Invertabrates

By: Anna Kendall

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 once they attach as adults

- 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



Arthropod

arthropod - an animal that has a jointed exoskeleton

Crustaceans - one kind of arthropod. Lobsters, crabs,

arachnids - spiders, scorpions, mites - have eight legs, no antennae, book lungs

Insects - animals with six jointed legs and many have wings (largest group of arthropods)


Characteristics

exoskeleton covers and protects body and gives it support

jointed legs

jointed body

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


Adaptations

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.



Roundworms

Roundworm - a worm with a round, tube like body. Most are too small to be seen.

Example: hookworm


Characteristics

digestive system with 2 openings

take in food and eliminate waste

muscles that run length of body

reproduce sexually

nervous system with brain and simple sense organs



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