1. Characteristics of Vertebrates
All vertebrates have a backbone— a series of structures that surround and protect the nerve cord, or spinal cord.
The spinal cord connects all the nerves in the body to the brain.
Bones that form a backbone are called vertebrae.
Lesson 3-2

2. Characteristics of Vertebrates (cont.)
Vertebrates have well-developed organ systems.
All vertebrates have digestive systems with 2 openings, closed circulatory systems that move blood through the body, and nervous systems that include brains.
The five major groups of vertebrates are fish, amphibians, reptiles, birds, and mammals.
Lesson 3-2

3. Fish
Fish spend their entire lives in water and have two important characteristics in common: gills for absorbing oxygen gas from water and paired fins for swimming.
Lesson 3-3

4. Fish (cont.)
Hagfish and lampreys lack jaws and are in a group called jawless fish.
Lesson 3-3

5. Fish (cont.)
Sharks, skates, and rays are cartilaginous fish with skeletons made of a tough, fibrous tissue called cartilage.
Lesson 3-3

6. Store oil in liver to stay afloat
Cartilaginous Fish
Store oil in liver to stay afloat
Still denser than water and need to keep moving to stay afloat
Some must swim to maintain the flow of water over their gills
If they stop swimming, they will suffocate
Others do not have to swim
They can lie on the ocean floor and pump water across their gills

7. Fish (cont.)
Trout, guppies, perch, tuna, mackerel, and thousands of other species do not have cartilaginous skeletons. They have bones and are grouped together as bony fish.
Lesson 3-3

8. Amphibians Frogs, toads, and salamanders belong to the class Amphibia.
Most amphibians spend part of their lives in water and part on land.
amphibian
from Greek amphi–, means “of both kinds” and bios, means “life”
Lesson 3-4

9. Young amphibians live in water and have gills and fins
Young amphibians live in water and have gills and fins. Through metamorphosis, most adults develop lungs and limbs and live on land, near water.
Lesson 3-4

10. Amphibians (cont.)
Lay eggs in water. These eggs do not have hard protective coverings, or shells.
No scales
Skin is thin, smooth, and moist
Don’t drink water
Absorb it through their skin
Lesson 3-4

11. Reptiles
Lizards, snakes, turtles, crocodiles, and alligators belong to the class Reptilia.
Lesson 3-5

12. Reptiles (cont.)
All reptiles have waterproof skin that is covered in scales.
Lesson 3-5

13. Reptiles (cont.)
Like amphibians, most reptiles have three-chambered hearts.
Lesson 3-5

14. Reptiles (cont.)
Unlike amphibians, lizards and other reptiles have lungs throughout their lives.
Most reptiles lay fluid-filled eggs with leathery shells that they lay on land.
Lesson 3-5

15. Endothermic: Warmblooded
(Birds and Mammals)
Warm blooded
(Endotherms)

16. Birds All birds are in the class Aves.
Birds have lightweight bones, skin covered with feathers and scales, two legs, and two wings.
Lesson 3-6

17. Birds (cont.)
Many birds can fly, and they have stiff feathers that enable them to move through the air.

18. Birds (cont.)
Birds have toothless beaks and digestive systems that include gizzards, organs that help grind food into smaller pieces.
Lesson 3-6

19. Birds (cont.)
Birds lay fluid-filled eggs with hard shells and feed and care for their young.

20. Birds (cont.)
Birds have many characteristics in common with reptiles and are thought to be descendants of dinosaurs

21. Share some characteristics with reptiles Vertebrates
BIRDS
Share some characteristics with reptiles
Vertebrates
Legs and feet covered by thick, dry scales
Skin around beak is scaly
Amniotic egg
BIRDS

22. Birds have many Adaptations for flight
High metabolism to get energy to fly
Eat large amounts of food in proportion to body weight
Large eyes
Air sacs – increase amount of oxygen taken in
Rapid heart rate - muscles get more oxygen from blood
Hollow bones
Powerful flight muscles attached to a keel

23. Mammals
Dogs, cats, goats, rats, seals, whales, and humans are among the many vertebrates belonging to the class Mammalia.
All mammals have hair or fur covering their bodies.
Mammals tear and chew their food using teeth.
Lesson 3-6

24. Mammals (cont.)
The most notable characteristic of mammals is the presence of mammary glands that produce milk which feeds young mammals.
Mammals are grouped according to how their young develop.
Lesson 3-6

25. Develop inside mother’s uterus
Attached to mom by a placenta-an organ that transfers oxygen, nutrients and waste
Give birth to completely developed live young
Placental Mammals

26. Monotremes- mammals that lay eggs
Just 2 species alive today
Echidna
Spine-covered with long snouts
Long sticky tongue for catching ants & termites
Platypus
Swimming mammal
Lives and feeds in rivers and ponds
Webbed feet, flat tail, flat, rubbery bill to dig for food and to dig long tunnels to lay eggs

27. Marsupials Mammals with a pouch Give birth to live young
Shortly after birth- drag themselves through mother’s fur until they reach a pouch in her abdomen
Mammary glands are located inside pouch

28. Marsupials cont’
Young Kangaroos (Joey) climbs in, latches onto a nipple, and drinks milk