zoology

• Nervous system


  The organ system that integrates all body functions through transmission and processing of information from the external environment or within the organism's body
• Nervous system


  • Major divisions include the central nervous system (CNS) and the peripheral nervous system (PNS)
• Central nervous system (CNS)

  Includes the brain and spinal cord
• Cranial nerves


  • CN 01 = Olfactory (Sensory)
  • CN 02 = Optic (Sensory)
  • CN 03 = Oculomotor (Motor)
  • CN 04 = Trochlear (Motor)
  • CN 05 = Trigeminal (Both)
  • CN 06 = Abducens (Motor)
  • CN 07 = Facial (Both)
  • CN 08 = Auditory (Sensory)
  • CN 09 = Glossopharyngeal (Both)
  • CN 10 = Vagus (Both)
  • CN 11 = Accessory (Motor)
  • CN 12 = Hypoglossal (Motor)
• Peripheral nervous system (PNS)


  Includes the sympathetic trunk and spinal nerves
• Zoological Nomenclature


  Assigning formal names to hierarchical classifications, names for different entities or groups, written in a standard way for easy recognition
• Biologists use the "BINOMIAL SYSTEM" by Carolus Linnaeus
• Animal-like Protists


  • Descendants from forms that gave rise to multicellular organisms
  • Carry out life processes within the cell
  • Diverse in nutrition and modes of existence
  • Capable of locomotion and various reproduction methods
• Phylum Porifera


  Sponges belonging to this phylum
• Phylum Cnidaria


  Includes jellyfish, corals, and sea anemones
• Nomenclature


  Scientific names follow internationally agreed rules, published in respective "Codes of Nomenclature"
• Binomial Nomenclature


  Written in italics with genus and species names, species name follows a genus name or its initial, includes the scientific name and the person who described the species
• Origins of Scientific Names

  • Descriptive names based on characteristics
  • Scientist's names associated with organisms
  • Geographic places or organizations linked to names
• Natural System of Classification

  Biologists aim for a natural classification system, inferring the diversity of organisms
• Linnaean Hierarchy


  Classification hierarchy from species to kingdom by Linnaeus
• Domains of Life by Carl Woese


  Three domains: Archaea, Bacteria, Eukarya, Carl Woese's RNA sequence comparison led to classification
• Kingdoms of Life


  • Archaea
  • Bacteria
  • Protista
  • Fungi
  • Plantae
  • Animalia
• Parade of Invertebrates


  • Porifera
  • Cnidaria
  • Platyhelminthes
  • Nematoda
  • Annelida
  • Mollusca
  • Arthropoda
  • Echinodermata
• Animal-like Protists


  • Protozoans with diverse modes of nutrition and existence
  • Capable of locomotion and various reproduction methods
• Phylum Amoebozoa


  Includes Amoeba
• Phylum Euglenida


  Includes Euglena
• Phylum Kinetoplastida


  Includes Trypanosoma
• Phylum Granuloreticulosa


  Includes Foraminifera
• Phylum Apicomplexa


  Includes Plasmodium
• Phylum Ciliata


  Includes Paramecium, Vorticella
• Plasmodium causes malaria, an infectious disease
• Plasmodium Life Cycle


  Spends time in human liver and red blood cells, transmitted by mosquitoes
• Plasmodium Reproduction


  Sexual reproduction involves fusion of macrogametes (female) and microgametes (male)
• Infected red blood cells show "signet-ring" appearance or dark spots
• Paramecium


  • Protected by a pellicle
  • Asymmetrical due to an oral groove on the ventral side
  • Contains a macronucleus, micronucleus, and contractile vacuoles for osmoregulation
• Vorticella


  • Resembles an inverted blood and is attached by a contractile stalk
  • Contains a bean-shaped macronucleus, a dot-like micronucleus, and food vacuoles
• Phylum Porifera


  • Pore-bearing sac-like bodies dependent on water currents
  • Cells embedded in a gelatinous matrix with spicules of calcium carbonate or silica
  • Asconoids, Syconoids, Leuconoids canal systems
  • Taxonomy based on the details of their endoskeleton (internal skeleton)
• Classes in Phylum Porifera

  • Calcarea: Grantia, Leucosolenia
  • Hexactinellida: Euplectella (Osculum is large and covered by sieve plate)
  • Demospongiae: Spongia, Carteriospongia, Astrosclera
• Phylum Cnidaria


  • Radially symmetrical with oral end having a mouth surrounded by tentacles
  • Epidermis, gastrodermis, and mesoglea layers
  • Polyp form and Medusa form for different species
  • Specialized stinging cells called cnidocytes with nematocysts for prey capture
• Classes in Phylum Cnidaria

  • Hydrozoa: Hydra, Obelia
  • Scyphozoa: Aurelia
  • Cubozoa: Chironex
  • Anthozoa: Scleractinia (Acropora, Fungia), Actiniaria (Metridium), Antipatharia (Antipathes), Alcyonacea (Tubipora, Sarcophyton)
• Hydra


  • Solitary polyp without a medusa phase, mouth located on a conical elevation called the hypostome surrounded by tentacles, asexual reproduction through hollow outgrowths called buds
• Obelia Life Cycle


  Includes both polyp and medusa stages, main stem is called hydrocaulus attached to the substratum through hydrorhizae, side branches give rise to nutritive hydranths or gastrozooids, mature colonies bear reproductive polyps and gonangia or gonozooids, gonangia contain young medusa buds, transparent chitinous layer, perisarc, covers the colony, young medusa buds stacked on top of each other
• Aurelia


  • Semi-transparent umbrella shape, short tentacles with nematocysts, square mouth opens at the end of the manubrium, manubrium extends into four oral arms for prey capture
• Metridium


  • Flattened oral disk with short tentacles, mouth leads to pharynx and gastrovascular cavity, siphonoglyphs drive water circulation, pedal disk attaches the animal to a substrate
• Acropora


  • Staghorn corals with plate-like colonies, nonliving exoskeleton of calcium carbonate, individual coral polyps encased in corallite, polyps interconnected laterally