Ask A Scientist Molecular Biology Archive

name         Carmen V.
status       student
age          14

Question -   Why is it important to have cell membranes as barriers?
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I'm not quite sure what you are asking, but the cell membrane serves a very 
important function in defining the border of the cell. Without it, it would 
be like a house with no exterior walls. The cell membrane (and the proteins 
that are associated with it) is also very selective in what it allows to pass 
into or out of the cell, which is important. As a result, the interior of the 
cell can have different concentrations of molecules than are found in the 
surrounding environment. 

Paul Mahoney 
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What if there weren't cell membranes?  How could the cell control what came in and 
out.  For that matter, why would the cell even be separate from its environment?

Van Hoeck
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First off for any individual cell to be an individual cell it must have a
limit to where it begins and is separated from its environment. Second the
typical cell membrane is extremely complex. Thousands of scentific research
papers are written each year on it. It is what decides what the cell will
allow in and out, how it attaches to its surroundings and how it
communicates with other cells to name a few of its main functions. It is
also very dynamic and fluid. In a way the memebrane is the eyes, ears, nose
and voice of a cell.

Pf
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