Here are some sentences.
Sea urchins have spines.
Have you ever seen a sea urchin?
No. Sea urchins live in the sea.
More sea urchins.
sea urchins can either reproduce sexually or asexually sea urchins can either reproduce sexually or asexually
The classification of a Sea Urchin is Echinoidea
there are excatly 3million purple sea urchins
sea urchins eat kelp.
Mostly for protection and also for locomotion.
No. Sea urchins are primary consumers and only eat sea weed, algae and kelp.
in the sea
Any animal need oxygen for respiration.
asexual reproduction
Sea urchins are not as popular a subject for laboratory experimentation as rats or fruit flies, however, they have been studied. Scientists like to study practically everything.