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Why do living things need water? |
Question Date: 2018-01-08 | | Answer 1:
Living things need water for many reasons. One of
the most important reasons is that water can
dissolve many substances that organisms need to
survive, and carry these substances to their
destinations.
The way that life has developed on Earth,
other liquids such as oils and alcohols would be
inappropriate for dissolving and carrying these
substances because oils and alcohols may also
dissolve and disrupt cells. Another crucial reason
is that water helps regulate the acidity
(measured by pH) of the mixtures in all
organisms. Many living organisms prefer to
stay at neutral pH, which means neither
acidic or basic, and water helps with this
stabilization process. Changing the acidity of
solutions in living organisms changes the chemical
reactions that can happen in these organisms and
therefore the entire process of life!
A third, equally important reason is that
water helps maintain the right pressures of
cells in living things, by coming in and out
of cells constantly. Imagine a balloon that pops
from too much air pressure on the inside, or a
balloon that collapses from too much air pressure
on the outside. Without water, our cells would
pop or collapse from too much pressure on the
inside or outside like the balloon. These are
just a few of the reasons that living things like
us need water.
| | Answer 2:
Life uses water as a solvent: all of the
chemical reactions that sustain life happen in
water. Without water, these chemical reactions
can't happen.
| | Answer 3:
Living things need water because they are
made of water. Most living things are 70-80%
water
and some organisms like the jellyfish are 95%
water. In a sense, when we drink water we are
replacing a part of ourselves, like replacing
a brick in an old building. The reason why water
is such an important part of living things
probably has to do with how living things
originated. One perspective is that life
originated in the ocean and therefore must be made
from the ocean. In other words, life must be made
of water. Chemically speaking, water has a lot
of useful traits for living things.
Water is a liquid that flows
which means that it can transport molecules
from one part of a cell to another part . It
also dissolves a variety of molecules so
that these molecules can interact with each other
in the water. Another useful property is that
water doesn’t mix with oil. This is
important because oil is what forms the
membrane of the cell and separates it from its
surroundings. If oil mixed well with water,
then fully enclosed cells could not occur in the
current way. Water has so many useful
properties that allow life that it would be
nearly impossible to list them all here.
| | Answer 4:
Water is essential to a variety of functions
necessary for life. Many of the compounds that
cells need to consume or eliminate are soluble in
water, making water a convenient vehicle for
transport of those substances. Water also has
a high specific heat, meaning it takes a
lot of energy to change the temperature of water.
This property makes water useful for regulating
temperature. Water finds yet another use in
mediating many of the myriad chemical reactions
which enable life, such as photosynthesis and
the breakdown of energy storage molecules .
All that being said, none of this is necessarily
unique to water. Essentially all of these
properties stem from the polarity of the
water molecule, which means other polar
compounds have the potential to be the basis of
some form of life. One such contender is ammonia. | | Answer 5:
Every living thing as we know it require
water. Water helps us deliver nutrients and
molecules to our cells so that they can continue
producing energy for us. It also helps us remove
the bad particles from our body. Water also helps
animals regulate their body temperature, like
mammals (you and me!) | | Answer 6:
The complex chemical reactions required to
convert sunlight or food into energy, to regulate
biochemical reactions, to transport molecules, to
grow, to reproduce, and essentially to perform all
the chemistry of life must be done in an aqueous
(in water) environment. The main reason for this
is that some of the molecules involved in these
processes can ionize in water, meaning that
they dissolve into positive and negative species
surrounded by water molecules. This makes them
more reactive and lowers the activation energy for
many important biochemical reactions that would be
impossible outside of water.
Additionally, because the molecules are
dissolved in water, they are more mobile and can
diffuse, making it is easer for reactive species
to come together and react to form chemical
products which in turn then can diffuse to where
they are needed in the cell. Click Here to return to the search form.
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