1. Phylum Chordata Continued Chapter 11
The Vertebrates
Phylum Chordata Continued
Chapter 11

2. Vertebrate Characteristics
They are chordates, so they have what 4 characteristics?
Plus – vertebrates also
have a backbone of vertebrae

3. What vertebrates include and some of the distinguishing characteristics

4. According to this figure, lobe-finned fish are excluded from the tetrapods because they lack which of the following characters?
A) vertebral column D) lobed appendages
B) jaws E) legs with multiple digits
C) lungs or lung derivatives

5. 3 tissues, true coelom – same as seen in invertebrates
Gill slits only seen in embryo
Most primitive are considered the jawless fishes: hagfish and lampreys
Hagfish have head, but no vertebrae – still only supported by a notochord
40 spp of hagfish – scavengers on ocean bottom; slime = defense, skin used to make fake eel skin belts & purses

6. What trait is shared by all animals?
Generate carbon-based molecules by photosynthesis
Heterotrophic – eat other organisms as a source of energy and carbon
They are motile through all stages of their life
They have vertebrae
They have three embryonic tissues that give rise to all of the organ systems and body wall.
Check question

7. Fishes Jawed – hinged for biting and chewing
Some have cartilage skeleton
Some have boney skeleton
Cartilage fish must swim to stay up in open water and to move water over their gills. Boney fish swim bladder = develops into a lung in lobed fin fishes used to gulp air in shallows to augment oxygen from gills.

8. Fishes (con’t) Ray-finned Fishes Lobe-finned Fishes
Fins have rays – for more flexible movement
Swim bladder provides buoyancy
Operculum – protective cover over gills, creates flow of water over gills without swimming being necessary
Lobe-finned Fishes
Fins have rod-shaped bones in two sets of paired fins
Fins allow for “walking” on bottom
Common in fossils, some living
forms like Lungfish
Gave rise to terrestrial vertebrates
Coelacanth; During Devonian (400 mya), lots of swamps with temporary pools of water. Fish would walk between ponds on fins and gulp air into sacs for oxygen while out of water.

9. The first vertebrate with a head and skull probably resembled a
A) lobe-finned fish.
B) lancelet.
C) hagfish.
D) lamprey.
E) shark.

11. First show up in fossil record about 375 mya
Breathe by pair of small lungs, also across skin
Skin is thin, can dry out, so need to stay in moist areas (also need wet surface for gas exchange)

12. Transition water to land

13. Reptiles Snakes, lizards, alligators, turtles, dinosaurs, crocodiles
Birds evolved from reptiles and your book includes them as reptiles

14. Amniotic Egg
Leathery in reptiles (not birds)

15. Birds
Many dinosaur features, including walking on hind legs and modified front limbs
Egg shell different from that of lizards

16. Advantages of Flight
Seasonal movements, finding food and nest material, avoiding predators, etc.

17. Cuticle seals plant surfaces and helps plants conserve water and the seed helps derived plant groups to reproduce effectively on dry land. The analogous adaptations in reptiles are ________ (analogous to cuticle) and ________ (analogous to the seed).
A) scales jellylike egg masses
B) scales the amniotic egg
C) scales aquatic larvae
D) claws lungs
E) moist skin jellylike egg masses

18. Mammals Terrestrial, secondarily aquatic Three major groups:
Monotremes – egg laying
Marsupials
Placental mammals
Whales, dolphins, etc.

20. Monotremes Duckbilled platypus, spiny anteaters (echidnas)
Evidence that mammals evolved from reptiles just like birds
Very few species

21. Marsupials
Kangaroos, wallabies, opossum, koala, squirrel gliders, Tasmanian tiger (extinct)
Young born very small

22. Placental Mammals
Young develop inside female, where kept hydrated without the egg
Internal development in female uterus = protection from predators and other ways eggs can be damaged
Placenta makes internal
development possible
Mammary glands used to feed
young

23. What vertebrates include and some of the distinguishing characteristics

24. Transition from moist to terrestrial environment -what problems needed solving?
Protection of outer body – prevent desiccation
Respiratory surface that remains wet (required for gas exchange of O2 and CO2)
Animals, plants and fungi

25. Transition from moist to terrestrial environment -what problems needed solving?
Reproduction – sperm need to reach egg without drying out
Sperm is transferred in packets
Direct transfer into female track using appendage
Protect young from desiccation during development
Egg
Internal development
Oceans – sperm released into water; Other? - plants we’ll see

29. Activity

30. Read chapter 12 Plant and Fungi Diversification