Download 8-2 Photosynthesis: An Overview

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

Cyanobacteria wikipedia, lookup

Light-dependent reactions wikipedia, lookup

Photosynthetic reaction centre wikipedia, lookup

Transcript
Biology
Slide
1 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An
Overview
Slide
2 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
8-2 Photosynthesis: An
Overview
The key cellular process identified with energy
production is photosynthesis.
Photosynthesis is the process in which green
plants use the energy of sunlight to convert water
and carbon dioxide into high-energy carbohydrates
and oxygen.
Slide
3 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
The Photosynthesis
Equation
What is the overall equation for
photosynthesis?
Slide
4 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
The Photosynthesis
Equation
The Photosynthesis Equation
The equation for photosynthesis is:
6CO2 + 6H2O
Light
carbon dioxide + water
C6H12O6 + 6O2
Light
sugars + oxygen
Slide
5 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
The Photosynthesis
Equation
Photosynthesis uses the energy of
sunlight to convert water and carbon
dioxide into high-energy sugars and
oxygen.
Slide
6 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
The Photosynthesis
Equation
Light energy
H2O
Light-Dependent
Reactions
(thylakoids)
ADP
+
NADP
Sugar
O2
ATP
NADPH
Calvin Cycle
(stroma)
Copyright Pearson Prentice Hall
CO2
+
H20
Slide
7 of 28
End Show
8-2 Photosynthesis: An Overview
Light and Pigments
What is the role of light and chlorophyll in
photosynthesis?
Slide
8 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
Light and Pigments
Light and Pigments
How do plants capture the energy of sunlight?
In addition to water and carbon dioxide,
photosynthesis requires light and
chlorophyll.
Slide
9 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
Light and Pigments
Plants gather the sun's energy with light-absorbing
molecules called pigments.
The main pigment in plants is chlorophyll.
There are two main types of chlorophyll:
• chlorophyll a
• chlorophyll b
Slide
10 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
Light and Pigments
Estimated Absorption (%)
Chlorophyll absorbs light well in the blue-violet and
red regions of the visible spectrum.
100
80
60
Chlorophyll b
Chlorophyll a
40
20
0
(nm)
400 450 Wavelength
500 550 600
650 700 750
Wavelength (nm)
Slide
11 of 28
Copyright Pearson Prentice Hall
End Show
8-2 Photosynthesis: An Overview
Light and Pigments
Estimated Absorption (%)
Chlorophyll does not absorb light will in the green
region of the spectrum. Green light is reflected by
leaves, which is why plants look green.
100
80
60
Chlorophyll b
Chlorophyll a
40
20
0
400 450 500 550 600 650 700 750
Wavelength (nm)
Copyright Pearson Prentice Hall
Slide
12 of 28
End Show
8-2 Photosynthesis: An Overview
Light and Pigments
Light is a form of energy, so any compound that
absorbs light also absorbs energy from that light.
When chlorophyll absorbs light, much of the
energy is transferred directly to electrons in the
chlorophyll molecule, raising the energy levels of
these electrons.
These high-energy electrons are what make
photosynthesis work.
Slide
13 of 28
Copyright Pearson Prentice Hall
End Show
END OF SECTION