CELL STRUCTURES AND FUNCTION
CELL STRUCTURE
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Nonpolar
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Polar
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Either A or B
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None of the above
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Detailed explanation-1: -The main component of the cell membrane is a phospholipid bi-layer or sandwich. The heads (the phospho part) are polar while the tails (the lipid part) are non-polar.
Detailed explanation-2: -Lipids, i.e., fatty molecules, on the other hand, are non-polar, meaning that the charge distribution is evenly distributed, and the molecules do not have positive and negatively charged ends..
Detailed explanation-3: -However, the bonding between carbon and hydrogen atoms in lipids is not polar. This is because the electrons in the covalent bonds are shared equally between the carbons and the hydrogens and there are no partial charges anywhere. Thus, long chains of carbon-hydrogens bonds form a nonpolar molecule.
Detailed explanation-4: -The nonpolar fatty acid “tail” group consists of three hydrocarbons (a functional group composed of C-H bonds) that also have a polar carboxyl functional group (hence the term “fatty acid"-the carboxyl group is acidic at most biologically relevant pHs).