Arthropoda NOTES April 02, 2012

Invertebrate Animals: ArthropodsDomain: Eukaryota

Kingdom: AnimaliaPhylum: Arthropoda

Arthro = jointed Poda = feet

Marine examples:

Other Examples?

PHYLUM CHARACTERISTICS:

** Largest phylum in the Kingdom Animalia with over 1 million species. (3 out 4 animals on Earth are arthropods).

**Taxonomists estimate that there might be 10 million arthropods on Earth.

*Symmetry?

Arthropoda NOTES April 02, 2012

3 Major Characteristics of arthropods:

1. JOINTED APPENDAGES (legs, mouth parts, antennae)function: movement, grab prey, injecting poison

*Because the exoskeleton does not grow, arthropods must molt.

Define Molt

2. EXOSKELETON (made of chitin + waxy outer layer)function: armor-like protection. muscles attached.

Disadvantages?

Arthropoda NOTES April 02, 2012

3. SEGMENTED BODY (usually 2 or 3 major segments)

Five major classes in the Phylum Arthropoda:Class Diplopoda

ex. millipedes

Class Chilopoda ex. centipedes

Class Crustacea- the majority of marine arthropods.Examples:

Class Insecta—the majority of terrestrial arthropods.Ex. butterfly, beetles, wasp, mosquito, fly

***Most species in this class.

Class ArachnidaEx. horseshoe crab, spider, scorpion

Arthropoda NOTES April 02, 2012

Crustacean Characteristics:

*Planktonic larval stage

*Open circulatory system

*Well developed nervous system

*Compound eyes (many lenses)- See multiple images.

Good for sensing slight movements

*Separate sexes (most crustaceans)