Download Chapter 8 - Duplin County Schools

Chapter 8
Photosynthesis
8-1 Energy and Life
All organisms must be able to
produce energy from the
environment in order to live.
 Where do we get our energy???
 What is the Ultimate energy
source???

 ATP
(energy storage molecule)
 Adenosine Tri-Phosphate
 Similar to Gasoline!!!
 Energy is stored in the bonds!!
A
1st
Bonds
P
2nd
P
3rd
P
ATP

Making of ATP:
ADP + P + Energy  ATP

Breaking down of ATP:
ATP  ADP + P + Energy
8-2 Photosynthesis: Trapping
the Sun’s Energy
Photo – synthesis
 Photosynthesis: Converts the energy of
sunlight into chemical energy stored in the
bonds of glucose (C6H12O6) and oxygen


6 CO2 + 6 H2O  C6H12O6 + 6 O2
CARBON DIOXIDE
WATER
GLUCOSE
(PLANT FOOD)
OXYGEN
(PLANT POOP)
6 CO2 + 6 H2O  C6H12O6 + 6 O2
1. Light
2. Enzymes
3. Chlorophyll
CO2 + H2O are Raw Materials!
 C6H12O6 + O2 are Products!

There are two types of organisms:
1.
Autotrophs


2.
Make their own food (photosynthesis /
chemosynthesis)
Most are plants!
Heterotrophs


Eat other organisms
We are heterotrophs
2 Parts to Photosynthesis
Light-dependent
Reaction
 Requires Light
 Photolysis
1.
H2O

Makes Oxygen
Light-independent
Reaction
 Also called Calvin
Cycle or Dark
Reaction
 Does not require
Light
 Makes Glucose
2.
Chemosynthesis
(pg. 68)
Not all autotrophs use the sun for energy.
 Some autotrophs use chemicals through a
process call chemosynthesis
 Tube worms are an example of organisms
that use chemosynthesis.

Chapter 9
Cellular Respiration
9-1 Chemical Pathways
How much energy is actually present in
food?
 A LOT – One gram of glucose C6H12O6
when burned releases 3811 calories of
heat energy
 Calorie: the amount of energy needed to
raise 1 gram of water 1 degree Celsius

 “Big”
C we see on food labels represents a
kilocalorie (1000 calories)
Glycolysis
The breaking down of glucose to release
energy!
 Glycolysis releases a small amount of
energy (1 glucose = 2 ATP)
 IF oxygen is present, glycolysis leads to
two pathways that release a great deal of
energy.
 IF oxygen is absent, glycolysis leads to a
different pathway.

Cellular Respiration
In the presence of oxygen, glycolysis is
followed by the Krebs cycle & the electron
transport chain.
 Glycolysis, the Krebs cycle, & the elctron
transport chain make up a process called
CELLULAR RESPIRATION!!

Cellular Respiration
Equation
C6H12O6 + 6 O2  6 CO2 + 6 H2O + Energy
Two types of Respiration:
1)
Aerobic  Requires Oxygen
More Energy
2)
Anaerobic 
Does Not Require Oxygen
Less Energy
Two types of fermentation:
Lactic Acid Fermentation
1)
•
•
Anaerobic
End product, Lactic Acid
Alcoholic Fermentation
2)
•
•
Anaerobic
End product, alcohol
Compare cellular respiration and
photosynthesis
Function
Photosynthesis Cellular
Respiration
Energy Capture Energy Release
Location
Chloroplasts
Mitochondria
Reactants
CO2 & H2O
C6H12O6 & O2
Products
C6H12O6 & O2
CO2 & H2O