Arthropoda
Arthropoda is the largest of all the phylum's and includes well over one million species. Even though there is a huge variety of arthropods, they all share similar aspects of a body. Some of the similar characteristics are:
- A hard exoskeleton composed mainly of chitin.
- Appendages with joints. The word "arthropod" means "jointed feet".
- Some arthropods have highly developed sense organs.
- Arthropods have an open circulatory system.
- Arthropods also have a complete gut with two openings, the mouth and the anus.
- Fertilization usually occurs internally, and most species are egg laying.
- A hard exoskeleton composed mainly of chitin.
- Appendages with joints. The word "arthropod" means "jointed feet".
- Some arthropods have highly developed sense organs.
- Arthropods have an open circulatory system.
- Arthropods also have a complete gut with two openings, the mouth and the anus.
- Fertilization usually occurs internally, and most species are egg laying.