Page 16 - One Million Things: Animal Life - The Incredible Visual Guide

1 Cerebral ganglion is a group of nerve cells that forms the flatworm’s brain

branch of intestine Mouth lengthwise Front branch of intestine Excretory tubule
Rear removes waste
Cavity called the pharynx sucks food in through the mouth Longitudinal nerve cord runs through the body Digestive pouches absorb food

Stomach receives food from mouth on underside of starfish Tube foot extends the water vascular system is squeezed
share similar needs. They have to move, take in food and oxygen
to supply energy, respond to their surroundings, and reproduce.
In this snapshot of selected invertebrates, you can see the body
Around 97 percent of animal species are invertebrates. Unlike
vertebrates, they lack a backbone. The groups of invertebrate
animals are diverse and have little in common. However, all
organs and systems that meet these needs in three different
Protective cuticle covers the outside of the starfish when fluid from into it
types of invertebrate—flatworms, starfish, and lobsters.
INVERTEBRATES
Radial nerve controls movement of tube feet

Radial canal vascular system

2 of water

Tube feet Paired gonads in each arm release either eggs or sperm Hard, interlocking ossicles form skeleton

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