ABS Exam 2 (2-chondrichthyes)

Card Set Information

Author:
djwon1
ID:
264827
Filename:
ABS Exam 2 (2-chondrichthyes)
Updated:
2014-03-03 03:00:20
Tags:
abs exam2 chondrichthyes
Folders:

Description:
abs 2
Show Answers:

Home > Flashcards > Print Preview

The flashcards below were created by user djwon1 on FreezingBlue Flashcards. What would you like to do?


  1. placoid scales?
    • dermal denticles
    • traces of bone are found
  2. Open-water swimmers have ___.
    oily livers
  3. function of Heterocercal tails
    lift
  4. Vertebral column (cartilage), replaces
    notochord
  5. First gill slit, remains open -
    spiracle
  6. Males have ___ (modified pelvic fin)
    claspers
  7. claspers?
    modified pelvic fin that male chondrichthyes have
  8. spiracle is ___
    function of spiracle?
    • vestigial gill
    • breathing
  9. spiracle is especially important for ___ chondrichthyes
    benthic
  10. Classification of Chondrichthyes
    • Holocephalans: (Chimaeras)
    • Elasmobranchs (Neoselachii)
  11. Holocephalans: (Chimaeras)
    • Single gill opening
    • Ratfish
  12. Elasmobranchs (Neoselachii)
    • Multiple gill openings (5-7)
    • Sharks, rays
  13. Elasmobranchs (Neoselachii)
    Pleurotremata (___ gill openings)
    • lateral
    • “Squaloid” sharks
    • “Galeoid” sharks
  14. Elasmobranchs (Neoselachii)
    Hypotremata (___ gill openings)
    • Ventral
    • Batoidea - skates and rays
  15. early radiation
    Stem chondrichtyes
    Cladoselache
  16. cladoselache characteristics
    • body support - notochord, cartilaginous neural arches
    • 2 dorsal, pectoral and pelvic fins
    • spines on anterior of 2 dorsal fins
    • few palacoid scales
    • caudal fin (symmetrical)
    • fins consist of 1 basal cartilage and long radials
  17. some early radiation - advances in ___ and ___ systems
    • feeding
    • locomotor
    • fins supported on 3 basal cartilages - rotation of fin
    • smaller radials - steering
    • caudal fin: reduction of hypochordal lobe, addition of flexible ceratortrichia
  18. heterocercal -
    • asymmetrical caudal fin
    • reduction of the lower lobe and addition of flexible ceratotrichia
  19. Main differences between earlier radiations and extant forms:
    • Snout that overhangs the ventrally-positioned mouth
    • Development of solid calcified vertebrae around notochord
    • Thicker and more complex enamel-like material on teeth
  20. Sharks, Skates, Rays appeared at least as early as the ___.
    Triassic (250 to 200 Ma)
  21. Differences Between Early and More Derived Sharks
    • Cartilaginous vertebral centra – axial skeleton canflex with rigid central elements of calcified cartilage
    • Placoid scales – single cusp and single pulp cavity
    • Unique body armor – reduces turbulence andincreases swimming efficiency
  22. Sensory Systems and Prey Detection
    • neuromast organs - lateral line systems
    • Ampullae of Lorenzini
    • Chemoreception
    • Vision: tapetum lucidum
    • Large brains
  23. Tapetum Lucidum
    • Reflects visible light, increasing light available to photoreceptors
    • Improves vision in low-light conditions
  24. Jaws and Feeding
    Cranial Kinesis
    mobility within the head skeleton - can consume large prey
  25. Jaws and Feeding
    extant sharks have ___ Jaw Suspension
    • Hyostylic
    • multiple jaw positions - different feeding opportunities
  26. exsanguination
    bleeding to death
  27. Reproduction
    • Internal fertilization
    • Pelvic claspers in males – enters cloaca; sperm ejected
    • Small male sharks wrap around female’s body
  28. Reproductive modes
    • oviparity
    • ovoviviparity
    • viviparity
  29. oviparity -
    baby hatches from egg
  30. Ovoviviparity
    • eggs retained in females body until ready to hatch
    • youngnourished by egg yolk, not placental connection
  31. Viviparity
    young nourished by placentalconnection; fully‐developed baby born
  32. Oviparous Chondrichthyes
    • Large eggs
    • Nidamental gland – secretes proteinaceous case around fertilized egg
    • Embryo – nourishment from yolk
    • Movement of embryo: flushes waste, brings in O2
    • Hatches as small adult
  33. Ovoviparous Chondrichthyes
    • Sexual maturity – 15 yrs of age
    • Eggs develop and hatch in uterus
    • 11-month gestation period
    • Intra-uterine cannibalism
  34. Viviparous Chondrichthyes
    • Retention of fertilized eggs in reproductive tracts
    • Eggs hatch within oviduct
    • some embryos feed on siblings and eggs (ex., Great Whites)
    • Young emerge as tiny adults
    • No parental care once sharks hatch
  35. Placentotrophic Matrotrophy
    form ofviviparity in which a yolk sac placenta develops that allows embryo to get nourishment from maternal uterine bloodstream via highly vascularized yolk sac
  36. Hypotremata - ventral gill openings
    • Bottom‐dwelling; spiracle behind eye
    • Dorsal‐ventral flattening of body
    • Lateral extension of pectoral fins – large surface area for Ampullae of Lorenzini
    • Teeth – for crushing prey
  37. Skates and Rays -
    Hypotremata
  38. Difference Between Skates and Rays:
    • Skates – tails broad & muscular with dorsal fins & terminal caudal fin, reproduction oviparous (eggs in leathery case)
    • Rays – tails thinner, “whip like”, no fins, sometimes dorsal barbs, reproduction viviparous
  39. Rays
    • Swim by undulating pectoral fins
    • Mostly benthic feeders – inverts, small fish
    • Largest rays are plankton‐feeders
    • Sexually dimorphic: body size (females larger) and dentition
  40. Holocephali – Chimaeras
    • rat fish
    • Long, tapered fin
    • Deep water
    • Upper jaws fused to braincase
    • Plates instead of teeth
    • Gills with operculum
    • Absent spiracle in adults
    • Pelvic clasper and Cephalic Clasper

What would you like to do?

Home > Flashcards > Print Preview