Re: What is the biological significance of water?

Hello Margaux,

Perhaps a useful way to address this question is 
first to think generally and then focus on 
specifics. Generally, the main biological 
importance of water is that life, with which we 
are familiar, cannot exist without it. In fact, on 
a percent basis, the majority of any organism is 
comprised of water.  Additionally, it is believed 
that life first originated in bodies of water on 
the earth.  

What does water do that makes it so crucial to 
life.  If we examine life in a simplified view, an 
organism relies on enzymes to conduct the 
functions necessary to live. Water provides an 
excellent environment for these enzymes to 
carry forth their functions. The chemical nature 
of water is well suited to serve as a medium for 
enzymes .  It is chemically stable and relatively 
inert therefore it will not disrupt the chemical 
functions of enzymes or other cellular 
components. If there was no water in a cell how 
would enzyme and substrate join together? This 
explanation is what I believe to be the essential 
biological importance of water.. However, you 
are correct in stating that there are many 
reasons why water is significant in life. If you 
continue your study on the chemical nature of 
water and relate it to the physiology of a cell 
and/or a whole organism you will find other 
interesting reasons how water plays an 
important role in the life of an organism.  A 
good introductory chapter on the biological 
relevance of water can be found in Biology by 
Neil Campbell, The Benjamin/Cummings 
Publishing Company, other introductory biology 
texts may also be a good place to start.

I hope this helps.

Chris