Invertebrates

Arthropods, Mollusks, Echinoderms, Round Worms, Alivia Peggs

Arthropods, Mollusks, Echinoderms, Round Worms

arthropod - is a animal that has a jointed exoskeleton

Crustaceans - one kind of Arthropods. Crabs,lobster

arachnids -

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.



Name two characteristics arthropods share. -

They have legs and a digestive system with two openings


Helpful and Harmful Arthropods


How do arthropods help people?



Echinoderms

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 respirations



Mollusk - an animal is an animal with a soft body and no bones

Example: clams, Octopoda, slugs, snails, squids.


Characteristics

- have no bones

- some have shells

- some the mantle is a tough layer of skin

- reproduce sexually



Adaptations -


Name two characteristics of snails?

The shell of a snail protects the snail from predictors

The snail takes the shell on it back everywhere