Pentamerous
Toothpick
Dome
Porcupine
Because the eggs make great omlettes
Because sea urchins have large numbers of eggs
Because sea urchins have large numbers of relatively big eggs
Because a sea urchin's egg is relatively big
Animalia
Strongylocentrotus
Purpuratus
Echinoderms
Small fish
Sea cucumbers
Other sea urchins
Algae
Mouth
Nose
Spine
Feet
On the beach
Intertidal area only
Both intertidal area and subtidal areas
Subtidal area only