Chapter 8 - Photosynthesis
Plant – multicellular eukaryotes that do
photosynthesis.
“stationary animals that eat sunlight”
Adenosine Triphosphate (ATP)
One of the most important compounds that cells use.
Stores and releases energy - adenosine triphosphate
(ATP).
 ATP consists of adenine, a 5-carbon sugar called
ribose, and three phosphate groups.

Adenosine Triphosphate (ATP)
Adenosine diphosphate
(ADP) has two phosphate
groups instead of three. ADP
does not contain as much
energy as ATP. Another P is
added to ADP to form ATP.
 Cells release the energy stored
in ATP by breaking the bonds
between the second and third
phosphate groups.

Uses of ATP
Powers protein pumps in the
cell membrane
 Powers cilia and flagella
 Power for synthesis of
proteins
 Powers proteins that contract
muscles
 Provides cell energy

How could a small seed become a giant tree?
Heterotroph – obtains energy
from food it consumes
Autotroph – uses energy
from the sun to produce food
Photosynthesis - autotrophs
convert the energy from
sunlight to produce high-energy
carbohydrates (glucose)
Autotroph or Heterotroph
Photosynthesis
CO2 + H2O
Carbon
Dioxide
LIGHT
C6H12O6 + O2
Glucose
Water
Oxygen
Photosynthesis

Takes place in the
chloroplast



Thylakoids – saclike
photosynthetic
membrane in the
chloroplast
Grana – stacks of
thylakoids
Stroma - the region
outside of the thylakoid
membranes
Photosynthesis (Overall)
H2O
CO2
Chloroplast
Light
NADP+
ADP
Light
+
Dark
P
CALVIN
CYCLE
(in stroma)
LIGHT
REACTIONS
(in thylakoids)
ATP
NADPH
O
Sugar
Factors Affecting Photosynthesis


Shortage of water
Temperature


Photosynthesis is
controlled by enzymes
that work best between 0
C and 35 C.
Light Intensity

More light increases rate
of photosynthesis
Chapter 9: Cellular Respiration
9-1 Chemical Pathways
Chemical Energy and Food

Cellular respiration happens slowly and in many
steps.

If all the energy was release in one step . . . Most
would be lost as light and heat!
 Cellular respiration breaks down glucose
molecules and banks their energy in ATP
Chemical Energy and Food
PHOTOSYNTHESIS
CO
HO
2
2
___________
+ _________
+ ___________
C6H12O6 + __________
O2
→_______________
CELLULAR RESPIRATION
C6H12O6 + _________
CO2 + __________
H2O
O2 →________
_____________
+ __________
The two equations are exact opposites!
Overview
of
Cellular
Respiration
Occurs in three main steps
Step 1: Glycolysis
 Occurs in the cytoplasm
 Breaks down glucose
producing a small amount
of ATP
Step 2: Krebs cycle
 Takes place in the
mitochondria
 Completely breaks down
glucose, produces a small
amount of ATP
 Provides third stage of cell
respiration with electrons
Stage 1
Stage 2
Stage 3
Overview of Cellular Respiration

Cellular respiration
 Step 3: Electron Transport
Chain (ETC)
 Occurs in the mitochondria
 Uses the energy released
from electrons to produce
ATP
Stage 3
Overview of Cellular Respiration
NADH
High-energy electrons
carried by NADH
NADH
FADH2
and
Step 1
Step 3
Step 2
GLYCOLYSIS
Glucose
(Electron Transport
Chain)
Krebs
Cycle
Pyruvate
Mitochondrion
Cytoplasm
ATP
Substrate-level
phosphorylation
CO2
CO2
ATP
ATP
Substrate-level
phosphorylation
Oxidative
phosphorylation
Mitochondria Structure
•
•
•
•
•
Has a double membrane, with an intermembrane
space between the two layers.
Cristae are folds of the inner membrane
The matrix is the innermost compartment, which is
filled with a gel-like fluid.
Krebs Cycle occurs in the matrix.
ETC occurs on the inner membrane.
Organize your thoughts
Working in pairs at your tables please address the
following:

What is the chemical equation for photosynthesis
(reactants/products)

What is light? How does it play a role in
photosynthesis?

Write down everything that you already know
about photosynthesis.

Lastly, what is it that you don’t understand about
plants or photosynthesis?
Green Solar Cells
1.
2.
3.
4.
5.
What is responsible for the various shades of
green in plants?
What is the function of the stroma lamellae?
What evidence supports the theory that
chloroplast were once invasive cells?
How is excess food stored?
How does the author define photosynthesis?
5
6
2
4
1
3
Photosynthesis – Light and Dark Reactions
1 H2O
3CO2
Chloroplast
Light
NADP+
ADP
+
P
Light
CALVIN
CYCLE
(in stroma)
LIGHT
REACTIONS
(in thylakoids)
ATP
NADPH
2
O
4
Sugar
Dark
Dark Reaction (Calvin Cycle)
1._______
3.___________
2._______________
4._____________
5._____________
6._______
7._______
Homework (for Thurs. 12/9):
1. In text read pgs 230-233
2. In 8.2 assessment on pg 234
answer question #1,2 and 3 all
parts of each question
Using the light reaction diagram:
On your own, describe the four
steps of the light reaction in your
own words. Use complete
sentences.
In pairs:
1.
2.
3.
4.
See if you can write the chemical
equation for photosynthesis (inputs and
outputs)
What is the organelle in plant cells that is
most involved with photosynthesis
Explain why this organelle captures
energy
If you had to summarize light (from the
sun or from a bulb) in one word what
would it be?
Light Reaction
8.
H+ Concentration =
10.
4.
7.
9.
Type of transport =
5.
Type of Transport =
1.
2.
3.
6.
H+ Concentration =