The basic structure of chloroplast and the function of chlorophyll

1. Warm up
• Write the overall equation
for photosynthesis in
symbols.
H2O + CO2 + Light energy  C6H12O6 + O2

2. Agenda & ObjectiveAgenda & Objective
Agenda
• Warm up
• Chloroplast and
Chlorophyll notes
• Mini-lab
Objective
ID the function of the
chloroplasts
and the molecule
chlorophyll

3. Photosynthesis -
Chloroplasts and
Chlorophyll

4. Today, students will be able to:
• IdentifyIdentify the function ofthe function of
chlorophyll andchlorophyll and explainexplain
why plants are greenwhy plants are green

5. • Chloroplasts:Chloroplasts:
Where photosynthesis occursWhere photosynthesis occurs

7. • Thylakoids:Thylakoids:
–Discs inside chloroplastDiscs inside chloroplast
–Contain theContain the moleculemolecule chlorophyllchlorophyll

8. • Chlorophyll:
• a pigment that can
convert light energy
to chemical energy

9. In your head
• Chlorophyll changes ________ energyChlorophyll changes ________ energy
into _________ energyinto _________ energy
LIGHT…CHEMICALLIGHT…CHEMICAL

10. • Light energy:Light energy:
• Light is a mixture ofLight is a mixture of
different wavelengthsdifferent wavelengths
that make colorsthat make colors

11. • Chlorophyll can absorb some wavelengths ofChlorophyll can absorb some wavelengths of
light very welllight very well
Based on this graph,Based on this graph,
what color (orwhat color (or
wavelength) iswavelength) is
chlorophyll good atchlorophyll good at
absorbing?absorbing?
What color is it badWhat color is it bad
at absorbing?at absorbing?
Purple &Purple &
blueblue
RedRed
GreenGreen
In your head

12. So plants are green because…
• They are not green
• Chlorophyll absorbs
and traps all the
wavelengths (colors)
of light EXCEPT green

13. Are leaves only green? Have you ever seen
leaves that are other colors?
• Chlorophyll is green and isChlorophyll is green and is
the primary pigment inthe primary pigment in
plantsplants
• plant have other pigments asplant have other pigments as
wellwell
• This helps them get evenThis helps them get even
more light energymore light energy

14. Based on this
graph, how do
Chlorophyll a and
Chlorophyll b
compare?
In your head

15. There are many pigments in plants
• ･･ Carotone is orangeCarotone is orange
• ･･ Xanthophyll is yellowXanthophyll is yellow
• ･･ Chlorophyll A is brightChlorophyll A is bright
greengreen
• ･･ Chlorophyll B is dullerChlorophyll B is duller
greengreen
• ･･ Anthocyanin isAnthocyanin is
responsible for bright redresponsible for bright red
andand purplespurples
• ･･ Tannin is brownTannin is brown

16. Think-pair-share
• Why areWhy are
plantsplants
green?green?
The green light is reflected back, so itThe green light is reflected back, so it
is what we seeis what we see
All the other colors of light areAll the other colors of light are
absorbed by the pigment molecules,absorbed by the pigment molecules,
so we do not see themso we do not see them

18. Chromatography Mini-Lab
• Can we see the other pigments in plant cells?Can we see the other pigments in plant cells?
In other substances?In other substances?

19. Leaf Chromatography
• Cut your strip of chromatography paper so it
looks like this:
• Carefully rub your spinach leaf with a pencil
eraser or the edge of something
• This will transfer some of the leaf pigments to
the paper
• Place the paper in a cup with rubbing alcohol
• Be sure not to let the leaf rubbing touch the
alcohol

20. Cool Down
1. What pigments can you see in the leafleaf?
2. What is the function of a pigment?