ATP and Energy
All Cells need energy. (Ability to perform work)
What do cells use energy for?
What Is ATP?
• ATP – adenosine triphosphate is a chemical
molecule made up of an adenine + ribose
(adenosine), and 3 phosphate groups. It is like
a battery!
Adenine
Ribose
How Does ATP Work?
• Energy is stored in the bond between the
phosphate groups.
• When the end phosphates break off, energy is
released!
• (ATP-ADP-AMP)
Adenine
Ribose
ATP = Energy Currency
• Within the cell, formation of ATP from ADP and
phosphate (ADP +PATP) occurs over and over,
storing energy each time.
• As the cell uses energy, ATP breaks down repeatedly
to release energy and form ADP and phosphate.
How do cells perform anabolic and catabolic
reactions?
• Building and tearing down compounds
in a cell (like making and using ATP)
need to be highly regulated.
• Cells regulate these processes of
building up (anabolic) and tearing
down (catabolic) by using special
proteins called enzymes. (Catalyst)
• Enzymes are protected in a cell so
they don’t denature.
Enzymes
Without enzymes, a cell would not be able to perform reactions
which help it to create energy to live! Notice that the purple object
below is an enzyme.
What happens to the green objects in each picture if enzymes are
removed?
Anabolic reactions
require energy
Catabolic reactions release
energy
• The 2 most important processes that use
enzymes as catalysts to make or use ATP
are: