InvertebratesInvertebrates

1. Invertebrates have no ______________

2. They make up ______% of the animal kingdom.

3. There are ______ groups

3. They are _________cellular.

4. Their nutrition is __________.

5. Their reproduction is _________.

What will talk about in the next weeks?1. What are the different groups of invertebrates?

2. What are the characteristics of these groupsnutritionreproductionhabitatscientific name

3. Evaluation: At the end we will have an exam

Group 1 Sponge

Scientific name: Porifera

A Sponge never moves. It stays in the same place all its life.

It reproduces sexually. The male and female release the sperm and ova into the

water to make a new sponge.

It lives in salt-water, in the seas and oceans all around the world.

How does it feed?Look at the diagram.

Water moves through

the holes. The

sponge takes the

nutrients and then

the water leaves the

sponge.

http://www.youtube.com/watch?v=T7E1rq7zHLc

Group 2: Coral, hydras and jellyfish

Scientific name: Cnidaria

What do they all have in common?1. They all can sting, and the jellyfish is sometimes toxic to humans

2. They hunt their food. They catch it in their tentacles and then eat

it.

3. The have one hole that serves as a mouth and anus!

What are the differences?Hydra and coral do not move, jellyfish can move.

Hydra have asexual reproduction-budding

Jellyfish and coral use sexual reproduction

Jellyfish and Coral live in warm seas, hydras live in ponds

JellyfishTentaclesTentacles

One hole-mouth and anusOne hole-mouth and anus

Group 3 Worms-divided into

three

Group 3a Segmented worms

Scientific name : AnnelidThese worms' bodies are formed of ring like segments-earthworm

They are hermaphrodites-they can be both male and female

They have a head and a tail, and their body is moist to help movement

They eat decaying plants and animals.

They live in the ground

Why are they important?

SegmentsSegments

HeaHea

dd

TailTail

Group 3b Round worms

Scientific name: Nematoda

These worms cannot move very well

They taper to the end

They reproduce sexually

All in the pictures are parasites, they live in other plants or animals,

including humans

Parasite

A worm A worm

living in living in

someones someones

eyeeye

This is a tape worm. It was This is a tape worm. It was

living in a cow's intestineliving in a cow's intestine

Group 3c Flat worm

Scientific name: Plathhelminthes

These are the most primitive of the worms

They reproduce sexually

Most have a mouth but no anus!

Most of this group are parasites.

This is a liver This is a liver

fluke. They fluke. They

are very are very

dangerous to dangerous to

farm animalsfarm animals

These worms live in the seaThese worms live in the sea

Group 4 Sea Urchin and Star Fish Scientific name: Echinoderms

These animals are fixed or they move very slowly. They have spines to protect themselves.They lived in salty water. They do not have a head, and the mouth is on the underside.They are carnivorous and eat small crustanceans or molluscs. The reproduce sexually, by eggs and some species are hermaphrodite.

Mouth on Mouth on undersideunderside

Spines for Spines for protectionprotection

Starfish eating

Army of Sea Urchins -

From one leg, a star fish From one leg, a star fish can regenerate his can regenerate his whole body!whole body!

Group 5 Molluscs

Every mollusc has these similarities:

A head-it contains head and eyes and mouth

A body with all the main organs

A foot which helps them move about

They can be carnivores or herbivores

They reproduce sexually, with eggs. They are also hermaphrodite.

Most have a shell of one or two valves

Head and eyesHead and eyes

ShellShell

FootFoot

There are three groups.

1.1. GastropodsGastropods-slugs, snails and sea snails. They have a shell, except the ______

2.2. BivalvesBivalves-clams, cockles, mussels. Their shell has two valves.

3.3. CephalopodsCephalopods-squid, cuttlefish and octopi. They have tentacles, but no_______

Shark vs. Octopus

Quagga Mussels Feeding

giant slug eats flower

Group 6: Arthropods

Scientific name: Arthropods

What do they have in common?

Their segmented body is divided into three parts-head, thorax and abdomen.

They all have antennae on their head

They reproduce sexually by eggs.

They moult-this means their old skin falls off and they then grow a new one.

Each group has its own characteristics

How many groups are there?

Group Examples Body Habitat

Crustanceans legs

Myriapods centepede worm-like, many legs

Anrachnids legs

Insects legs, antennae2 or 4 or no wings

Some videos on Arthropods

YouTube - A Huge Centipede Fighting A Snake YouTube - BIG spider - tarantula on my hand