Invertebrates
Animals of all kinds
Sponges
Sponge - one type of animal that filters the water it lives in to get food.
Example - Venus-Flower Basket,
Characteristics
- reproduce asexually
- can’t move
- gets food from environment around it.
- between inner and outer layer there is a jelly-like layer
- grow at almost any depth
- grow on hard surfaces
- shaped like fingers, tree branches or round
- filters water to get its food
- 5000 known species
-no real digestive system
Adaptation - body is a network of tiny pores and canals that allow water to filter through to obtain food because they don’t move.
Arthropods
arthropod - An animal that has a jointed exoskeleton and jointed limbs
Crustaceans - A kind of arthropod with three body segments such as a lobster that has a head, thorax, and an abdomen.
arachnids - An arthropod such as a spider that contain 8 legs and no antennae
Insects - An arthropod such as a grasshopper that are the largest group with six jointed legs
Characteristics
- Has legs
- A digestive system with two openings
- A circulatory system
- Has a brain
Adaptations
Muscles attached to the inside of the exoskeleton contract and relax which allows for complex movements.
How do arthropods help people?
- Are a food source for other animals
- Some Arthropods such as bees produce wax and honey
- Many pollinate flowers
- Help other animals reproduce
- Eat insects that destroy crops or flowers
Echinoderms
Echinoderms - are invertebrates that have internal skeletons and spines sticking out from their bodies
examples: starfish, sand dollars, sea urchins, sea cucumbers
Characteristics
Interval skeletons and spines
live only in the ocean
get oxygen from seawater
most adults appear to have radial symmetry
spiny skin
endoskeleton
no head or brain
tube feet
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