![Porifera: The Cells
• Archaeocytes: These cells are totipotent, which means that they
can change into all of the other types of sponge cells.
Archaeocytes ingest and digest food caught by the choanocyte
collars and transport nutrients to the other cells of the sponge.
In some sponges, archaeocytes develop into gametes.
• Sclerocytes: The secretion of spicules is carried out by
sclerocytes. Other cells, called spongocytes, secrete the spongin
skeletal fibres when those are present.
• Myocytes and Porocytes: Poriferans do not have any muscle
cells, so their movement is rather limited. However, some
poriferan cells can contract in a similar fashion as muscle cells.
Myocytes and porocytes which surround canal openings and
pores can contract to regulate flow through the sponge.
• In an annotated diagram discuss the various cell types and their
functions in sponges [1-A4 page only] (submit by 11/02/21)](https://image.slidesharecdn.com/bio101-animalia2020-2021part1-250118081532-567cda0b/85/BIO-101-Animalia_2020-2021_part-1-pptx-n-18-320.jpg)
BIO 101- Animalia_2020-2021_part 1.pptx n
- 1. BIO 101: DIVERSITY OF LIVING ORGANISMS Dr. Justus Deikumah Conservation Biology nd Entomology KINGDOM ANIMALIA
- 2. Brief history of Classification of Living Things & Naming Organism • Taxonomy: The practice of classifying organisms - (Taxis = arrangement and nomos= method). • The modern taxonomic system was developed by the Swedish botanist Carolus Linnaeus (1707-1778). • He used simple physical characteristics of organisms to identify and differentiate between different species and is based on genetics. • Linnaeus developed a hierarchy of groups for taxonomy. • Each classifying group is called taxon (pl. taxa) and is subdivided into other groups.
- 3. The taxa in hierarchical order • Domain - Archaea, Eubacteria, Eukaryote • Kingdom - Plantae, Animalia, Fungi, Protista, Eubacteria (Monera), Archaebacteria • Phylum - Invertebrates, Vertebrates • Class - Fish, Bird, Mammal, Amphibian • Order - The Organism get its Energy? • Family - Special characteristics of the Organism and its relatives • Genus - First name of Organism • Species - Last name of Organism
- 4. The domain • The domain is the broadest category, while species is the most specific category available. • The taxon Domain was only introduced in 1990 by Carl Woese, as scientists reorganise things based on new discoveries and information. • For example, the common lizard in Ghana would be classified as follows: • Domain: Eukaryota • Kingdom: Animalia • Phylum: Chordata • Class: Reptilia • Order: Squamata • Suborder: Iguania • Family: Agamidae • Subfamily: Agaminae • Genus: Agama • Type species • Agama agama (Linnaeus, 1758)
- 5. Classification/Taxonomy Started by Aristotle with two Kingdoms (>2000yrs) Swedish botanist Carolus Linnaeus developed hierarchy (1735) -Domain (not included in Linn) -Kingdom -Phylum -Class -Order -Family -Genus -Species Robert Whittaker (1969) - 5 kingdoms, others 6
- 6. Cell features Viruses Prokaryotic cells Eukaryotic cells or RNA (Capsid)
- 7. Domains and Kingdoms of Living Organisms
- 9. KINGDOM ANIMALIA General Characteristics Eukaryotic – membrane-bound nucleus Multicellular - complex bodies Heterotrophs - ingest others for nutrients No cell walls - allows active movement Sexual reproduction (few asexual) Motile Sense Organs
- 10. The Nine Phyla of Animal Evolution Porifera Cnidaria Platyhelminthes sponges jellyfish flatworms roundworms Nematoda Mollusca Arthropoda Chordata Annelida Echinodermata mollusks multicellularity Ancestral Protist tissues bilateral symmetry body cavity segmentation coelom starfish vertebrates endoskeleton segmented worms insects spiders backbone specialization & body complexity specialized structure & function, muscle & nerve tissue distinct body plan; cephalization body complexity digestive & repro sys digestive sys body size redundancy, specialization, mobility body & brain size, mobility radial bilateral Invertebrates Vertebrates
- 11. Trends in animal evolution Invertebrates Vertebrates Porifera Chordata Body symmetry Body cavity (Coelom) Segmentation Cephalization
- 12. The nine Phyla Invertebrates Porifera Cnidaria Platyhelminthes Nematoda Mollusca Annelida Arthropoda Echinodermata Vertebrates Chordata Lecture coverage Features/X’tics Habitat Mode of feeding, locomotion and reproduction Importance
- 14. Phylum Porifera (Sponges) Most primitive animal Asymmetrical No head, tissue and organs Hollow with opening at one end and pores Some are soft and others really hard Various shapes and colours Features/Characteristics Mostly marine (few freshwater) Attached to rocks, coral reefs Habitat
- 15. Phylum Porifera (Sponges) Filter feeders – water and food through the pores Mode of feeding, locomotion and reproduction Some in symbiotic relations with algae Very few exceptiona l carnivores
- 16. Porifera: The Cells • Sponges have a cellular grade of organization. • They do not possess any structures that can be considered organs. • For instance, sponges do not have stomachs or kidneys. • Instead, sponge cells of various types are responsible for bodily functions, the day-to-day activities that sustain life.
- 17. Porifera: The Cells • Pinacocytes: "skin cells" lining the exterior of the sponge body wall. They are thin, leathery and tightly packed together. • Choanocytes: line the interior body walls with central flagellum that is surrounded by a collar of microvilli. Choanocytes are versatile cells. Their flagella beat to create the active pumping of water through the sponge, while the collars of the choanocytes are the primary areas that nutrients are absorbed into the sponge. Furthermore, in some sponges the choanoflagellates develop into gametes. • Mesenchyme: Between the two layers is a thin space called mesenchyme or mesohyl. The mesenchyme consists of a proteinaceous matrix, some cells, and spicules.
- 18. Porifera: The Cells • Archaeocytes: These cells are totipotent, which means that they can change into all of the other types of sponge cells. Archaeocytes ingest and digest food caught by the choanocyte collars and transport nutrients to the other cells of the sponge. In some sponges, archaeocytes develop into gametes. • Sclerocytes: The secretion of spicules is carried out by sclerocytes. Other cells, called spongocytes, secrete the spongin skeletal fibres when those are present. • Myocytes and Porocytes: Poriferans do not have any muscle cells, so their movement is rather limited. However, some poriferan cells can contract in a similar fashion as muscle cells. Myocytes and porocytes which surround canal openings and pores can contract to regulate flow through the sponge. • In an annotated diagram discuss the various cell types and their functions in sponges [1-A4 page only] (submit by 11/02/21)
- 19. Phylum Porifera (Sponges) Sessile (motile only at larval stage) Sexual and asexual reproduction Sexual - bisexual (hermaphrodite) but cross fertilization occurs as a rule Mode of feeding, locomotion and reproduction
- 20. Phylum Porifera (Sponges) Asexual reproduction (read on Budding, Fission, Formation of reduction bodies and Formation of gemmules- internal buds) Mode of feeding, locomotion and reproduction
- 21. Phylum Porifera (Sponges) Cycles nutrient in coral reef ecosystems Filters water to improve water quality Provide home for fishes and other marine organisms in coral reef systems Contribute to food web Contain potential pharmaceutical compounds Exploited as souvenir Importance
- 22. Phylum Cnidaria (Jellyfish, hydra, sea anemone, coral)
- 23. Have tissue but no organs Radial symmetry Tentacles with stinging cells surrounding opening/mouth Cnidocyte and nematocyst Exists as either: - polyp (sessile, vase-shaped, mouth-up, e.g. sea anemone) - medusa (motile, umbrella- Features/Characteristics
- 27. 3 Classes of Cnidaria • Class Hydrozoa • Class Scyphozoa • Class Anthozoa
- 28. Classes of Cnidaria Class Hydrozoa (water animal) - mostly marine (few fresh water), mainly colonial (few solitary), mostly medusa (few with both polyp and medusa stages), e.g. hydra, siphonophores Habitat
- 29. Classes of Cnidaria Class Scyphozoa (cup animals) - all marine, predominantly medusa, mouth surrounded by four oral arms, e.g. jellyfish Habitat
- 30. Classes of Cnidaria Class Anthozoa (flower animals) - All marine, solitary or colonial, sedentary, all polyps, oval mouth surrounded by tentacles resembling flower e.g. corals and sea anemones Habitat
- 31. Cnidaria Generally carnivores (predators) Capture animals by using poisonous stinging structures (nematocysts) on their tentacles Corals house algae (symbiotic colourful dinoflagellate) that provide nutrients Medusa move by muscular contractions Mode of feeding, locomotion and reproduction
- 32. Cnidaria Polyps primarily reproduce asexually by budding, some produce gametes (eggs and sperm) and reproduce sexually Medusae usually reproduce sexually using eggs and sperm Mode of feeding, locomotion and reproduction
- 33. Cnidaria Forms coral reefs – one of the most productive ecosystems in the world with high biodiversity and high fish productivity Exploited for ornamental trade Hard corals used as souvenir Importance
- 36. Complete digestive system-separate mouth and anus (2 openings) Pseudocoelomate ("false cavity“) Unsegmented Colorless Microscopic to several meters long May be free-living or parasitic Features/Characteristics
- 37. Parasitic nematodes live within a host Free-living nematodes live in marine, freshwater, or damp soil environments Habitat
- 38. Herbivores – eat plants Carnivores – predators (bacteria, inverts) Omnivores – eat both plants & animals Saprophagous -Eat dead organic matter (from animals only) Parasitic worms feed on the blood or tissue fluids of their hosts (insect, crustacean and vertebrate hosts) Mode of feeding
- 39. Two class Secernentea/ Chromadorea/ Phasmidea - (phasmids = sensory structures in tail) e.g. Wuchereria bancrofti (filarial worm), Ascaris lumbricoides (intestinal roundworms), Dracunculus medinensis (guinea worm), Necator (hookworm) Adenophorea/ Enoplea/ Aphasmidia e.g. Trichinella (trichina worms) Classes
- 40. Agric - as insects eaters and decomposers Filarial worms – elephantiasis Ascaris - humans (ascariasis) and pigs Guinea worm - dracunculiasis Trichina worms - trichinosis (contracted from eating undercooked pig products) Hookworms - helminthiases Importance
- 41. Phylum Annelida (segmented worms)
- 42. Coelomates Segmented bodies (metamerism = repeated segments) Features/Characteristics Parapodia (fleshy appendages) for locomotion, sensory purposes & respiration Cephalization Chitonous setae/ chaetae/bristles (except in leeches)
- 44. Annelida Classes The phylum consists of three classes Oligochaeta (commonly earthworms) Polychaeta (bristle worms) Hirudinea (leeches)
- 45. Class Oligochaeta Name means “few + long hairs”. Few setae per body segment. No head (but have brains), no parapodia Hermaphroditic (Clitella for egg deposition) Freshwater and in terrestrial soil Live in burrows and feeds on organic matter
- 46. Class Polychaeta (bristle worms) Name means “many + long hairs” Many setae per body segment Mostly marine and dioecious Parapodia for crawling, swimming, feeding and respiration Some feed by trapping suspended sediments on parapodia Others are predacious
- 47. Class Hirudinea (leeches) Mostly freshwater, some marine Bloodsucking carnivores - posterior and anterior suckers that secrete anticoagulants and consume blood No parapodia or setae Clitellum present Hermaphroditic
- 48. Terrestrial Oligochaetes important in soil fertility, soil aeration and forest development Aquatic Oligochaetes and Polychaetes used as bioindicators of ecosystem health Leeches used in modern medicine to cleanse blood and enhance healing after surgery Importance
- 50. Unsegmented soft body Coelomate – mantle cavity Bilaterally symmetry Body divided into head, muscular foot and visceral mass (internal organs) Body covered by mantle (a tissue) and a shell Gills and lungs Features/Characteristics
- 51. Most are aquatic, few terrestrial Habitat
- 52. Mollusca Classes Five classes of which three are prominent Bivalvia (clams, oysters, mussels) Gastropoda (Slugs, snails) Cephalopda (Squid, cuttlefish, octopus) Monoplacophora (limpets/barnacles) Polyplacophora (Chitons)
- 53. Class Bivalvia (bivalves) Shell made of two halves/valves (two shells??) hinged together Body laterally compressed No distinct head Either burrow or attach to substrate Mostly marine, few freshwater Clams, oysters, cockles, mussels
- 54. Class Gastropoda (gastropods) They possess a spiral shell The foot is large and flat Well developed head with tentacles and eyes Marine, freshwater and terrestrial Snails, slugs, periwinkles
- 55. Class Cephalopoda (cephalopods) Fused head and foot Foot modified into long tentacles or arms 8 or 10 tentacles with suckers for capturing prey- fast swimming marine predators Well-developed brains and show a high capacity for learning – considered intelligent Generally internal shell, nautilus has external Octopus, cuttlefish, squid, nautilus
- 56. Class Cephalopoda (cephalopods) Do you remember Paul the Octopus?
- 57. Assignment Write on the features/characteristics including habitat, mode of feeding, locomotion and reproduction of organisms of the Phylum Echinodermata, and the various classes of this phylum.
- 59. Segmented bodies with some or all of the segments bearing jointed appendages Hard exoskeleton (cuticle) composed of protein and chitin Molting of the cuticle is called ecdysis Extensive cephalization Head usually contains pairs of joint appendages, which are sensory and used in feeding Features/Characteristics
- 60. Most successful of all animal phyla based on diversity, distribution, and numbers Nearly one million species identified so far, mostly insects Aquatic members- gills for gas exchange; terrestrial members- tracheal system of branched tubes leading from surface Features/Characteristics
- 62. Classes The phylum consists of five classes Arachnida (spiders, scorpions, ticks, mites) Diplopoda (millipedes) Chilopoda (centepedes) Insecta (insects) Crustacea (crabs, lobsters, shrimps)
- 63. Class Arachnida Body having one or two main parts Six pairs of appendages (chelicerae, pedipalps and four pairs of walking legs) Mostly terrestrial
- 64. Class Diplopoda Body with distinct head bearing antenna and chewing mouth parts Segmented body with two pairs of walking legs per segment Terrestrial, herbivorous
- 65. Class Chilopoda Body with distinct head bearing large antennae and three pairs of mouthparts Appendages of first body segment modified as poisonous claws One pair of walking legs per segment Terrestrial, carnivorous
- 66. Class Insecta Body divided into head, thorax and abdomen Antenna present Mouth parts modified for chewing, sucking, etc. Usually with two pairs of wings and three pairs of legs Mostly terrestrial
- 67. Class Crustacea Body two or three parts Antennae present Chewing mouthparts Three or more pairs of legs Mostly marine
- 68. Importance Agriculture - Pollinators Food – Fisheries Industry Health – Insect borne diseases Etc.
- 70. Phylum Chordata
- 71. Notochord Dorsal nerve cord Pharyngeal pouches or gill slits Post-anal tail Features/Characteristics
- 72. Divided into three sub-phyla: Subphylum Urochordata (tunicates- sea squirts) Subphylum Cephalochordata (lancelets/ Amphioxus) Subphylum Vertebrata (vertebrates) Chordata
- 73. Larva posses all chordate characteristics Adults exhibit only Pharyngeal pouches Subphylum Urochordata (tunicates- sea squirts)
- 74. They retain all characteristic throughout life from larvae to adult Resemble small fish with a poorly developed head Subphylum Cephalochordata (Lancelets/Amphioxus)
- 75. Exhibits all characteristics of chordates Distinguishing characteristics Vertebral column or spine Cranium or skull that protects the brain Endoskeleton composed of bone or cartilage Subphylum Vertebrata (vertebrates)
- 76. Subphylum Vertebrata (vertebrates) postanal tail notochord hollow dorsal nerve cord pharyngeal pouches becomes brain & spinal cord becomes vertebrae becomes gills or Eustachian tube becomes tail or tailbone vertebrate embryo
- 77. Classes The phylum consists of seven classes Agnatha (jawless fishes) Chondrichthyes (cartilaginous fishes) Osteichthyes (bony fishes) Amphibia Reptilia Aves (birds) Mammalia
- 78. Long, eel-like bodies Lack jaws Paired fins Eg. Lampreys (parasitic) and hagfishes Superclass Agnatha (jawless fishes)
- 79. Class Chondrichthyes (cartilaginous fishes) Jaws Paired fins Skeleton of cartilage Gill slits E.g. sharks, rays, skates Superclass Gnathostomata (jawed fishes)
- 80. Class Osteichthyes (bony fishes) Jaws Most have a skeleton composed of bone Gill slits replaced by operculum E.g.??
- 82. Class Amphibia Skin is moist and permeable to gases and water Most lay eggs in water Most have an aquatic larval stage E.g.??
- 83. Class Reptilia Turtles, crocodiles, alligators, lizards and snakes Skin is dry and scaly Eggs that can be laid on land
- 84. CLASS AVES
- 85. Class Aves (birds) Adapted for flight through: - Feathers - Hollow bones Unique respiratory system – read about this
- 86. Taxonomy of Birds Kingdom–Animalia Phylum–Chordata Class–Aves Order–Passeriformes, Galliformes,… • All orders end in “iformes
- 87. What makes a bird a bird? Feathered Flight for most Bills/beaks Lay hard-shelled eggs Bipedal Endothermic
- 88. Some facts about Birds There are > 10,000 living species - the most speciose class of tetrapod vertebrates All present species belong to the subclass Neornithes They inhabit ecosystems across the globe, from the Arctic to the Antarctic Extant birds range in size from the 5cm bee hummingbird to the 2.75m Ostrich
- 89. • Birds descended from reptiles called Archaeopteryx some 140 million years ago.
- 91. Similarities between Reptiles and Birds • Keratinous scales cover the bodies of most non-avian reptiles, whereas feathers cover the bodies of birds. • However, keratinous scales cover the legs of birds, providing yet another clue of their reptilian ancestry. • The skulls of both birds and reptiles attach to the neck vertebrae at a single point called the occipital condyle. • This single point of attachment allows some birds and reptiles to rotate their heads farther than mammals can, as mammals have two occipital condyles • Both reptiles and birds have single middle ear bone compared to 3 in mammals
- 92. Differences between Reptiles and Birds • Birds are endothermic rather than ectothermic/poikilothermic • Birds have a four chambered heart which, among the living reptiles, only crocodylians have. • The others have three chambered hearts, with a poor separation between the ventricles • Birds have feathers, as well as scales. • Other reptiles have scales but no feathers. • The tail bones of a bird have been reduced and compressed into a tiny nub called a pygostyle
- 93. Taxonomy of birds • There are 2 sub-classes of birds under the class Aves Archaeornithes These are the ancient birds. They include reptile-like birds
- 94. Sub- class Neornithes • This include all other birds. • They have fused metacarpals • They have 13 or less tail vertebrae • 2 Sub-orders • Neognathae • Palaeonathae
- 95. Super order Neognathae • Include all flight birds. • There are about 19 orders • Orders end in ….iformes • E.g. Order Ciconiiformes (eg. Herons, Storks) • Find 2 examples from each of the 19 orders
- 96. Super order Palaeonathae • Includes all flightless birds. • They mostly cannot fly because they have unkeeled sterna and or weak wings
- 97. Are bats birds?
- 98. Class Mammalia Endothermy Hair Completely divided four chambered heart Milk produced from mammary gland Jawbone Specialized teeth
- 99. Order Monotremata Egg-laying mammals Most primitive of mammals Only three species Two anteaters and one platypus
- 100. Order Marsupialia Young develop in a pouch - E.g. Kangaroos and koalas
- 101. Placental Mammals Diverse group composed of at least 18 orders 95% of mammals are placental They live on land, in water and the air Humans – Order Primates, Sub-order Anthropoidea
- 102. Wrap up with evolutionary trends End of class Thank you