MCAT

1. 1
BIOENERGETICS

2. 2
What is Bioenergetics?
The study of
energy in living
systems
(environments)
and the
organisms
(plants and
animals) that
utilize them

3. 3
Energy
 Required by
all organisms
 May be
Kinetic or
Potential
energy

4. 4
Kinetic Energy
 Energy of
Motion
 Heat and
light energy
are
examples

5. 5
Potential Energy
 Energy of
position
 Includes
energy
stored in
chemical
bonds

6. 6
Two Types of
Energy Reactions

7. 7
Endergonic Reactions
 Chemical reaction that
requires a net input of
energy.
 Photosynthesis
6CO2+ 6H2O C6H12O6 + 6O2
SUN
photons
Light
Energy
(glucose)

8. 8
Exergonic Reactions
 Chemical reactions that
releases energy
 Cellular Respiration
C6H12O6 + 6O2  6CO2 + 6H2O+ ATP
(glucose)
Energy

9. 9
Metabolic Reactions
of Cells

10. 10
What is Metabolism?
 The sum total
of the
chemical
activities of
all cells.

11. 11
Two Types of Metabolism
 Anabolic
Pathways
 Catabolic
Pathways

12. 12
Anabolic Pathway
 Metabolic reactions, which
consume energy (endergonic), to
build complicated molecules from
simpler compounds.
 Photosynthesis
6CO2 + 6H2O  C6H12O6 + 6O2
SUN
light
energy
(glucose)

13. 13
Catabolic Pathway
 Metabolic reactions which release
energy (exergonic) by breaking
down complex molecules in simpler
compounds
 Cellular Respiration
C6H12O6 + 6O2  6CO2 + 6H2O + ATP
(glucose)
energy

14. 14
Cellular Energy -
ATP
Copyright Cmassengale

15. 15
ATP
 Components:
1. adenine: nitrogenous base
2. ribose: five carbon sugar
3.phosphate group: chain of 3
ribose
adenine
P P P
phosphate group

16. 16
Adenosine Triphosphate
 Three
phosphate
groups-(two
with high
energy bonds
 Last phosphate
group (PO4)
contains the
MOST energy

17. 17
Breaking the Bonds of ATP
 Process is called
phosphorylation
 Occurs continually
in cells
 Enzyme ATP-ase
can weaken &
break last PO4
bond releasing
energy & free PO4

18. 18
How does ATP work ?
 Organisms use enzymes to
break down energy-rich
glucose to release its
potential energy
 This energy is trapped and
stored in the form of
adenosine triphosphate(ATP)

19. 19
How Much ATP Do Cells Use?
 It is estimated
that each cell
will generate
and consume
approximately
10,000,000
molecules of
ATP per second

20. 20
Coupled Reaction - ATP
 The exergonic
hydrolysis of ATP
is coupled with
the endergonic
dehydration
process by
transferring a
phosphate group
to another
molecule.
H2O
H2O

21. 21
Hydrolysis of ATP
ATP + H2O  ADP + P
(exergonic)
Hydrolysis
(add water)
P P P
Adenosine triphosphate (ATP)
P P P
+
Adenosine diphosphate (ADP)

22. 22
Hyrolysis is Exergonic
Energy
Used
by
Cells

23. 23
Dehydration of ATP
ADP + P  ATP + H2O
(endergonic)
P P P
Adenosine triphosphate (ATP)
P P P
+
Adenosine diphosphate (ADP)
Dehydration
(Remove H2O

24. 24
Dehydration is Endergonic
Energy
is
restored
in
Chemical
Bonds