Answer 1:
This is a pretty sophisticated question. ATP
is short for "adenosine triphosphate" which
means there's one adenosine 3 phosphates in this
molecule. I'm guessing that you know that ATP
is basically a way for the cells of your body to
store energy. To make things a little simpler,
think of ATP as having 4 parts: the A (adenosine)
and 3 P's (the phosphates). The energy is not
stored in the A or the P's, but in the BONDS
between the molecules. An ATP is kind of like
a charged battery. When you take off one P, you
get adenosine diphosphate or ADP (which is
an A and 2 P's) plus an extra P. You also release
a bunch of energy that can be used by the cell to
do work.
So an ADP is like a battery that has lost
some of its charge. You can take off another P
and get adenosine monophosphate (AMP) and
another spare P, but your body usually uses AMP
for sending signals, so let's ignore that. There
are pictures of these molecules at:
adenosine triphosphate .
Actually they're not true pictures because ATP
is way too small to see, but they are models that
show how we think they are put together.
ATP is a sort of "universal power source"
that allows your body to take the energy from
pizza, carrots, or milk and turn it all into the
same type of energy. It's sort of like the way we
use electricity for most of our power needs even
though the energy was once in the form of coal,
water behind a dam, the inside of an atom, or
something else. You wouldn't want to shovel coal
into your calculator. In the same way, it's
easier for all your cell's systems to use the same
kind of power: ATP.
Where does almost all of the energy on Earth
come from?
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