Because since the water is ocean water and it’s impure, the impure water freezes at the top while the “clean” water is at the bottom.
<h2>
Answer:</h2>
<h3>
<em>OPTION</em><em> </em><em>B</em><em> </em><em>IS</em><em> </em><em>THE</em><em> </em><em>CORRECT</em><em> </em><em>ANSWER</em></h3>
<em> </em>
<h2>
Explanation:</h2>
<h3>Nucleocytoplasmic exchange of materials</h3>
<h3>In eukaryotic cells, the nucleus is bound by a double membrane or nuclear envelope. It possesses openings at certain intervals called as 'nuclear pore'. Nuclear pores are large protein complexes regulates the exchange of material between nucleus and cytoplasm, i.e., nucleo-cytoplasmic exchange of materials. </h3><h3 />
Answer:
A. True
Explanation:
Carbohydrates, lipids, proteins, and nucleic acids are the four major classes of biological macromolecules.
Amino acids have the structure
COOH-C(H)(R)-NH2
The differences are in the R-groups where different functional groups in the r-groups of each amino acid causes them to have different properties (ie. some are acidic and some are basic)