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DIVERSITY OF NATURE SURVEY a KINGDOM ANIMALIA. Dr. Maxwell BILLAH Senior Lecturer, Department of Animal Biology & Conservation Science mxbillah@gmail.com. Characteristics of Kingdom Animalia. They are all multicellula r Other animal-like ones placed in Protoctista They are heterotrophic
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DIVERSITY OF NATURE SURVEYaKINGDOM ANIMALIA Dr. Maxwell BILLAH Senior Lecturer, Department of Animal Biology & Conservation Science mxbillah@gmail.com
Characteristics of Kingdom Animalia • They are all multicellular • Other animal-like ones placed in Protoctista • They are heterotrophic • This feature separates them from plants • Plants are autotrophic • Obtain their food by ingestion • This separates them from the fungi • Fungi are multicellular & heterotrophic, but obtain their food by absorption • Undigested food is egested from body
Have different types of feeding habits • Including carnivorous, herbivorous, omnivorous and parasitic modes of life • Often seek their food • Fungi always grow on their food • If they do, it requires locomotion • i.e. ability to move from one place to another • This in turn, requires a nervous system with sense organs and effectors
Locomotion of larger animals requires muscles & a skeleton(also for support) • There is tissue formation in all animals • One group of animals do not form true tissues – the Sponges • Tissue – group of cells (often similar in structure and origin), operating together to perform a specialized function • This called Differentiation or Division of Labour
Division of labour generally increases efficiency • Apart from tissues, there are higher levels of organization • Organ = number of tissues working together e.g. the stomach • System = group of organs working together e.g.. the digestive system • Various systems together make the organism.
Cells, tissues, organs and systems do not work in isolation - work in coordination • Coordination achieved by hormones and a nervous system • Development of more complex tissues, organs and systems is usually accompanied by; • basic changes in body plan • transport system within the body – blood • Blood = liquid tissue circulated by contractile vessels or a heart.
Animalia divided into 2 main groups; • Invertebrata (invertebrates) – Lower Animals • Vertebrata (Vertebrates) – Higher Animals
Kingdom Animalia • Phylum Porifera • Phylum Cnidaria • Phylum Platyhelminthes • Phylum Nematoda • Phylum Mollusca • Phylum Annelida • Phylum Arthropoda • Phylum Echinodermata • Phylum Chordata
Phylum Porifera (The Sponges) • The first and most primitive phylum of the Kingdom Animalia • Presence of numerous pores in body wall • And known as animals with spores • Some cell differentiation, but no tissue organization • Body has 2 layers of cells • Adults do not show locomotion • All marine, at deep sea or in coastal waters • Body frequently lacks symmetry
The Sponges – cont’d • All are filter feeders • Colourful, (orange, red, purple, green) • Single body cavity • Usually skeleton of calcareous or silica-rich spicules or horny fibre • No differentiated nervous system • Asexual reproduction by budding • All are hermaphrodite • Great regenerative power
Morphology and functions of sponge cells Section of Body of a Sponge Source: Anatomy of Animals - http://universe-review.ca/R10-33-anatomy.htm
Phylum Cnidaria (The Cnidarians) • Animals with stinging nettle or ‘Cnidos’ • Diploblastic i.e. body wall composed of 2 layers of cells; outer ectoderm & inner endoderm • Layersseparated by a structureless, gelatinouslayer of mesogloea • Tissue level of organization achieved • First group to have true tissues • Radially symmetrical
Body basically sac-shaped with single opening – mouth (for ingestion & egestion) • Single cavity within sac –enteron • Has 2 structural types, • polyps &medusae • Polyps sessile & may be solitary e.g. Hydra or colonial egObelia • Medusae free-swimming & solitary • Exhibit polymorphism
Classes of Cnidarians • Class Hydrozoa (Hydroids) E.g. Hydra & Obelia • Class Scyphozoa (Jellyfish) E.g. Aurelia (jellyfish) • Class Anthozoa (Corals & Sea anemones) – The “Flower Animals” EgMetridium, Corallium, Actinia & Madrepora • Class Cubozoa (“Scyphozoa cubed”) E.g. sea wasps & Box jellyfish
Distribution & Abundance • Anthozoan cnidarians are the most abundant, • Followed by; • Hydrozoans, • Scyphozoans and • Cubozoans
Platyhelminthes (The Flatworms) • Tripoblastic – presence of a 3rd layer, mesoderm, separating ectoderm from endoderm • Bilaterally symmetrical • Unsegmented • Acoelomate – space between endoderm and ectoderm filled with mesoderm • Flattened body shape • Mouth, but no anus
3 Classes of Flatworms • Class Turbellaria (Turbellarians) • Eg. Planaria • Class Trematoda (Flukes) • Eg. Fasciola (Liver fluke) • Eg. Schistosoma (Blood fluke) causes bilharzia • Class Cestoda (Tapeworms) • Eg. Taenia
Phylum Nematoda (Roundworms) • Triploblastic • Bilaterally symmetrical • Elongated round worms with pointed ends • Unsegmented • Alimentary canal with mouth and anus • Sexes separate • Some free-living • Anterior end shows some degree of cephalization i.e. development of a head
Important plant and animal parasites • Have simple internal body structure • E.g. Ascaris lumbricoides – common intestinal worm of humans and pigs • Wuchereria bancrfotii – infects human lymphatic system, causing elephantiasis
Phylum Mollusca (Molluscs) • 6 Classes of Molluscs • Unsegmented, TriploblasticCoelomate • Bilaterally symmetrical • Body soft & fleshy • Divided into head, ventral muscular foot & dorsal visceral hump • Skin (mantle) over hump secretes calcareous shell • No limbs
Class Monoplacophora Characteristics • Possess single symmetrical shell varying in shape from a flattened, shield-like plate to a short cone • Apex of shell anteriorly directed • Presence of broad flat foot separated from mantle on both sides by mantle cavity • Mouth located in front of foot, • Anus located in mantle cavity at posterior of the body • Serial repetition of pairs of gills (5-6 pairs) and foot retractor muscles (8 pairs)
Class Polyplacophora Class • Poly = many plates • Found in shallow marine waters • Adapted to adhering to rocks and shells • Body flattened, elongate, and oval • Body covered by a shell/plate with eight overlapping dorsal valves
Margin of each plate covered by mantle tissue or girdle, which is thick and stiff. • Surface may be covered by thin cuticle which may be smooth, scaly, calcareous, with bristles or spicules. • Head reduced, with no cephalic eyes or tentacles • Broad flattened ventral foot to facilitate adhesion to hard surface
Class Polyplacophora • Foot functions in adhesion as well as locomotion. • Roll into ball when dislodged • Microphagous feeders feeding on attached algae. • Radula is extended from mouth to rasp from surfaces. • Sensory structures: osphradia, • Dioecious, with a single median gonad.
Class: Gastropoda (Gastropods) • Terrestrial, marine & freshwater • Asymmetrical, Anus anterior • One piece shell, coiled due to rotation of hump during growth Large foot for locomotion • Head, eyes and sensory tentacles • Rasping tongue-like structure (radula) for feeding • Eg Helix aspera (land snail) • Patella (limpet), • Buccinum (whelk), Limax (slug)
Class: Pelecypoda (Bivalves) • Also known as Bivalvia or Lamellibranchia • Aquatic, Bilaterally symmetrical, • Filter feeders, and Anus posterior • Body laterally compressed and completely enclosed • Shell consists of 2 hinged halves (valves) • Head reduced in size, tentacles absent • Foot reduced in size & often used for burrowing in sand • EgMytilusedulis(marine mussel) • Ostrea (oyster)
Class: Cephalopoda (Cephalopods) • Presence highly-developed Head with tentacles with suckers • Aquatic, largest & most complex • Symmetry bilateral, Anus posterior • Shell reduced & internal or absent • Adapted for fast swimming. Foot modified to form part of head & tentacles • Well-developed eyes, Presence of Radula & horny beak • Sepia officinalis(cuttlefish), Loligo (squid) • Octopus vulgaris(octopus)
Phylum Annelida • Ringed or Segmented worms • Long and cylindrical • Segmented both internally and externally • Metameric segmentation – division of body transversely into a number of similar parts or segments • They have Chaetae or Hairs (made of Chitin) • Outer bodies covered with cuticle
3 Cell Body Layers (Triploblastic); • Cuticle, Epidermis and Dermis • Body divided into; • head or acron = prostomium bearing brain; • a trunk • terminal pygidium • They are Bilaterally symmetrical