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SCIENCE 6.
UNIT 4. INVERTEBRATES.
CONTENTS: 1.- Characteristics of animals and classification: Invertebrates– vertebrates. 2.– Invertebrates: characteristics. 3.- Classification: 3.1.– Sponges: sponge 3.2.– Cnidarian: jellyfish, coral 3.3.– Echinoderms: starfish 3.4.– Worms: A.– Annelids: earthworm B.– Plathelminthes (flatworms): taenia C.– Nematode: (roundworms): pinworm 3.5.– Mollusks: A.– Gastropods: snail B.– Bivalves: clam C.– Cephalopods: squid 3.6.– Arthropods: A.– Insects: wasp B.– Arachnids: spider C.- Crustaceans: prawn D.– Myriapods: scolopendra
C.E.I.P. SANTA ANA (Madridejos)
ANIMALS are multicellular and consumers. Most of them have sexual reproduction and can move.
1 There is a great variety of animals.
1.– CHARACTERISTICS OF ANIMALS & CLASSIFICATION: We can find a great variety of living beings in the animal kingdom, but they have some common characteristics like: 1.- All of them are multicellular, with tissues, organs.... 2.- All of them are consumers. 3.– Most of them have sexual reproduction. 4.- Most of them can move.
There are two main groups: invertebrates and vertebrates. A.- Invertebrates: animals without a backbone (spinal column), although some of them have a protection system like shells, or jointed plates. B.- Vertebrates: animals with a backbone. They have an internal skeleton formed by bones and a spinal column. Their body is divided in head, trunk and limbs.
ANIMALS can be:
2.– INVERTEBRATES: CHARACTERISTICS. .– Invertebrates: without a backbone. Most of animal species are invertebrates, about 97%. .– Vertebrates: with a backbone. Invertebrates have some common characteristics: 1.- They don’t have a skeleton or backbone. 3 2 2.– They are heterotroph (consumers) 3.– Most of them have a digestive cavity with one or two openings 4.- Some of them have their body protected by shells, jointed plates, hard skin…
Coral and anemones are invertebrates.
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USEFUL WORDS: .– multicellular .– consumer/heterotroph .– invertebrates .- vertebrates .– backbone / spinal column