Arthropoda (Arthropods)
Arthropods have a segmented body, a tough exoskeleton, and jointed appendages.
Body Plan:
Arthropods have an exoskeleton, it is made of protein and chitin. Arthropods also have jointed appendages. Circulation:
Arthropods have an open circulatory system. Heart pumps blood through arteries. Blood leaves blood vessels and moves through sinuses, The blood collects in a large sinus around the heart then enters the heart and then the process is repeated. Response:
Most arthropods have a well-developed nervous system and brain. Along the nerve cords are several ganglia that coordinate movements of legs and wings. Most arthropods have sophisticated sense organs, like compound eyes that have more than 2000 separate lenses. |
Feeding:
Arthropods are herbivores, carnivores, and omnivores. Their mouth parts have evolved to enable different species to eat almost anything.
Excretion:
Reproduction:
Terrestrial arthropods have internal fertilization. Aquatic arthropods may have internal or external fertilization. |
Subphylums
Subphylum Crustacea:
-Have segmented bodies with hardened limbs -Two pairs of antennae -Two compound eyes -Body with 7 or more pairs of sometimes very different appendges for feeding, motion and sex -Respiration by gills -Nauplius- larval stage with 3 pairs of branched appendages -Orginially aquatic, many have adapted to life on land Subphylum Hexapoda:
-Outnumber all other plants and animal groups -Found in all environments -can fly up to 10,000 ft. high -Three body divisions Head Thorax Abdomen -Exoskeleton Subphylum Chelicerta:
-Spiders, mites/ticks, scorpions -Cephalothorax (Head fused to thorax) and abdomen Subphylum Trilobitomorpha: -abundant more than 500 million years ago -many body segments -each with a walking leg -became extinct 200 million years ago Subphylum Myriapoda -Millipedes and centipedes - over 13,000 species -all terrestrial |