Cells
and
Energy
Use
Metabolism
• Metabolism refers to
sum of all energy use
in the cell or body.
• Why is energy needed?
To do the things
necessary for life:
– Energy use is necessary to
maintain organization.
– Energy is needed for
movement, and control of body.
– Energy is also needed for
growth and reproduction.
What is Energy?
• Energy is the ability
to do work.
• What is free energy?
– Free energy is what’s
available within the cell to
do work.
How is Energy Stored in
molecules?
– Chemical energy is stored
in chemical bonds.
• Where does a cell
energy come from?
– Cells energy comes from
breaking covalent bonds.
Where energy is produced in the cell
•
Energy is produced in
•
How would you describe the
structure of the mitochondria?
•
•
– Cytoplasm
– Mitochondria.
– Outer membrane.
– Folded inner membrane called
the cristae.
– Fluid-like filling called the
matrix.
How did the mitochondria
evolve?
– Endosymbiosis.
– Once free living prokaryotes
What is the evidence?
– They have their own DNA and
can self replicate.
Think: what type of cell would you
expect to be able to produce more
energy, Prokaryotic or Eukaryotic?
Why?
In what form is energy used by the cell?
• ATP is the
cell’s source
of energy.
• How does ATP
act like a
battery in a car?
– Capable of
storing energy.
– Capable of
releasing energy.
the structure of Adenosine Triphosphate
• 1 Adenine molecule +
1 ribose = adenosine.
– 3 phosphates
attached in a
string.
– Where is energy
stored?
– High energy bonds
between the
phosphates.
– Why are they high
energy bonds?
• “-” charges on
phosphates repel.
Think: what kind of molecule is
ribOSE?
How ATP releases energy
• ATP and the release of
energy.
• ATP
ADP + Pi +
free energy.
• How does ATP store energy?
• ATP and the storage of
energy
• ADP + Pi + Free energy
ATP
Summary: answer the following
in paragraph form
1. How is Energy Stored in molecules?
2. Where is energy produced in the cell?
3. What does the T in ATP stand for and
what does the D in ADP stand for?
4. How do the names of ATP & ADP
relate to the to the way cells get
energy from ATP?