Download Explain how an atom of carbon found in a molecule of CO2

Flying high in the sky over the coast of California is a tiny atom of carbon stuck in a tiny
molecule of CO2. For this little atom, the past two weeks have been a nightmare and the
warm breeze of Santa Monica is a welcoming reprieve. This is not the first time this little
atom went through what she did, and it will not be the last… Anyway, it was only
yesterday that she found herself inside of the liver cell of a human being in the presence
of high-energy electrons as a molecule of glucose, nervously awaiting her fate. Would
she be stuck in the human, condemned to months as part of a phospholipid, or would she
be freed to surf the Westerlies once more?
It all began two weeks ago today, when the little carbon as CO2 was a mile high
over the Galapagos Islands, riding the breeze without a care in the world. Little did she
know that in two days, a handful of photons would leave the sun on a 92 million mile
journey to Earth, and eight minutes and 20 second later their journey would be complete,
and the little carbon would be in carbon dioxide no longer. Your job is to write the story
of this carbon, and the kinetic energy of that handful of light, describing how they came
to be as one in your liver cell, and how it was let go once again into the open atmosphere.
It is completely up to you how the story goes, but details are critical (carbon cycle,
photosynthesis, cellular respiration, energy flow, etc…).
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1. Follow the energy while avoiding the use of the word “energy”
2. How is it used to combine CO2 molecules to form glucose.
3. Energy basically means the ability to accelerate.
a. you can think of light as a moving wave and things that move can hit and
accelerate other objects…like the electrons of chlorophyll.
b. You should follow the electron accelerations, which we know is all based
on AFFINITY!
i. If one molecule has a higher affinity for an electron than another
molecule, electrons can accelerate and move from the lower to the
higher affinity molecule.
ii. From chlorophyll in photosynthesis all the way down to oxygen in
cellular respiration.
4. Water to water
a. You should now realize that electrons are passed from water to
chlorophyll during the light reactions of photosynthesis and eventually
passed to oxygen during cellular respiration reforming water!!
5. Glucose as the middle man
a. electrons flow:
i. photosynthesis
1. water -> chlorophyll (excited by light)-> ETC of light
reactions -> NADPH -> glucose
a. ATP formed during light reactions
b. CO2 is used to build glucose using ATP and
NADPH from light reactions (Calvin cycle)
ii. cellular respiration
1. glucose -> NADH -> ETC of cell resp -> oxygen reforming
water
a. ATP made from ADP and P
b. CO2 left over after glucose loses electrons and ATP
is made during glycolysis and Krebs
iii. So…CO2 + ATP + NADPH gives glucose (photosynthesis)
iv. and…glucose gives CO2 + NADH + ATP (cellular respiration).
1. Of course, the NADH will transfer electrons to make more
ATP. Oxygen picks up electrons in the end forming water.
6. This is your opportunity to start building the link between photosynthesis and
cellular respiration. Glucose of course could be used in biosynthesis to build
amino acids, fatty acids, etc… rather than burn it in cellular respiration.
7. FOLLOW THE CARBONS and FOLLOW THE ACCELERATIONS