blog Invertebrates

Arachnids:They include Spiders, Scorpions, ticks, mites. Arachnids tend to have a hard exoskeleton and jointed appendages in order to support walking. Most of the Arachnids have 4 pairs of legs with equals to 8 total. They vary in size, while some surpass over 8 inches in length.  Some arachnids contain poison on their fangs, which excretes when bitten/stung to kill their prey. Spiders also have silk in order to produce egg sacks and catch prey as well. They have a hard body structure, many legs used for walking, and poisoness self defense mechanisms but they are also used for prey hunting


Insects:This group are considered one of the largest group of arthropods which contain about 800,000 different types. They have 3 body segments called the head, abdomen, and the thorax. Insects may have wings which enable them to fly while some do not simply need to fly. The wings are located on thorax. The thorax also consist of legs for walking or jumping.Insects have compound eyes for example, the fly has about 4000 lenses in a single eye. The insects hard exoskeleton makes them hard to grow to a bigger size and most insects molt in order to grow. Consist of 3 body segments, wings, and many eye lenses.molt=shedding of the out layer/skeleton

Annelids:Annelids consist of worms and leeches.  There are around 9000 known species that are found today. They have been on earth for over 120 million years and can be found at almost anywhere. Their body structure is divided into segments and have well developed internal organs. They are unique because they have no limbs. The most common type of Annelids are called earthworms, parasitic worms found in the human body like tapeworms, roundworms, and flatworms. They may also grow up to 100 ft in length. They do not contain the thorax, wings, or hard body structure like the other two.

http://www.kidport.com/reflib/science/animals/animalindexinv.htm
http://en.wikipedia.org/wiki/Invertebrate