Invertebrates

Key characteristics of Animalia (Invertebrates)

1. Segmented bodies

2. Multicellular

3. No spinal column

4. Eukaryotic

5. Motile Living Things

6. Cannot synthesize food

7. Mode of nutrition is by ingesting food

Example :

Phylum Cnidaria:

Sea anemones, Corals, and Jellyfish

Characteristics

- Radially Symmetrical

- Two different forms exist, medusa and polyp

Phylum Annelida:

Segmented worms

Characteristics

- Body possesses 3 separate sections, a prosomium, a trunk and a pygidium

- Reproduction normally sexual and gonochoristic or hermaphroditic.

Phylum Mollusca:

Clams, Snails, and Squids

Characteristics

- Has an open circulatory system with a heart and an aorta

- Has a nervous system with a circum-oesophagal ring, ganglia and paired nerve chords

Phylum Arthropoda:

Lobsters, Beetles, Crabs, and Flies and Scorpions

Characteristics

- Body possesses 3 to 400+ pairs of jointed legs

- The exoskeleton may also have some composition of lipids, other proteins, and calcium carbonate

Phylum Echinodermata:

Sea urchins, Sea cucumbers, and Starfish

Characteristics

- All echinoderms are marine organisms

- Water vascular system

http://www.msc.ucla.edu/oceanglobe/pdf/Invertebrates/Inverts_Entire.pdf

http://www.earthlife.net/inverts/mollusca.html

http://www.earthlife.net/inverts/cnidaria.html

http://www.earthlife.net/inverts/annelida.html

http://tolweb.org/Echinodermata

http://library.thinkquest.org/28751/review/animals/7.html

http://wiki.answers.com/Q/What_are_characteristics_of_organisms_belonging_to_the_phylum_arthropoda

http://www.earhlife.net/inverts/arthropoda.html

http://www.oum.ox.ac.uk/thezone/fossils/inverts/images/wheel1.gif

Done by Choi Min Suk, Goh Jun Hong and Chan Jun Wei