1. BY:Juanje Ortega Lara

2. Invertebrates characteristics
 The main characteristics of invertebrates is that they
haven´t got a spinal column or an internal skeleton.
 Some invertebrates ,have got a hard shell to protect
themselves.
 Other invertebrates ,have got a rigid covering called an
exoskeleton.
 Some invertebrates ,have got a soft body without
protection.

3. Main groups of invertebrates.
 Mollusks
 Mollusks have got soft body ,but most of them have got
a hard shell too.

4. Jellyfish and Polyps
 They ´have got a soft body. Some of them have got long
tentacles .

5. Sponges
 They´have got a soft body whit holes called pores .

6. Annelids
 They ´have got a long, soft body that is divided into
rings called segments.

7. Arthropods
 They´have got an exoskeleton and jointed legs that
bend . They include insects ,spiders and crustaceans.

8. Echinoderms
 Their bodies are covered whit sharp spikes . Some
echinoderms have got arms and tentacles .

9. More arthropods
 Arthropods are the most numerous group of
invertebrates . Some invertebrates live in water ,other
invertebrates live on land . Many arthropods can also
fly.
 They ´have got an exoskeleton.
 Their bodies are divided into jointed parts.
 They ´have also jointed legs .

10. Insects
 Insects have got six legs . Their bodies have got three
main parts : the head , thorax and abdomen . Many
insects have got wings .

11. Arachnids
 Arachnids have got eight legs . Their bodies are
divided into two main parts ; the cephalothorax and
the abdomen.

12. Crustaceans
 Crustaceans have got ten legs . Their bodies are
divided into two main parts : the cephalothorax and
the abdomen .

13. Myriapods
 Myriapods have got many legs. Their bodies are
divided into two main parts : the head and the trunk.

14. More mollusks
 They ´have all got soft bodies .
 Most mollusks have got a hard shell and a thin layer
next to their shell called the mantle .

15. Mollusks
 Bivalves
 Bivalves have got a shell whit two parts , called valves .
 They´have got a soft body and no head.
 Bivalves are filter feeders . They filter water to extract
nutrients.

16. Mollusks
 Gastropods
 Many gastropods, have got a spiral shell . Other
gastropods ,haven´t got a shell.
 Gastropods have got a head and body . They ´have
also got four tentacles.
 Most gastropods are herbibores .

17. Mollusks
 Cephalopods
 Cephalopods have got a head whit a mouth and well-
developed eyes .
 They ´have also got long arms to catch their food.
Squid have got tentacles too.
 Most cephalopods are carnivores.