Phylum Chordata

Phylum ChordataIncludes 5 Classes1.Fish2.Amphibians3.Reptiles4.Birds5.Mammals

Fish• Habitat: nearly every

aquatic environment• Respiration: use gills to

breathe• Circulation: 2 chambered

heart• Reproduction: sexual

(mostly external)• Nervous System: lateral line

system that can detect movement

Fish• 3 Major Types of Fish

• Jawless Fish• Cartilaginous Fish (chondricthes)• Bony Fish (osteicthes)

Amphibians• Examples: frogs, salamanders, toads• Habitat: live on land and water• Respiration: lungs in adults, gills in tadpoles, but

mostly through the moist skin• Reproduction: External reproduction (water needed to transport sperm and eggs must be kept moist)

Amphibians• Circulation: 3

chambered heart (mixing)

• One chamber gets oxygen-rich blood from the lungs and skin

• One gets oxygen-poor blood form the rest of the body

• Both of those chambers collect in a third chamber that pumps a mix of oxygen-rich and oxygen-poor blood to the lungs, skin and body

Amphibians• Temperature Regulation:

Ectotherms, variable body temperature – gets heat from outside source

• Metamorphosis – eggs, tadpoles, adult• Tadpoles – fins, gills, 2-

chambered heart• Adult – legs, lungs, 3-

chambered heart

Reptiles• Examples: snakes, crocodiles,

turtle, lizards• Habitat: Land mostly• Respiration: No exchange thru

skin bc it is scaly MUST use lungs

• Circulation: most have 3 chambered heart

• Obtain food: claws, legs directly under body makes running easier

• Temp Regulation: ectotherms

Reptiles• Reproduction:

Internal fertilization and can lay eggs on land due to the evolution of the amniotic egg

Amniotic Egg• Amnion: fluid that cushions

embryo• Shell: leathery shell• Yolk: food source for

embryo• Allantois: wastes are

excreted into this• Chorion: allows gas

exchange• Egg tooth: horny tooth that

helps hatch the egg

Birds• Examples: pelican, penguin, blue jay • Respiration: lungs and air sacs for

extra oxygen for flight• Temp Regulation: Endotherm

(internally regulates body temp so it is constant)

• Reproduction: internal fertilization and lay amniotic egg with a hard shell, must incubate eggs

• Characteristics to Fly: hollow bones for flight, feathers are lightweight, wings, one urogenital orphus

Birds• Circulation: 4 chambered heart (one side pumps oxygen-poor blood

to lungs the other side pumps oxygen-rich blood to the rest of the body)

MammalsMust haves to be a mammal: Hair Mammary glands that secrete

milk to nurse young Diaphragm to expand and

contract chest cavity to get more oxygen

Specialized teeth (ex. Molars, canines, incisors)

Can learn!

Mammals • Temp Regulation: Endotherms, maintain fairly constant body temperature

• Circulation: 4 chambered heart the oxygenated blood is kept separate from the deoxygenated blood

• Respiration: Diaphragm – sheet of muscle located beneath the lungs that separates the chest cavity from the abdominal cavity

Mammals• Why is HAIR important?

• Insulation• Waterproofing• Conserves body heat

• Mammals cool off by panting and sweating

Mammals

Mammals are classified into 3 groups based on their method of reproduction

1. Placental Mammals2. Marsupials3. Monotremes

Placental Mammals• Carries baby in the mother’s

uterus until development is almost complete

• Placenta provides food for the baby, allows gas exchange, and removes waste

• 95% of mammals are placental

Marsupials• After a baby has grown

to a certain size, the mom carries the baby inside a pouch made of skin and hair on the outside of the mom’s body

• Most are found in Australia

Monotremes• Reproduces by laying eggs• Found only in Australia,

Tasmania, and New Guinea

• 3 species of monotremes alive today (platypus, spiny anteater and long-beaked echidna