Classifying Animals Chapter 1 Lesson 3

What are simple invertebrates Animals that do not have a backbone They can live on land and in the water

Sponges They do not have true organizations They are the only animals without real tissues or organs They are members of the phylum Porifera. All members of this phylume live in water

Cnidarians Jellyfish, sea anemones, corals, and hydras Soft-bodied, aquatic creatures Radial symmetry, tentacles, muscle tissues, stinger cells, and a mouth

Worms Three main worms: flatworms, roundworms, and segmented worms Have bilateral symmetry

What are complex invertebrates? Echinoderms Mollusks Have muscular foot or tentacles, a fold of tissue, and a mass of internal organs Squids, snails, clams, octopus Almost all have a shell Gills for breathing, heart, and well-developed nervous system Sea stars, sea urchins, sea cucumbers Have a skeleton located inside the body called endoskeleton. Have many tube feet that cling like suction cups

Arthropods Most numerous animal group of Earth with more than half of the world’s animal species included Spiders, crabs, and insects They are small and light with a hard skeleton on the outside of the body called an exoskeleton. This provides strength and protection

Arthropod Echinoderm Mollusks

What are vertebrates? Fish Fish are cold-blooded Fish have gills that allow them to breathe under water There are 3 classes of fish: jawless, cartilaginous fish, and bony fish

Amphibians Frogs, toads, and salamanders Cold-blooded They bridge the gap between land and water vertebrates because they spend part of their lives in the water and part on land (frogs) They have gills but develop into lungs

Reptiles True land animals with one or two lungs Thick, scaly, waterproof skin Lizards, snakes, turtles, alligators, and crocodiles Cold-blooded. They stay warm by sunning themselves

Birds Have two legs, and two wings FEATHERS- these are specific to birds Feathers keep heat inside the birds’ bodies Birds are warm-blooded and maintain a constant temperature

Mammals Milk, hair, and large brains are key characteristics Monotremes are mammals that lay eggs: duck-billed platypus & anteater Marsupials are pouched mammals that give birth to partially developed offspring: kangaroos and koala bears Placental mammals develop within its mother Whales, dolphins, humans, dogs, elephants, tigers Milk, hair, and large brains are key characteristics They produce milk to feed their young All mammals have hair or fur Mammals are warm-blooded