protonephridia) of Platyhelminthes.

Planarian Regeneration

High ability of Planaria to regrow lost body parts.

Taenia

Tapeworm; endoparasitic platyhelminth.

Fasciola

Liver fluke; parasitic platyhelminth of sheep/humans.

Nematoda (Aschelminthes)

Phylum of cylindrical, unsegmented, pseudocoelomate roundworms.

Muscular Pharynx (Nematoda)

Well-developed sucking organ of nematodes.

Ascaris

Common intestinal roundworm of humans.

Wuchereria

Filarial worm causing elephantiasis.

Ancylostoma

Hookworm parasite of humans.

Annelida

Phylum of bilaterally symmetrical, segmented coelomates (earthworms, leeches).

Metamerism

True segmentation where external segments correspond to internal partitions.

Parapodia

Paired lateral appendages of Nereis used for swimming.

Nephridia

Excretory and osmoregulatory organs of annelids.

Double Ventral Nerve Cord

Typical nervous system of annelids (two cords on ventral side).

Hirudinaria

Leech genus; blood-sucking annelid.

Arthropoda

Largest animal phylum with chitinous exoskeleton and jointed appendages.

Chitinous Exoskeleton

Hard external covering of arthropods composed of chitin.

Book Lungs

Stacked, leaf-like respiratory organs in arachnid arthropods.

Book Gills

Respiratory plates in aquatic horseshoe crab (Limulus).

Tracheal System

Network of air tubes supplying oxygen in insects.

Malpighian Tubules

Excretory organs of insects that remove nitrogenous wastes.

Statocyst

Balance sensory organ in many crustaceans.

Locusta

Migratory locust; gregarious pest of crops.

Laccifer

Lac insect; secretes commercial shellac.

Limulus

King crab; living fossil arthropod.

Mollusca

Unsegmented, coelomate animals with a muscular foot, visceral hump and mantle.

Mantle

Soft fold of skin in molluscs that secretes the shell.

Mantle Cavity

Space between mantle and visceral hump containing feather-like gills.

Radula

File-like rasping organ in molluscs used for feeding.

Pearl Oyster (Pinctada)

Bivalve mollusc cultivated for pearls.

Pila

Apple snail; freshwater gastropod mollusc.

Loligo

Squid; fast-swimming cephalopod mollusc.

Sepia

Cuttlefish; cephalopod mollusc producing sepia ink.

Octopus

Eight-armed cephalopod; also called devilfish.

Dentalium

Tusk shell; scaphopod mollusc.

Chaetopleura

Chiton; polyplacophoran mollusc with eight shell plates.

Echinodermata

Marine, spiny-skinned phylum with pentaradial adult symmetry and water vascular system.

Ossicles

Calcareous endoskeletal plates of echinoderms.

Water Vascular System

Network of fluid-filled canals in echinoderms used in locomotion, feeding and respiration.

Asterias

Starfish genus in Echinodermata.

Echinus

Sea urchin genus.

Ophiura

Brittle star genus.

Cucumaria

Sea cucumber genus.

Antedon

Sea lily (crinoid) genus.

Hemichordata

Worm-like marine phylum with a stomochord and tripartite body.

Stomochord

Rudimentary, buccal diverticulum in hemichordates.

Proboscis–Collar–Trunk

Three body regions of hemichordates.

Open Circulatory System (Hemichordata)

Blood flows through open sinuses rather than closed vessels.

Balanoglossus

Acorn worm; typical hemichordate.

Chordata

Animals possessing a notochord, dorsal hollow nerve cord, pharyngeal gill slits, post-anal tail and ventral heart at some life stage.

Protochordata

Collective term for Urochordata and Cephalochordata.

Urochordata

Sub-phylum of tunicates with notochord in larval tail only.

Cephalochordata

Sub-phylum with persistent notochord along whole body (e.g., Branchiostoma).

Vertebrata

Sub-phylum where notochord is replaced by a vertebral column.

Cyclostomata

Jawless vertebrates (lampreys, hagfishes) that are ectoparasites on fishes.

Petromyzon

Lamprey; parasitic cyclostome.

Myxine

Hagfish; scavenging cyclostome.

Chondrichthyes

Cartilaginous fishes with persistent notochord, placoid scales and internal fertilisation.

Placoid Scales

Tooth-like dermal scales of cartilaginous fishes.

Torpedo

Electric ray possessing electric organs.

Trygon

Sting ray with poison sting in tail.

Pelvic Claspers

Copulatory organs on male cartilaginous fish pelvic fins.

Osteichthyes

Bony fishes with operculum-covered gills, air bladder and external fertilisation.

Operculum

Bony flap covering gills of bony fishes.

Ctenoid/Cycloid Scales

Thin, overlapping dermal scales of bony fishes.

Air Bladder

Gas-filled organ in most bony fishes aiding buoyancy.

Exocoetus

Flying fish; marine osteichthyan capable of gliding.

Hippocampus

Seahorse; male carries embryos in brood pouch.