Transcript Light and Pigments

DO NOW!! 
Why do we need light?
How does light affect our ability to
live?
What would happen if the sun
burned out?
Ch. 8: Cellular Energy!!
Light and Pigments
Objectives
 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.
So what is light?
 Energy!!!
 Travels in waves
 The distance between 2 crests is a wavelength.
Wavelengths
 There are different wavelengths for each type of light.
 The shorter the wavelength, the higher the energy!!
Visible Light
 The light we see is called visible light.
 ROYGBIV…
 https://www.youtube.com/watch?v=O0PawPSdk28
Which color has…
 The shortest wavelength?
 The longest wavelength?
 What is wavelength measured
in?
Why do we see COLORS?
The color you see is the color being
reflected.
*All other colors are being absorbed.
 So why do black shirts get hot in the
sun??
So ponder this…
Why do plants appear to be green?
Why are Ms. Finn’s glasses blue? And the sky?
Do Now!! 
 What specifically distinguishes each type of
light?
 Which color in the visible spectrum has the
highest amount of energy? The lowest?
 Why can’t a person have x ray vision?
Objectives
 To define pigments
 To identify the pigments in plants
 To complete an introduction to photosynthesis
Pigments
 Chemical compound that gives a substance it’s color
 They can absorb and reflect certain wavelengths
 Pigments are everywhere (clothes, flowers, etc.)
Why do you think pigments are necessary for
photosynthesis?
Examples of plant pigments
 Principal pigments:
1. Chlorophyll- reflects green
2. Carotenoids- red, orange or yellow
3. Xanthophylls- red and yellow
4. Anthocyanins- red to blue
anthocyanin
Do Now!! 
 Which has more energy, short or long
wavelengths?
 Why does something green appear to be
green?
 What is the main pigment in plants?
Objectives
 To define pigments
 To identify the pigments in plants
 To discuss different types of energy and the
laws of thermodynamics
Chlorophyll
Green pigment that
aids in photosynthesis.
Found in leaves and
appears green.
Allows plant to capture
light.
Think- Pair- Share
 Use the absorption
spectrum for
chlorophyll…
What colors does
chlorophyll absorb?
What colors does it
reflect?
What color does it
appear to us?
Carotenoids
 Orange pigment found in most leaves.
 Absorbs additional light
Review!
 What type of light do we see?
 What is a pigment?
 What are the names of the pigments in leaves?
 Why are pigments important in photosynthesis?