CHAPTER 8 Biology about the introduction of photosynthesis.ppt

Photosynthesis

1. CHAPTER 8: CHAPTER 8:
PHOTOSYNTHESISPHOTOSYNTHESIS

2. 8-1 Energy of Life
Energy=
Living organisms depend on energy.
Living things get energy from _______.
The ultimate source of energy is the _____.
The ability to do work
food
sun

3. A.Autotrophs and Heterotrophs
Autotrophs=
oExample: plants use sunlight to make food
Heterotrophs=
oExample: ___________ - eat plants
___________- eat animals that
have stored energy from
plants they eat
___________- eat dead
organisms
Organisms that make their own food
Organisms that need to consume
food for energy
herbivores
carnivores
decomposers

4. Adenine Ribose 3 Phosphate groups
Section 8-1
ATP
B. Chemical Energy and ATP
•Forms of energy: light, heat, electricity, and
•_____ (Adenosine Triphosphate)=
Chemical energy (stored in bonds)
ATP
The basic energy source (chemical energy) of all cells

5. 1.Storing Energy
•ADP (Adenosine Diphosphate) contains ____
phosphates instead of 3.
•If a cell has extra energy,

2. Releasing Energy
•To release energy stored in ATP,
2
Small amounts can be stored by adding a
phosphate group to ADP molecules to produce ATP.
The cell can break the high energy bond between
the 2
nd
and 3
rd
phosphate group

6. ADP ATP
Energy
Energy
Adenosine diphosphate (ADP) + Phosphate Adenosine triphosphate (ATP)
Partially
charged
battery
Fully
charged
battery
Section 8-1
Figure 8-3 Comparison of ADP and ATP to a Battery

7. C.Using Biochemical Energy
How ATP is used in the cell
-
-
-
-
Cells contain a small amount of ATP.
Only enough to provide a few seconds of activity.
ATP is great at ________________ but not good at
C.Glucose stores ___ times more energy than ATP.
The energy stored in Glucose can be used to
Carry out active transport
Aids in moving organelles throughout the cell
Protein synthesis
Producing light (ex. fireflies)
transferring energy
Storing large amounts of energy
90
regenerate ATP when the cell needs it.

8. 8-2 Photosynthesis: An Overview
Photosynthesis=
 Plants convert ______________ → ______________
through a series of oxidation/reduction reactions.




Process where plants use energy from sunlight
to convert water and carbon dioxide into
high-energy sugars and oxygen.
Sunlight energy Chemical energy
6 CO
2
+ 6H
2
O SUNLIGHT C
6
H
12
O
6

(SUGAR)
+ 6O
2

9. 6 CO
2
+ 6H
2
O + SUNLIGHT C
6
H
12
O
6
(SUGAR) + 6O
2


sunlight
O
2

CO
2
H
2
O
C
6H
12O
6

10. Light Energy
Chloroplast
CO
2
+ H
2
O
Sugars + O
2
Section 8-2
Photosynthesis: Reactants and Products

11. A. Investigating Photosynthesis
 Investigations into photosynthesis began with the
following question:
“When a tiny seedling grows into
a tall tree with a mass of several tons,
where does the tree’s increase in mass come from?”

12. 1.______________ Experiment (1643)
Put soil in pot and took mass
Had seedling and took mass
Put seedling in soil...watered...waited five years...
the seedling became a tree.
He concluded that

He determined that

  
                                    
 
   
Van Helmont’s
the mass came from water
Plants need water to grow

13. 2.___________ Experiment (1771)
Put a lit candle in a bell jar-

Placed a mint plant in the jar with the candle-
Concluded
He determined

  
                                      
 
                   
Priestly’s
The flame died out.
Flame lasted longer
plants release a substance needed
for candle burning.
plants release oxygen

14. 3.________________Experiment (1779)
Put aquatic plants in light...
Put aquatic plants in dark...

He determined:
4._______________ (1948)
He determined
Known as the
Jan Ingenhousz
produced oxygen
No oxygen
Light is needed to produce oxygen
Melvin Calvin
carbon’s path to make glucose
Calvin cycle

15. B. Light and Pigments
 Photosynthesis requires ______ (soil), ____________ (air),
and ____ (sun), and ________ (a molecule in chloroplasts).
 Energy from the sun is in the form of _____.
 Sunlight= perceived as white light=
 The wavelengths you can see are part of the
_______________.
 Plants capture light with light absorbing molecules called
________.
 The main pigment is chlorophyll (2 kinds)
1.
2.
water Carbon dioxide
light chlorophyll
light
A mixture of different
wavelengths
Visible Spectrum
pigments
Chlorophyll a
Chlorophyll b

16. Absorption of Light by
Chlorophyll a and Chlorophyll b
VBGYOR
Chlorophyll b
Chlorophyll a
Section
8-2
Figure 8-5 Chlorophyll Light Absorption Chlorophyll absorbs light in the __________ and
___ wavelengths

Gamma
rays
X-rays UV Infrared
Micro-
waves
Radio
waves
Visible light
Wavelength (nm)

Blue-violet
red

17.  Chlorophyll reflects ______ wavelengths (that’s why
plants appear green)
 The energy absorbed by chlorophyll is transferred to
_________ (in chloroplasts) which makes
photosynthesis work.
green
electrons

18. •The location and structure of chloroplasts
Figure 7.2
LEAF CROSS SECTION
MESOPHYLL CELL
LEAF
Chloroplast
Mesophyll
CHLOROPLAST Intermembrane space
Outer
membrane
Inner
membrane
Thylakoid
compartmentThylakoid
Stroma
Granum
StromaGrana

19. Light
Chloroplast
Reflected
light
Absorbed
light
Transmitted
light
8-3 The Reactions of Photosynthesis
A. Inside a Chloroplast
•Site of Photosynthesis=

The chloroplasts

20.  Photosynthesis is a two part process:
1.
-aka:
2.
-aka:
-aka:
-aka:
Chloroplast
Light
O
2
Sugars
CO
2
Light-
Dependent
Reactions
Calvin
Cycle
NADPH
ATP
ADP + P
NADP
+Chloroplast
Figure 8-7 Photosynthesis: An Overview
Light-dependent reactions (located in thylakoid membranes)
Light Reaction
Light-independent reactions (located in stroma)
Dark reaction
Calvin Cycle
Carbon fixation
H
2
0

21. •An overview of photosynthesis
Figure 7.5
Light
Chloroplast
LIGHT
REACTIONS
(in grana)
CALVIN
CYCLE
(in stroma)
E
le
c
tr
o
n
s
H
2
O
O
2
CO
2
NADP
+
ADP
+P
Sugar
ATP
NADPH

22. B. Electron Carriers
 Sunlight energy is transferred to
 The electrons
 High energy electrons require

ANALOGY: If you wanted to transfer hot pizza rolls from the oven you need a special
carrier (oven mitt)
 Electron carriers pass electrons from carrier to carrier
to carrier;
 A Key electron carrier in photosynthesis is NADP
+
.
NADP
+
+ +

→→
(electron carrier) (high energy electrons) (hydrogen ions) (energy storing compound)
 When energy is needed, the
electrons in chlorophyll.
gain a lot of energy.
a special carrier
(molecule/compound).
Forming an electron transport chain.
2e- H
+ NADPH
Covalent bonds of NADPH are broken to release
the high energy electrons.

23. C.Light-Dependent Reactions (Requires Light)
· 
  Located in the ___________________________

· 
  In the light reaction, ___________ is used to
produce
_____ and _______
thylakoid membrane
light energy
ATP NADPH

24. Primary
electron acceptor
Primary
electron acceptor
E
l
e
c
t
r
o
n

t
r
a
n
s
p
o
r
t

c
h
a
i
n
E
l
e
c
t
r
o
n

t
r
a
n
s
p
o
r
t
Photons
PHOTOSYSTEM I
PHOTOSYSTEM II
Energy for
synthesis of
by chemiosmosis
http://www2.kumc.edu/netlearning/examples/flash/photosyn2.html

25. KEY PLAYERS IN LIGHT REACTION:
 
   
Photosystem I and II:
 
  
Electron carriers:
 
   
Water:
• ATP Synthase:
Clusters of chlorophyll pigment
ADP and NADP
+
Donates electrons
Enzyme (protein) that makes ATP

26. Figure 7.7C
Primary
electron acceptor
Photon
Reaction center
PHOTOSYSTEM
Pigment
molecules
of antenna

27. Hydrogen
Ion Movement
Photosystem II
Inner
Thylakoid
Space
Thylakoid
Membrane
Stroma
ATP synthase
Electron
Transport Chain
Photosystem I ATP Formation
Chloroplast
Light Reaction Process:

28. •The production of ATP in photosynthesis
Figure 7.9
Thylakoid
compartment
(high H
+
)
Thylakoid
membrane
Stroma
(low H
+
)
Light
Antenna
molecules
Light
ELECTRON TRANSPORT
CHAIN
PHOTOSYSTEM II PHOTOSYSTEM I ATP SYNTHASE

29. A. Photosystem II (PSII)
* 
Absorbs light to
 
2H
2
O
 
 
e- =
 
O
2
=

  H+=
B. Electron Transport Chain
* The light energy
* The electrons get passed
split (break up) water molecules
→ 4H
+
+ 4e- + O
2
Donated to chlorophyll
Released into air providing oxygen for us
Released inside the thylakoid membrane
excites electrons increasing
their energy level.
down an electron transport chain to
photosystem I (PSI)

30. C. Photosystem I
· 
       Light energy energizes electrons.
· 
       NADP+ accepts the electrons and an H+ and
becomes _________.
 
D. Hydrogen Ion Movement
· 
       When water splits,
· 
       The difference in concentration and charge
 
E. ATP Formation
· 
       _____ do not cross the membrane directly.
They need the help of a membrane protein.
· 
       H+ ions pass through the protein:

NADPH
H+ ions fill up the inner thylakoid space
(making it positively charged). As a result, the
stroma is negatively charged.
Provides the energy to make ATP.
Ions
ATP synthase - an enzyme that converts ADP to ATP

31. PRODUCTS OF THE LIGHT REACTION:
· 
  
____ : Released in the air
· 
______________: Contain a lot of chemical energy but
cannot store it for long. So, they are used to power
the dark reaction to _________________ which
can store the energy for longer periods of time.
O
2
ATP & NADPH
help build glucose

32. ChloropIast
CO
2
Enters the Cycle
Energy Input
5-Carbon
Molecules
Regenerated
Sugars and other compounds
6-Carbon Sugar
Produced
Section 8-3 D. The Calvin Cycle (dark reaction; light independent)
* Occurs in the
Figure 8-11 Calvin Cycle
Stroma with or without light.

33. DARK REACTION PROCESS:
 
A. CO
2
enters the system
• 
           
• product=
B. Energy input
•The _________________________________ are used to
C. 6-Carbon Sugar is produced
•___ of the 12 3-C are used to make glucose and
other compounds.
D. 5-Carbon Molecules Regenerated
•___ remaining 3-C are converted into 6 5-C molecules
6 CO
2
combines with 6 5-C compounds
12 3-C compounds
ATP & NADPH (from the light reaction)
convert the 12 3-C compounds into a higher energy form.
2
10

34. PRODUCTS OF THE CALVIN CYCLE (DARK REACTION):
* 
                  
 
E. Factors Affecting Photosynthesis
* 
        

* 
  Plants often have a ______ coating to protect against
dehydration
*
 
      
* The greater the _____________, the better
photosynthesis functions (up to a point).
High Energy Sugars
Shortage of water can stop/slow down photosynthesis
waxy
Very low/high temperatures (damages enzymes) can
stop/slow down photosynthesis (optimal temp.= 0°– 35° C
Light intensity

35. Photosynthesis
includes
of
take place in
takes place in uses
to produce
to produce
use
Light-
dependent
reactions
Calvin cycle
Thylakoid
membranes
Stroma NADPHATP
Energy from
sunlight
ATP NADPH O
2 Chloroplasts
High-energy
sugars
Section 8-3
Concept Map