Transcript Light

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Why do we need light?
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How does light effect our ability to live?
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What would happen if the sun burned out?
Section 8.2
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To understand the different types of light and
their wavelengths.
To be able to explain how pigments enable
us to see different colors.
To determine the role of light and pigments
in photosynthesis.
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Energy!!!
Travels in
The distance between 2 crests is a
wavelength.
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There are different wavelengths for each type
of light.
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The light we see is called visible light.
ROYGBIV…
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The shortest wavelength?
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The longest wavelength?
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What is wavelength measured
in?
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The color you see is the color being reflected.
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*All other colors are being absorbed.
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Why do plants appear to be green?
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Why is the sky blue?
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Chemical compound that gives a substance
it’s color
They can absorb certain wavelengths
Pigments are everywhere (clothes, flowers,
etc.)
Ex: Chlorophyll, Carotenoids.
Why do you think pigments are necessary for
photosynthesis?
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Green pigment that aids in photosynthesis.
Found in leaves and appears green.
Allows plant to capture light.
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Use the absorption
spectrum for
chlorophyll…
◦ What colors does
chlorophyll absorb?
◦ What colors does it
reflect?
◦ What color does it
appear to us?
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Orange pigment found in most leaves.
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Usually hidden by chlorophyll.
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What type of light do we see?
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What is a pigment?
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What are the names of the pigments in
leaves?
Why are pigments important in
photosynthesis?
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http://video.google.com/videoplay?docid=3537053342610184162&ei=PehmS6uzD5mY
qwLjn929CA&q=light+and+pigment+in+pho
tosynthesis&hl=en&view=3#docid=7377788683046188633
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What does a plant need to live?
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How do plants help US live?