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