Could you add a little more to this question, please?
        
                    
             
        
        
        
Despite their frequency in the intertidal zone, in tide pools, sea urchins can be found at many different depths and in any habitats. They can also be found in nearly any ocean temperature. Sea urchins inhabit the polar seas as well as the warm tropics.
        
             
        
        
        
Answer:
Alveoli are tiny, balloon-shaped air sacs. Their job is to move oxygen and carbon dioxide (CO2) molecules into and out of your bloodstream.
Explanation:
 
        
             
        
        
        
Explanation:
we all find ourselves confronted with the age-old question: 
what happens when you fall into a black hole?
You might expect to get crushed, or maybe torn to pieces. But the reality is stranger than that.
The instant you entered the black hole, reality would split in two. In one, you would be instantly incinerated, and in the other you would plunge on into the black hole utterly unharmed.
Hope this helps you.. Good Luck