Cheatography
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Chap 33-34-Animal Diversity Part 2
Vertebrae, the series of bones that make up the vertebral column, or backbone.
This is a draft cheat sheet. It is a work in progress and is not finished yet.
Deuterostomia
radial cleavage (embryonic stage) |
triploblastic (3 germ layers: endoderm, mesoderm, ectoderm) |
bilateral larvae – adults are Pentaradial (lose bilateral symmetry) |
Madreporite - opening for water vascular system |
clade: Amniota
(1) Amniotic egg (w/ 4 extraembryonic membranes) |
Chorion- protect, help from placenta (in mammals), gas exchange |
Allantois - disposal sac, help from umbilical cord, gas exchange |
Yolk sac - nutrition (in reptiles), form blood vessels (in mammals) |
Amnion- membrane closest to the embryo, forms fluid-filled sac, shock absorber |
(2) Impermeable skin |
(3) Rib cage - ventilate lungs |
Clade: Lepidosaurs
earliest reptiles |
1. scales w/ keratin |
2. shelled amniotic eggs laid on land |
3. internal fertilization (inside female) |
4. many ectothermic; birds are endothermic |
2 pair appendages |
snakes & lizards |
Archosaurs
large opening (snout) |
crocodiles, pterosaurs, dinosaurs |
Crocodilia - crocodile = narrow snout; alligator= broad, wide snout |
Pterosaurs - wings of collagen |
Dinosaurs - 2 lineages by hip structure: |
- Ornithischian - "bird-hipped" ; herbivores; did not evolve in to birds |
- Saurischian - "lizard-hipped"; retained ancestral hip; long-necked ; theropods; evolved into birds |
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Chordata
bilateral symmetry |
coeloms and segmented bodies |
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Derived Characteristics of Chordates: |
- dorsal, hollow nerve cord |
- notochord from mesoderm; support |
- pharyngeal slits - all chordate embryos; grooves become slits that open into pharynx |
- post anal tail - movement; reduced in embryology |
Gnathostomata
jaws , fins (maneuvering), gills (gas exchange) |
enlarged brains, enhanced senses |
genetic duplication (hox genes) |
lateral system (aquatic) - sensitive to vibration |
Jaws- major adaptation ; modified skeletal rods |
Ancestral Amniote
Diapsids |
Synapsids |
Skull = 2 hole either side |
Skull = 1 hole either side(Temporal Fenestra) |
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mammals |
Bird Origin
archosaurs |
evolved from theropods |
Archaeopteryx- oldest bird |
digit loss/fusion = wing-joint flight |
loss of teeth |
wing claw lost |
hollow bone= reduce weight |
long tail w/ vertebrae |
reduction in growth rate in juveniles |
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Vertabrata
complex nervous systems & behaviors |
backbone or Rudimentary Vertebrae - endoskeleton |
2 or more sets Hox genes (genetic complexity) |
Pharyngeal Cleft/Groove |
Neural crest cells disperse thru embryo (teeth, skull, neurons) |
Cyclostomata - circular mouth, no jaws |
3 lineages of Gnathostomata
Chondrichthyes |
cartilage skeleton |
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calcium mineralization |
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suspension feeders; shark-teeth |
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Cloaca - reproductive tract |
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Shark & Rays |
Osteichthyes (Actinopterygii) |
bony endoskeleton and scales |
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tetrapods |
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swim bladder |
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gills |
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lateral line system |
Tetrapods (Sarcopterygii) |
4 limbs |
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ears |
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head on necks that move independently from body |
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pelvic bones |
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absence of gills |
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has clade: Amniota |
Amphibians |
water and terrestrial environments (damp habitats) |
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moist skin |
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eggs w/o shell |
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external fertilization |
Actinopterygii & Sarcopterygii:
- operculum (gill cover)
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