Where does almost all energy come from for Earth?

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Where does almost all energy come from for Earth?
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(No Transcript)
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Do you have energy within your body?
Potential Energy stored energy (ATP molecules,
Carbohydrate, Proteins and Lipids)
Kinetic Energy energy in motion (breaking down
ATP to ADP, or any other molecule)
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JQ Why do you think plants are green for most of
the year, instead of red, orange or yellow?
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Whats in Sunlight?

• A prism, like the one shown below, is an object
  designed to alter light as it passes through it.
• BE EXTREMELY CAREFUL WITH ALL THE EQUIPMENT
• Obtain a prism and a spectroscope,
• Try to get the prism and spectroscope to separate
  white light into colors (might have to go near
  window)
• Make a list of all the colors your prism
  produces, and take a picture if you can.

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Use your textbook to read about photosynthesis,
the process that supplies all ecosystems with
energy. Complete the note sheet as you go.
Link to Note Sheet
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What is photosynthesis?
CO2 H2O Sunlight ? O2 C6H12O6
The process of converting carbon dioxide, water,
into oxygen and glucose. Sunlight supplies the
energy for this process.
The most important biological process on the
planet )
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Who does photosynthesis?
Plants, some bacteria, some protists, and even
some (one known) animal can perform
photosynthesis.
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Journal Question
What would happen if all of the plants on earth
suddenly died today? Explain.
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Where does it occur?
For plants, protists (and that one animal) it
occurs inside the cells, there are special
structures called chloroplasts. They are what
make photosynthetic organisms green. Bacteria
dont have organelles, they perform it on their
plasma membrane
One chloroplast
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Where does it occur (cont)?

• Each chloroplast is covered in 2 bilayers, and
  contain the following
• Granum (stacks of thylakoids)
• Thylakoids (contain chlorophyll, light reactions
  occur on the membrane of these)
• Stroma liquid outside of the granum

Silly way to remember how the chloroplast is
organized If the Chloroplast is the
Company, Then the Grana (plural of granum) are
the garages, And the Thylakoids are the Trucks
One chloroplast
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How does it occur (overview)?
Link to time lapse
Link to song
The green pigment inside chloroplasts, called
chlorophyll, absorb light energy from the sun,
and the cell can use the energy to covert CO2 and
H2O into sugar (glucose). Plants also have other
pigments that can help.
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How does CO2, O2, and Water get in and out of a
plant?

1. Plants have pores on the bottom of their leaves
   called stomata

They open and close to let Oxygen (O2) and Carbon
dioxide (CO2) in and out. Water can leave
through them as well. Water is taken into plants
through roots.
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How does it occur (detailed)?

• Stage 1 Light reactions
• What happens here H2O Light energy ? ATP
  NADPH O2

Link to animation
2. Light energizes, or excites, electrons in
chlorophyll molecules in photosystem II (protein
with pigments attached), and electrons leave
chlorophyll and travel down the electron
transport chain (ETC), which is a series of
proteins that transfer electrons
3. Electrons lose energy as they travel through
ETC, and that energy used to move protons (H)
from stroma into thylakoid space (against
concetration gradient)
H
H
H
H
H
H
H
H
H
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How does it occur (cont)?

• Stage 1 Light reactions
• In photosystem I (after photosysten II), light
  excites electrons, which travel down another ETC.

2. As electrons lose energy through photosystem
I, proteins in the ETC help a chemical reaction
that combines NADP , protons (H), and the
electrons to produce NADPH, a high-energy
carrier molecule that is used in Stage 2 of
Photosynthesis
H
H
H
H
H
H
H
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How does it occur (cont)?

• Stage 1 Light reactions
• The reason that plants need water is so that
  water can be split electrons from water
  molecules are used to replenish those lost by
  Photosystem II (Water is split into 2H, O, and
  electrons)

2. There is a high concentration of protons (H)
accumulating inside the thylakoid. The H build
up inside as they are pumped in during ETC, and
as water is split.
3. H moves down its concentration gradient
through ATP synthase, a protein in the thylakoid
membrane that makes ATP from ADP. This is called
Chemiosmosis
H
H
H
H
H
H
H
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Photosynthesis Recap for Phase 1
CO2 H2O Sunlight ? O2 C6H12O6
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How does it occur (cont)?

• Stage 2 Dark Reactions (Calvin Cycle)
• What happens here CO2 ATP NADPH ? C6H12O6
  (Glucose)

2. CO2 moves through stomata (pores in bottom of
leaves) from atmosphere, diffuses through cell
membrane and through thylakoid membrane into the
Stroma. (what type of diffusion occurs here?)
3. CO2 undergoes a series of chemical reactions
with other molecules to form C6H12O6 (Glucose) .
Energy from the ATP and NADPH are used to power
the chemical reactions. NADP and ADP are sent
back to light reactions
4. When CO2 is used in chemical reactions in
order to form molecules inside our body, like
glucose, it is called Carbon Fixation.
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Summary of Photosynthesis (cont)?
Both the light reactions and dark reactions
are occurring at the same time within the
chloroplast, but there are differences.
Complete the chart to quiz yourself on some of
the basics of photosynthesis
Light Reactions Dark Reactions / Calvin Cycle
1. Where does it occur?
2. What are the reactants (chemicals that go into the process)
What are the products (chemicals that are made from the process
Key players involved?
Does this stage produce usable energy or deplete usable energy?
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Active Class Discussion
Your Homework is to come up with 10 questions
containing the word Attraction, and to
finish the chart on the previous slide
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Can we capitalize on photosynthesis?
Link to leaf-inspired solar panel
For a very long time, nature has influenced
mankinds technology.
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So then, why are plants green?
A. Which colors do chlorophyll absorb best?
Absorption Spectrum for Photosynthetic pigments
Plants are green because it helps them absorb
blue and red light, which are the most
energy-efficient colors to absorb from our sun.
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Alien Plants?
Based on the colors of the plants on Pandora,
how similar is the sunlight they receive, and
their absorption spectrum is to the plants on
earth?
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Wrap-Up Photosynthesis

• What is it?
• Who Does it?
• Where does it happen?
• 4. Why is photosynthesis so important to life on
  earth?

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How do plants manage all this?

• Click on
• Woodland timelapse
• Meat-eating plant
• Parasitic plant

After all, they are barely living, right?