Narcissus Flowers
http://highered.mcgraw-hill.com/sites/0078617022/student_view0/brainpop_movies.html#
1. Photosynthesis
2. Photosynthesis in
Inspiration
3. Using Inspiration
4. References
Photosynthesis
• Photosynthesis
transforms solar light
energy trapped by
chloroplasts into:
-chemical bond energy
of carbohydrates.
Autotroph vs. Heterotroph
• Organisms acquire organic molecules through either:
1. Autotrophic Nutrition
(Auto = self; troph = feed):
•Producers
•Photoautotrophs and
chemoautotrophs
•ex: plants, algae, some
prokaryotes
2. Heterotrophic Nutrition
(Heteros = other; troph =
nutrition):
•Consumers
•ex: animals that eat plants or
other animals, decomposers.
Chloroplasts
• The site where
photosynthesis occurs
• Located in leaves
• Chlorophyll is located in
chloroplasts
• Chlorophyll is the green
pigment that gives
photosynthetic organisms
its color.
Chloroplast
Chloroplasts
Outer Membrane
Inner Membrane
Thylakoid
Grana
(singular
granum)
Stroma
Chloroplasts
Outer Membrane
Inner Membrane
Stroma
Grana
(singular
granum)
•Chlorophyll is found in the
thylakoid.
Thylakoid
•Converts light energy to
chemical energy (PSI & PSII).
Chloroplasts
Outer Membrane
Inner Membrane
Stroma
Thylakoid
Grana
(singular
granum)
Grana is stacks of thylakoids
in the chloroplast
Chloroplasts
Outer Membrane
Inner Membrane
•Stroma is the fluid outside
the thylakoids.
Stroma
Thylakoid
Grana
(singular
granum)
•Uses chemical energy to
convert carbon dioxide to
sugar (Calvin Cycle)
Chloroplasts
Outer Membrane
Inner Membrane
Stroma
Thylakoid
Grana
(singular
granum)
Chloroplasts are
surrounded by
two membranes
Chloroplasts
Chloroplasts are
surrounded by
two membranes
Outer Membrane
Inner Membrane
•Stroma is the fluid outside
the thylakoids.
Stroma
Grana
(singular
granum)
•Chlorophyll is found in the
thylakoid.
Thylakoid
•Converts light energy to
chemical energy (PSI & PSII).
•Uses chemical energy to
convert carbon dioxide to
sugar (Calvin Cycle)
Grana is stacks of thylakoids
in the chloroplast
Photosynthesis Pathway
Overall equation:
6CO2 + 6H2O + light energy
C6H12O6 + 6O2
Splitting of Water:
O2 released by plants comes from the splitting of
water, not from CO2.
Plants split water as a source of hydrogen and release
oxygen as a by-product.
Light Reactions Overview
Light (Dependent) Reactions
= Convert light energy to
chemical bond energy in ATP
and NADPH (energy
capturing rxns.)
1. Occurs in the
thylakoid membrane.
Two Types:
1. Cyclic (generates
ATP and uses PS I)
2. Noncyclic
(generates ATP and NADPH
and uses PSI and PSII).
Light Independent Reactions Overview
Light Independent Reactions
= Calvin cycle which makes
sugars (synthesis rxns).
1. Occurs in the stroma of
the chloroplast.
2. Calvin Cycle (3 Parts)
1.Incorporates
atmospheric CO2 into existing
organic molecules (carbon
fixation)
2. CO2 Reduction
3. Regeneration of
RUBP
Solar Energy
•Solar radiation is described in terms
of its energy content and its
wavelength.
•The electromagnetic spectrum is
the range of types of solar radiation
based on wavelength.
•Short wavelength = higher energy
content and
•Long wavelength = lower energy
content.
Solar Energy
•A graph of wavelength versus
rate of photosynthesis is an
action spectrum.
•Shows effectiveness of
different wavelengths of
visible light for driving
photosynthesis.
•Accessory Pigments expand the range of wavelengths available
for photosynthesis.
- chlorophyll b: yellow-green pigment
-chlorophyll a: slightly diff. absorption spectrum
-carotenoids: yellow-orange hydrocarbons
Photosystems
•
Pigments are assembled into
photosystems located within the
thylakoid membrane.
•
A photosystem absorbs solar energy and
generates high energy electrons.
•
Each photosystem is composed of:
-Antenna complex
-Reaction-Center chlorophyll
-Primary electron acceptor
•
There are 2 types of photosystems:
1. Photosystem I
2. Photosystem II
P700
P680
Cyclic Electron Pathway
•Simplest pathway - generates ATP and no NADPH or
Oxygen. It uses only PS I.
•It is cyclic because excited electrons that leave from
the chlorophyll a at the reaction center return to the
reaction center.
•Cyclic supplements the ATP supply required for the
Calvin cycle and other metabolic pathways.
•Some photosynthetic bacteria use cyclic only-may
have evolved early.
•May be utilized only when CO2 is in limited supply.
Cyclic Electron
Pathway
•Photons are absorbed by PS I.
•Reaction Center releases excited
electrons to the electron acceptor.
•Electrons are passed to Ferredoxin.
•Electrons travel down Electron transport System (ETS).
-as they move down ETS they pass from higher to lower
energy level
-energy released is stored in form of H+ gradient.
-When H+ ions flow down their electrochemical gradient
through ATP synthase complesxes, ATP is produced.
(Chemiosmosis)
NonCyclic Electron Pathway
•Both PS I and PS II are
used.
•NADPH and ATP are
produced.
•Occurs in the thylakoid
membrane.
•Produces Oxygen.
•Electrons move from
water through PSI/PSII
and then on to NADP+ •PS II takes replacement electrons
from water, which splits, releasing
O2 and H+ ions - Photolysis.
NonCyclic Electron Pathway
•PS II absorbs light energy and
boosts electrons.
•Electrons are passed to the
primary electron acceptor and
then to the ETS.
•Electrons lose potential energy
(and produce ATP) as they
move down the ETS and arrive
at the PS I.
•Light excites electrons in PSIthese excited electrons do not
return to the rxn center but are
stored in NADPH.
•Again in PSI, excited electrons are passed to an electron acceptor and
then to ferredoxin.
•Ferredoxin passes the electrons to NADP+ to produce NADPH
Chemiosmosis
•Chemiosmosis is a coupled
reaction.
•The thylakoid space acts as a
reservoir for H+ ions; each time
water is split, two H+ remain.
•Elecrons move carrier to carrier,
giving up energy to pump H+ from
stroma into thylakoid space.
•Flow of H+ from high to low concentration across thylakoid
membrane provides energy to produce ATP from ADP using
the ATP synthase enzyme.
•In Photosynthesis this process is called photophosphorylation.
•ATP is produced on the outside of the thylakoid, depositing it
in the stroma for use in the Calvin Cycle.
Light Independent Reactions
(Dark Reactions)
• Light is not directly required,
CO2 is required.
• The Calvin Cycle uses ATP
and NADPH from the light rxns
to convert CO2 to CH2O. (CO2
is reduced)
• CO2 reduction occurs in the
stroma of a chloroplast.
• Calvin Cycle has 3 Parts.
Calvin Cycle:
Part 1
Carbon
Fixation
• CO2 fixation is the attachment of CO2 to an
organic compound.
• RuBP is the 5 carbon molecule that combines
with CO2.
• Enzyme RuBP carboxylase (rubisco) speeds
reaction.
• The product of this reaction is an unstable 6
carbon intermediate molecule
Calvin Cycle:
Part 2
Reduction of
CO2
• 6 carbon intermediate immediately breaks down
into 2 PGA molecules (3-phosphoglycerate C3).
• Each of two PGA molecules undergoes reduction
to PGAL in two steps.
• Light dependent reactions provide NADPH
(Electrons) and ATP (energy) to reduce PGA to
PGAL (G3P).
• It takes 2 PGAL to make 1 Glucose, 6 turns of
the Calvin Cycle.
Calvin Cycle: Part
3
Regeneration of
RuBP
• Every 3 turns of the Calvin Cycle, 6 PGAL are produced.
• 5 PGAL are used to regenerate 3 RuBP and 1 is used to
build carbohydrate.
• It takes 2 PGAL to build 1 Glucose.
• PGAL is the raw material that can be used to synthesisze
other carbohydrates as well
• To make this glucose 18 ATP and 12 NADPH are used.
Modes of Photosynthesis
• The Calvin Cycle, as discussed here, is also called C3
photosynthesis.
• This is because the 1st molecule created (PGA) is a 3
carbon molecule.
Modes of Photosynthesis
Photorespiration
• A metabolic pathway that consumes
oxygen, evolves CO2, produces no
ATP and decreases photosynthesis.
•Occurs because active site of rubisco can accept O2 as well
as CO2
•When O2 concentration in a leaf’s air spaces is higher than
CO2, rubisco accepts O2 and tranfers it to RuBP.
•Whether photorespiration is beneficial to plants is not known.
•If photorespiration could be reduced in agricultural plants,
crop yields and food supplies would increase.
•Photorespiration is fostered by hot, dry, bright days when
plants don’t open stomata to reduce water loss.
Modes of
Photosynthesis
• Sometimes PGA (a 3 carbon
molecule) is not the first
molecule created.
• C4 plants fix CO2 by forming
a C4 molecule prior to the
involvement of the Calvin
cycle.
• CAM plants fix CO2 by
forming a C4 molecule at
night when stomates can
open without loss of water.
**These alternate forms are adaptations to
minimize photorespiration.
• In C3 plants, mesophyll cells contain
chloroplasts arranged in parallel layers.
• In C4 plants, bundle sheath cells as well as
mesophyll cells contain chloroplasts.
• In C4 leaves, mesophyll cells are arranged
concentrically around the bundle sheath
cells.
• C4 plants use the enzyme PEP carboxylase (PEPcase) to
fix CO2 to PEP; end product is oxaloacetate (OAA-a 4
carbon molecule).
• OAA is then converted to malate and the malate is shuttled
to bundle sheath cells. Here malate is converted to
pyruvate and CO2.
C4
•Pyruvate is then shuttled a
back to meophyll cells where
Photosynthesis one 1 ATP is required to convert
the pyruvate back into PEP.
•The overall effect is to move
CO2 from mesophyll cells to
bundle sheath cells.
C4 Photosynthesis
• The purpose of moving CO2 to
bundle sheath cells is to
increase efficiency of
photosynthesis.
• Very little oxygen reaches
bundle sheath cells so when
malate delivers CO2 to them
rubisco begins Calvin cycle.
• Because little oxygen is present
here, CO2 can be fixed without
competition from O2.
•In hot, dry climates, net • Little photorespiration takes
photosynthestic rate of C4
place and photosynthesis is
plants is 2-3 times that of
more efficient.
C3 plants.
Modes of Photosynthesis
CAM Plants
• CAM = crassulacean acid metabolism.
• Exists in succulent plants adapted to very arid conditions.
These plants open their stomata primarily at night and
close them during the day (opposite of most plants)
• Conserves water during the day but prevents CO2 from
entering the leaves.
• When stomata are open at night, CO2 is incorporated into a
variety of organic acids.
CAM
Plants
• Organic acids are stored in
vacuoles until morning when
the stomata close.
• During the day, light reactions
supply ATP and NADPH for the
Calvin Cycle.
• At this time, CO2 is released
from the organic acids and
used to make sugars.
A Review of Photosynthesis
• On a global scale, photosynthesis makes
about 160 billion metric tons of
carbohydrate per year.
• No other chemical process on Earth is more
productive or is as important to life.
• Photosynthesis transforms light energy to
chemical bond energy in sugar molecules
A Review of Photosynthesis
• Light reactions capture solar energy and use it to produce
ATP and transfer electrons from water to NADP to form
NADPH.
• The Calvin cycle uses ATP and NADPH to fix CO2 and
produce sugar.
• Photorespiration
can reduce
photosynthetic yield
in hot dry climates.
A Review of Photosynthesis
• Alternate methods of carbon fixation
minimize photorespiration.
• C4 plants spatially separate carbon
fixation from the Calvin Cycle
• CAM plants temporarily separate carbon
fixaton from the Calvin Cycle.
• Regardless of whether the plant uses C3,
C4 or CAM pathway, all plants use the
Calvin Cycle to produce sugar from
CO2.
Using Inspiration
Opening Inspiration:
1. Go to START, then to PROGRAMS, then to Inspiration.
2. In Inspiration go to File menu.
3. Choose Save.
4. Save file as: “your last name_photosynthesis”
Using Inspiration
Making your graphic organizer with Inspiration.
5. Click on the symbol with “Main Idea.”
6. Type in Photosynthesis. This is your main idea.
Using Inspiration
7. Now click on Rapid Fire located at the top menu bar.
Using Inspiration
8. Type a subtopic of Photosynthesis and then hit return. This will give
you another circle.
9. Continue to type in different subtopics you would like to address.
10. Click on one of your subtopics and click on the Rapid Fire button.
This will allow you to create another link off that subtopic.
Using Inspiration
Adding pictures to your graphic organizer from Inspiration Library.
11. Highlight the circle you would like to change.
12. Go over to the menu bar on the left with different symbols.
13. Click on the arrow at top that will show different types of symbols.
14. Chose one and click on it. This will change your symbol.
Using Inspiration
Adding pictures to your graphic
organizer from the Internet.
15. Open up Internet Explorer and go to
Google Images.
16.Type in key word and click search.
17. Find Image and save to desktop.
18. Don’t forget to name Image.
19. Click back on Inspriation.
20. Go to Edit.
21. Scroll down to Insert Graphic.
22. New window will come up and
click on desktop.
23. Find image and click return.
SAVE YOUR WORK WHEN FINISHED!
1. http://nakahara.ac/flower/flower-large/narcissus.jpg
2. http://sunflower.bio.indiana.edu/~rhangart/plantmotion/ flowers/flower.html
3. http://www.free-clipart.net/main.html
4. www.rosswarner.com/2988.html
5. www.madsci.org/posts/ archives/1065583527.Zo.1 .jpg
6. http://35.9.122.184/images/10-Photosynthesis/10-02-Chloroplast-NL.gif
7. http://www.ualr.edu/~botany/chloroplast.jpg
8. http://www.photo.net/philg/digiphotos/200108-nikon995-macro/orchid-straight.half.jpg
9. http://35.9.122.184/images/10-Photosynthesis/HTML/ source
/37.html&h=600&w=528&sz=40&tbnid\
10. http://www.msu.edu/course/lbs/145/smith/s02/graphics/ campbell_10.16.gif
11. bio.winona.msus.edu/ berg/241f99/Labs/Lab9-PS.htm
12. Kelsey Prock
13. Tina Doss