1. Phylum
    2. 1. Classification of Animals
    2. Protozoa
    3. Porifera
    4. Coelenterata
    5. Platyhelminthes
    6. Nemathelminthes
    7. Annelida
    8. Earthworm
    9. Arthropoda
    10. Cockroach
    11. Mosquito
    12. Honey bee and Silk moth
    13. Mollusca
    14. Echinodermata
    15. Hemichordata
    16. Chordata
    17. Pisces
    18. Amphibia
    19. Frog
    20. Reptile
    21. Aves
    22. Mammalia
    23. Rabbit bone
  2. Animal Behaviour and Adaptation
    3. 24. Animal behaviour
    25. Animal adaptation
    26. Migration
  3. Developmental Biology
    4. 27. Development of Animals
    28. Development of Frog
  4. Human Biology
    5. 29. Tissues
    30. Sense organs
    31. Digestive system
    32. Circulatory system
    33. Respiratory system
    34. Nervous system
    35. Endocrine system
    36. Reproductive system
    37. Excretory system
    38. Skeletal system
    39. Basic concept of Immunology
    40. Human diseases
  5. Evolutionary Biology
    6. 41. Origin of Life
    42. Organic Evolution
    43. Theories of Evolution
    44. Evolution of Human beings
    45. Horse Evolution
Phylum
17. Pisces
▢ Topic: General Characteristics of Fishes
▢ Details:
❖ 1. Ichthyology: The branch of zoology dealing with the study of fishes.
❖ 2. OrdovicianPeriod:
◉ Era: Palaeozoic
◉ Details: Fishes originated in the Ordovician period of the Palaeozoic era.
❖ 3. Ostracoderm:
◉ Description: Earliest known vertebrate fossils; jawless, bony-armored fishes.
❖ 4. BodyDivision:
◉ Parts:
  1. Head
  2. Trunk
  3. Tail
◉ Neck: Absent
❖ 5. Locomotion:
◉ FinsUsed:
  1. Paired pectoral fins
  2. Paired pelvic fins
  3. Median dorsal fin
  4. Caudal fin
❖ 6. TypesOfScales:
  1. Placoid
  2. Cycloid
  3. Ctenoid
❖ 7. Myotomes:
◉ Description: Muscles are arranged in segmental blocks called myotomes.
◉ MyotomeDefinition:
◈ General: Muscles served by a single spinal nerve root.
◈ Embryology: Part of somite that develops into muscles.
❖ 8. Heart:
◉ Chambers:
◈ Auricle: 1
◈ Ventricle: 1
◉ Type: Venous heart (pumps only deoxygenated blood)
◉ SinusVenosus: Present
◉ PortalSystems:
  1. Renal portal system
  2. Hepatic portal system
❖ 9. Kidneys:
◉ Type: Mesonephric
◉ Excretion:
  1. Ammonotelic
  2. Ureotelic
❖ 10. CranialNerves: 10 pairs
❖ 11. Ear:
◉ ExternalAndMiddleEar: Tympanum, tympanic cavity, and ear ossicles absent
◉ InternalEar: Contains 3 semicircular canals
❖ 12. LateralLineSystem: Lateral line receptors present for detecting vibrations and water currents.
❖ 13. Reproduction:
◉ Fertilization: Internal or external
◉ FemaleType:
  1. Oviparous
  2. Viviparous
◉ EggType: Macrolecithal (large eggs with much yolk)
◉ EmbryonicMembranes: Absent (Anamniotes)
◉ Development: Usually direct with little or no metamorphosis
❖ 14. Thermoregulation: Cold-blooded (Poikilothermic)
Category
Chondrichthyes / Cartilaginous fish
Osteichthyes / Bony fish
Type
Cartilaginous fish
Bony fish
Exoskeleton
Placoid scales
Cycloid or Ctenoid scales
Endoskeleton
Cartilages
Bone
Habitat
Marine fishes
  1. Both:
  2. i. Marine
  3. ii. Freshwater
Gill opening
Without operculum
With operculum
Mouth position
Ventral
Terminal
Characteristics
  1. a. Ampullae of Lorenzini: Chemoreceptor
  2. b. Maltese cross: Centrum with four cartilage
  3. c. Mermaid's purse: Shark egg capsule
  1. Possess Air bladder or Swim bladder:
  2. 1. Regulates Buoyancy
  3. 2. Acts as hydrostatic organ
  4. 3. Usually use lungs in gas exchange
Classes
  1. Elasmobranchii (Sharks, Skates, Rays)
  2. Holocephali (Chimaeras)
  1. Sarcopterygii (Lobe-finned fishes)
  2. Actinopterygii (Ray-finned fishes)
Examples (Sarcopterygii)
    1. 1. Neoceratodus (Australian lungfish)
    2. 2. Protopterus (African lungfish)
    3. 3. Lepidosiren (American lungfish)
    4. 4. Coelacanths:
    5. • Latimeria chalumnae – Caught off the coast of Africa
    6. • Latimeria menadoensis – Caught off the coast of Indonesia
    Examples (Actinopterygii)
      1. 1. Catfish
      2. 2. Flying fish – Exocoetus
      3. 3. Sea horse – Hippocampus
      Examples (Chondrichthyes)
      1. i. Great White Shark
      2. ii. Mako
      3. iii. Sting ray – Tail modified into defensive lash
      4. iv. Electric ray – Torpedo
      5. v. Rat fish – Chimaera
      6. vi. Scoliodon – Dog fish