invertebrates animals that do not have bones so they don’t have a skeleton or a backbone
TRANSCRIPT
INVERTEBRATES
Animals that do not have bonesSo
They don’t have a skeleton or a backbone
1.- Classification
Invertebrates are classified into smaller groups. Sponges Cnidarians Echinoderms Worms Molluscs Arthropods
SPONGES
They are the simplest type of animal that exits.
They cannot move.They attach themselves to rocks or the sea floor.
They are often irregular in shape.
Their bodies have lots of small holes that allow water to pass in and out.
They eat microscopic organisms in the water that they filter through their body.
CNIDARIANS
Cnidarians have jelly-fish like bodies.
They are aquatic animals. They have very simple bodies
with an opening at one end.This opening acts like a mouth and an anus.
They have soft tentacles that can sting you.
Some, such as coral and sea anemone, attach to rocks. Others, such as jellyfish, can move about.
Many cnidarians like jellyfish and sea anemones have a poisonous substance in their tentacles to catch their prey.
Jellyfish
Sea anemone
white coral
ECHINODERMS
Echinoderms are symetrical.
Starfish tipically have 5 or more arms which radiate from a central point where their mouth is.
Echinoderms are invertebrates with hard plates under their skin.Some like sea urchins have movable spines on the outside of their bodies.
They live in the bottom of the sea.
Starfish
Sea urchins
WORMS Worms are animals
with long, soft bodies and moist skin.
They do not have legs. They move by
wriggling. Most live in the sea or
in fresh water. Some live on land like earthworms.
Some worms are parasites. They live in the intestines of other animlas and eat their food.
MOLLUSCS
Molluscs are classified into 3 groups.
Gastropods.
Bibalves.
Cephalopods.
GASTROPODS
Gastropods usually have a shell where they hide in when they sense danger.
They move by sliding on a slimy, mucus substance that they excrete.
snail
BIVALVES
Bivalves have one shell divided into 2 moving parts called valves, which they close when they sense danger. They usually stay in one place.
They eat small organisms that are in the water. mussel clams oyster
CEPHALOPODS
Cephalopods have no protective external covering but some have a shell hidden under their skin.
All cephalopods are marine animals. They have eight or ten tenctalces that help them
to swim and catch teir prey.octopous squid cuttlefish
ARTHROPODS
Arthropods have an external skelenton called exoskeleton which supports and protects the body.
Classification:Crustaceans ArachnidsMyriapods Insects.
CRUSTACEANS
Most of them live in the sea. They usually have 10 legs The exoskeleton is very hard. lobster crab prawns
ARACHNIDS
Arachnids ar terrestrial and carnivorous.
Arachnids have 8 legs. spider scorpion
MYRIAPODS
Myriapods have many legs in their bodies.
centipedes millipedes
INSECTS
Insects have 6 legs.butterfly
Many insects have wings. Their body is divided into 3 parts:head, thorax
and abdomen.
fly mosquito grasshopper
bee wasp