Arthropods, mollusks, echinoderms, Cnidarians
An arthropod is an animal that has a jointed exoskeleton
One kind of arthropods are lobsters, crabs,
exoskeleton covers and protects body and gives it support
digestive system with 2 openings
circulatory system and a brain
molts so exoskeleton can grow with animal
well developed organs for site, sound and touch
Lobsters - legs are adapted to catch prey and carry to mouth. Lobsters claws crush shells of oysters or clams and are 2 sizes for defense and tearing food.
Arachnids - many have sharp body parts that inject poison
Tarantulas - legs are evenly spaced for balance while walking and climbing
Grasshoppers - mouths are adapted for crushing food and back legs are powerful for jumping.
A mollusk is an animal with a soft body and no bones.
Example: clams, oysters, slugs, snails, squids and octopods
some have a hard shell that protects their body
Mantle - shell of mollusk, produces material to harden shell, grows as animal grows
some the mantle is a tough layer of skin
muscular foot - helps move and burrow into ocean floor
some have bivalves like oysters and clams
Radula - organ in snail that acts like a tongue with sharp teeth
octopus and squid have well developed brains and nervous systems
Adaptations - octopus and squid have jet like motion and squirt ink, snail has has a hard shell that protects itself.
Cnidarians have the ability to sting its prey, carnivorous animals, or meat-eating, poison in tentacles.
tentacles that sting its predators and bring food to mouth (digestive system)
waste leaves through mouth
no organs, cells organized instead of tissues, outer layer is protection and inner layer is used for digestion
live in water
Polyp or Medusa Form
reproduce sexually and asexually
Adaptation - coral produces a skeleton to protect its soft body; some sting its predators with tentacles
What characteristics do all cnidarians have in common? They all have tentacles, are carnivores, have radial symmetry, have stinging cells, and live in water.
Echinoderms are invertebrates that have internal skeletons and spines sticking out from their bodies
examples: starfish, sand dollars, sea urchins, sea cucumbers
Interval skeletons and spines
live only in the ocean
get oxygen from seawater
most adults appear to have radial symmetry
no head or brain
Reproduce sexually and asexually
Adaptation - Mouth is at the center of underside with powerful jaws and hidden among their spines and poison glands. They also have tube feet for moving, feeding and sensing respiration