Exam 4.2 Flashcards
Vertebrata characteristics
Endoskeleton (cartilaginous–>bone)
Vertebral Column
More extensive nervous system
Paired appendages
Vertebral column
Derived from notochord
Surrounds and protects nerve cord
Vertebrata
Myxini
Hagfish
Jawless and no paired fins
Tongue embedded with teeth
Slime for protection
Petromyzontida
Lampreys
Jawless and no paired fins
Ectoparasite
Teeth embedded in sides of mouth
Gnathostomata
Jawed vertebrates
jaw is homologous with gill arches of jawless fish
Chondrichthyes and Teleostomi
Chondrichthyes
sharks, skates, rays, chimaeras
Cartilaginous skeleton
Placoid scales (pointing in the same direction to reduce drag)
Lateral Line System
Ampullae of Lorenzini (sense electrical fields)
Skates and Rays
Dorsoventrally flattened
Flat teeth for eating molluscs and crustaceans
Whiplike tail with venom gland in some
Chondrichthyes
Lateral Line System
senses vibrations in the water
Chondrichthyes
Ampullae of Lorenzini
sense electrical fields
Chondrichthyes
Teliostomi
Bony fish and tetrapods aka ray-fin fish and Sarcopterygii
Bone replaces cartilage
Swim bladder and lung
Actinopterygii
Ray finned fish
Oviparous
Fins are supported by long rays
Scales are ganoid or cycloid (ctenoid)
- Ganoid scales
2. Cycloid or Ctenoid scales
- older lineages
2. overlapping, lighter, flexible
2 groups of Sarcopterygii
lobed fin fish and tetrapods
Lobed fin fish
Ceolocanth and lungfishes
Paired, lobed fins with skeletal support
Preadapted for locomotion on land
2 groups of Tetrapoda
Amphibia and Amniota
- Eustenopteron
lobe finned fish, laterally compressed, no snout, dorsal fin
- Panderichthyes
lobe finned fish, dorso-ventrally compressed, snout, no dorsal fins
- Tiktaalik
“fishapod” long snout, WRIST and NECK
- Acanthostega and Ichtyostega
1st tetrapods, wrist and ankles, neck, DIGITS
Gymnophiona
Legless, fossorial, live in tropics
look like worms
Urodela
Salamanders
long tail with 4 legs in most (absent in aquatic ones)
Internal fertalization
Anura
Frog and toads
Sit and wait predators
Need water for some stage of life
Gills in larval stage and lost in metamorphosis
Toxins and chromatophores (cause bright colors)
Lepidosauria
Lizards and snakes
Vomeronasal organ (Jacobson’s organ)
well developed chemoreception
tongue flicks and brings molecules to the roof of mouth
Pit Organ
heat sensitive organ in pit vipers
Testudines
Turtle and tortoises!
External shell is connected to endoskeleton
Loss of teeth
All lay eggs on land and no parental care
Archosauria
Crocodilia and Aves Vocalization and displays Mom protects eggs/babies 4 chambered heart Unidirectional air flow Gizzard
Mammalia
Largest and most complex brain Endotherms 4 chambered heart Mammary glands Heterodonty (variation in teeth)
Monotremata
Oviparous
Spiny anteaters and Platypus
Mammalia groups
Monotremata
Marsupialia
Eutheria (placental mammals)