The Flow of Energy


Benchmark 3.2: There is a relationship between
the processes of photosynthesis and cellular
respiration. (for example: in terms of energy
and products)
Assessment Objectives:



3.2a Describe the process of photosynthesis.
3.2b Describe the process of cellular respiration.
3.2c Relate the processes of photosynthesis and
cellular respiration.
Free energy (1:30)
 ATP (7:15)
 Aerobic Cellular Respiration (5:35)
 Anaerobic respiration (4:09)
 Lactic acid & ethanol fermentation (1:30)
 Electromagnetic song (4:00)
 Photosynthesis (2:10)
 Photosynthesis & Calvin cycle (3:45)
 Cellular respiration (1:54)
 From food to ATP (1:56)
 Metabolic Pathways (1:02)
 Limits of Life (1:20)
Total time: 34:06 minutes + 19:00 at the end









Absorption spectrum
Aerobic respiration
Alcoholic
fermentation
Anaerobic
ATP
Calvin cycle
carotenoid
endergonic








Exergonic
Free energy
Grana
Lactic acid
fermentation
Light reactions
Stroma
Visible spectrum
wavelength





Energy is the ability to do
work.
Cells must have energy to
carry out the work of
living.
Energy available to do
work is called free energy.
Free energy is used for
muscle contraction, active
transport and protein
synthesis.
Endergonic reactions
absorb energy that has
been released from
exergonic reactions.
FREE ENERGY (1:30)





In cells, most of the energy
needed for an endergonic
reaction comes from the
exergonic reaction from
breaking up molecules of
ATP.
When the bond between
two phosphate groups
breaks, energy is released.
Hydrolysis of ATP is
represented by the reaction:
ATP + H2O  ADP + Pi + energy
Thus, the potential energy
of ADP compared to ATP is
lower.
ATP (7:15)
Adenosine triphosphate


When plants make sucrose from glucose and fructose, an
input of energy is required. That energy comes from the
breakdown of ATP to form ADP and inorganic phosphate.
Each reaction takes place with the help of an enzyme which
reduces activation energy.

ATP + glucose ADP + glucose – P

Glucose – P + fructose  sucrose + Pi

Net reaction:

ATP + glucose + fructose sucrose + ADP + Pi


During cellular
respiration, some of the
energy released by
breaking the bonds of
food molecules such as
glucose is used to make
ATP from ADP. Then
ATP is used as needed.
Respiration in cells that
require oxygen is called
aerobic respiration.
Aerobic Cellular Respiration (5:35)


Anaerobic respiration
occurs without oxygen.
When your muscles are
fatigued, it’s because
there’s not enough
oxygen for aerobic
respiration. Instead,
muscle cells are
undergoing anaerobic
processes to release
needed energy.
Anaerobic processes
take place in the
absence of oxygen.
Anaerobic respiration (4:09)

Lactic Acid Fermentation:

Glucose + 4ADP + 4Pi produces lactic acid and 4ATP

Alcoholic Fermentation:



Glucose + 4ADP + 4Pi produces ethanol, carbon
dioxide and 4ATP
Notice that when compared with aerobic
respiration, anaerobic respiration produces
much less ATP. Oxygen is your friend.
Lactic acid and ethanol fermentation (13:25 Hank)
Electromagnetic song (4:00)








Eureka! 4:05


A wavelength is the distance
between crests or troughs.
The visible light spectrum is
also known as white light, is
made up of all colors.
From longest to shortest
wavelength, the
electromagnetic spectrum
goes:
Radio waves
Microwaves
Infrared radiation
Visible light
Ultraviolet
Xrays
Gamma Rays





Okay, now that we’re done with the song, what
is photosynthesis?
Molecules of carbon dioxide and water
combine into simple sugars (glucose, fructose
or other 6-carbon sugars) by enzymes and
oxygen is given off as a by-product in this
endergonic reaction:
6CO2 + 6H2O  C6H12O6 + 6O2
The importance of photosynthesis (2:10)
Photosynthesis Interactive
CHLOROPLAST
PIECES AND PARTS





Stroma is the “watery” part
of the chloroplast.
Grana is a series of stacked
thylakoid disks containing
chlorophyll; found in the
inner membrane of
chloroplasts.
Thylakoid is where light
reactions take place for
photosynthesis.
Carotenoids are pigments
that range from yellow to
red.
Chlorophyll is also a
pigment that is _______ in
color.


The Calvin Cycle takes
place in the stroma—the
fluid part of the
chloroplast.
Enzymes combine with
CO2 from air or water
with hydrogen from
NADPH and energy from
ATP to form 3-carbon
simple sugars. Many of
these sugars are used to
form 6-carbon sugars,
which make up sucrose,
starch , and cellulose.
Photosynthesis and the Calvin Cycle (3:45)
PHOTOSYNTHESIS


An endergonic reaction
with water and carbon
dioxide combining in
the presence of light
and enzymes to
produce simple sugars
and oxygen.
6CO2 + 6H2O  C6H12O6 + 6O2
CELLULAR
RESPIRATION(1:54)



An exergonic reaction
with simple sugars
reacting with oxygen
and breaking down in
the presence of enzymes
into oxygen and water.
C6H12O6 + 6O2  6CO2 + 6H2O
The light used to make the
sugars is transferred into ATP
which, once used is released as
heat.

From Food to ATP (1:56)

Metabolic Pathways (1:02)

The Limits of Life (1:20)