Answer:Species Dynamics. This theory is quite straightforward: species that can colonize new areas faster and reproduce in greater number than they become extinct have the greatest chances to thrive. The tropics offer favorable conditions for these conditions to be met.    
There Is More Diversity Near the Equator. ... Another argues that more solar energy is received around the equator, allowing for greater species richness. A third points out that equatorial tropics are the largest biome, so it makes sense that there would be more species.
Explanation:
 
        
             
        
        
        
White Blood cells or WBC's are the cells of your immune system. They are your first defense in fighting off foreign invaders and infectious diseases.
-Medical Student (College Level)
 
        
             
        
        
        
Hi there!
<u>Electronegativity</u> is the concept of how likely an atom is to attract the shared molecules in one of these bonds to itself. We know the molecule water is made up of two hydrogens and one oxygen. The electronegativity of hydrogen is 2.2, and oxygen 3.4. An <u>ionic bond</u> needs at least a difference in electronegativity of 1.6. As the difference is less than that, we can say that water is a covalent molecule. This then wipes out choice B, because it is not ionic, and C, as we have seen it is actually covalent.
Now, we can see the difference in electronegativity between oxygen and hydrogen is still 1.2. This means that while it is not at the point for there to be an ionic bond, there is still a difference in attraction, where the electrons will tend to favor the oxygen more and 'hang around it' more. As electrons are <u>negatively charged</u><em><u>,</u></em> this means that the oxygen will gain a slightly negative charge. This then makes the molecule polar, because it now has a charge within the molecule. This means we have our answer, choice D.
In terms of hydrophobic molecules - they tend to be ones without a charge. (If you're interested in this kind of stuff, I'd search hydrophobic up, and possibly also look into hydrogen bonds).
Hope this helps! Feel free to ask me any other questions you have about this specific problem.
 
        
             
        
        
        
I would say pelagic isn't a zone of ponds and lakes. A pelagic zone is more a zone of the sea rather than ponds and lakes.