Bacteria to Plants
Chapter 4 Introduction to Plants
Section 2 Photosynthesis and Light
Key Concepts:
1. What happens when light strikes a green leaf?
2. How do scientists summarize the process of photosynthesis?
Key Terms:
• Transmission
• Reflection
• Absorption
• Accessory Pigment
Light and Plants
Light does three (3) things
 Transmission- The
process in
which light passes through an
object
Reflection- The process in
which light bounces off of an
object
Absorption- The process in
which light is taken in by an
object
Light and Plants
Plant Pigments
 Chlorophyll
 The most abundant pigment in
leaves
Absorbs most of red and blue light
 Green light is reflected causing
chlorophyll, and the leaves it is in, to be
green.
Accessory Pigments- Any
pigment other than chlorophyll
found in plant cells
 Orange, Yellow
 Masked because there is so
much more Chlorophyll
Photosynthesis
1. Capturing Energy
 Photosynthesis begins
when light is absorbed
by a plant’s chloroplasts
 Uses this energy to
power the food making
process
2. Chemistry
 Use carbon dioxide gas
and water to feed the
reaction.
 Sugar and Oxygen gas
are formed.
Photosynthesis
Photosynthesis Chemical Equation!
H2O + CO2 ------ C6H12O6 + O2
Water
Plus Carbon Dioxide Yields
Sugar
and Oxygen
Chapter 4 Introduction to Plants
Section 2 Photosynthesis and Light
1. What happens when light strikes a green leaf?
2. How do scientists summarize the process of photosynthesis?
Section Review on p. 119