Download Explain: Converting Sunlight into Sugar

 Photosynthesis
is the process by which plants
use the sun’s energy to convert water and
carbon dioxide into sugars.
 Read “Energy” p. 327 – 329
 Take Notes!
 Energy
is the ability to do work.
 Kinetic energy is the energy of motion
 Potential energy is energy that is stored due
to an object’s position or arrangement.
 Energy can be converted from one form to
another.
 Different types of energy – chemical, light,
electrical, mechanical, thermal
 Organic
molecules have a form of potential
energy called chemical energy
 Chemical energy has the potential to do work
due to the arrangement of the atoms within
the molecules.
 The rearrangement of atoms during chemical
reactions releases the potential energy, and
the energy is then available to do work.
 Photosynthesis
is the process by which plants
use the sun’s energy to convert water and
carbon dioxide into sugars.
 Light is the only source of energy for plants!
 Plants convert light energy into chemical
energy -> Photosynthesis
 Recall that light is energy
 Different colors of light have different
wavelengths and different amounts of
energy.
 Red light = low energy
 Blue light = high energy
Light is a form of energy called
Electromagnetic energy.
A
substance’s color is due to chemical
compounds called pigments.
 When light hits an object the wavelengths
can be transmitted, absorbed, or
reflected.
 Chloroplasts
contain pigments called
Chlorophyll a, Chlorophyll b, and
Carotenoids.
 Each pigment absorbs different wavelengths
of light.
 Notice
that chloroplasts absorb blue-violet
and red-orange light very well.
 The chloroplasts convert the absorbed light
energy into chemical energy.
 Why are leaves green?
 Why do leaves change colors in the fall?
 Complete Stop & Think #1-4 p. 329
 Read
“Making Carbon Compounds” p. 330-333
 Take notes!
 Read “Energy Currency of Cells” p. 333
 Take Notes.