3. From food webs to the life of a cell
energy
energy
energy
4. Flow of energy through life
Life is built on chemical reactions transforming energy
from one form to another
organic molecules →
ATP & organic molecules
organic molecules →
ATP
& organic molecules
sun
solar energy →
ATP & organic molecules
11. Energy and Life!!
+ + energy
+ energy+
digestion
synthesis
Orgs couple exergonic reactions
(releasing energy) w/ endergonic
reactions (needing energy)
12. Question 3!
What is the first rule of thermodynamics?
Energy cannot be created nor destroyed
13. Question 4!
What is the second rule of
thermodynamics?
No reactions is
100% efficient
Every energy
transfer or
transformation
increases
entropy of
universe
14. AT
P
The Living Body
• Fuel = eat high energy org. molecules and break
down
catabolism capture released energy in a form
cell can use
• Need an energy currency, a way to pass energy
around ATP = short term energy storage molecule
16. How does ATP store energy?
• Each negative PO4 more difficult to add
• a lot of stored energy in each bond
• most energy stored in 3rd Pi
• 3rd Pi is hardest group to keep bonded to
molecule
• Bonding of negative Pi groups is unstable
• spring-loaded
• Pi
O– O– O– O– O–
–O P –O– P –O –PO OP –
O– P O– O O O
O O
Instability of its P bonds makes ATP an excellent energy donor
I think
he’s a bit
unstable…
don’t you?
AA
DTP
P