Photosynthesis Rap

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ever wonder why a plant doesn’t need to eat
makes food from the sun, that you can’t beat
uses water during this process too
creates sugar from light and CO2
now it’s got energy to grow
called photosynthesis, you didn’t know
does the opposite of what we do
plants take in carbon dioxide and release O2
what makes a plant green? I’m glad you asked
photosynthesis takes place inside the chloroplast
plant cells can contain 100 or only one
filled with chlorophyll, where this process runs
chemistry of photosynthesis is mad easy bro
start with 6CO2 and 6H2O
add sunshine and chlorophyll to the mix
end up with C6H12O6
that’s sugar, food or glucose
plant eats it for breakfast like we eat toast
also makes 6O2 that we need
6 molecules of oxygen so we can breathe
studying the chloroplast won’t put you in a coma
inside is a fluid-filled region called the stroma
there you find the grana look like stacks of coins
what make up the grana are thylakoids
that’s where chlorophyll makes it all happen
two stages of photosynthesis: light and dark reactions
light reactions use the sun’s photons you see
make NADPH and ATP
happens in the chlorophyll reaction centers
antenna pigments gather the light as it enters
these molecules bounce energy to Photosystem 1
or Photosystem 2, depends on the wavelength son
PS 2 absorbs light at 680 nanometers
PS 1 absorbs light at 700 nanometers
depends on the chlorophyll type, ain’t tryin’ to be shady
PS1 is P700 and PS 2 is P680
noncyclic photophosphorylation you see
uses PS2 and PS1 to make ATP
photon is captured, to P680 it goes
activate electrons, to primary acceptor they flow
how’d it get electrons, photolysis is how
P680 splits water now
takes 2 electrons and makes H and O2
that’s lots of O2 for me and you
next electrons go down transport chain son
arrive at P700 or PS1
hydrogen ions are pumped into the thylakoid
then move through ATP synthase boy
ATP is produced by ADP and phosphate
photon hits PS1 a little bit late
two electrons travel through another chain
NADP becomes NADPH with the 2e- gain
less efficient method when there’s no more NADP
no NADPH produced only ATP
proton is captured, excites two electrons
go down the chain, then back to Photosytem 1
this is called cyclic phosphorylation
cyclic because electrons go in a cycle son
NADPH is not made in it
no electrons from water because it’s not split
all light reactions occur in the thylakoids
where all these pigments are, filling the void
rest of the stuff occurs in the stroma, ain’t this fun
now let’s rap about the dark reactions
energy is stored to make the food you see
in the NADPH and ATP
but it needs carbon for the 6C’s
sugar, glucose and it gets it from  me
how does it get it, well gets it from you too
it’s the stuff we breathe out in the form of CO2
carbon dioxide is turned into carbs
called carbon fixation, lets a plant live large
CO2 enters the Calvin cycle now
need to know a li’l chemistry let’s break it down
CO2 has one carbon, combines with 5
ribulose bisphophate with 6C’s comes alive
RuBP carboxylase makes the reaction strong
that’s what an enzyme does, it pushes it along
what enzymes do, they make things happen
proteins that control living things while your rappin’
we’ll get more into enzymes in another joint
let’s get back to the original point
say 3 RuBP’s combine with CO2’s they found
creating 3 unstable 6C compounds
forms 6 phosphoglycerates when it breaks down
or 6 PGA’s that’s 6 3C compounds
from 6 ATP’s it steals a phosphate
now you got 6 bisphosphglycerates
next take 6NADPH, well
it makes 6 glyceraldehyde 3-phosphate (PGAL)
these joints contain lots of energy
will all that NADPH and ATP
5 PGAL recombine to form 3 RuBP
are you still with me, total C’s are 15
PGAL is used to make C6H12O6
PGAL has only 3 C’s but glucose has 6
I tell ya its true, rappin’ from the heart
I know you can get it, ya seem pretty smart
ya want  me to tell ya, aight I’ll be nice
get 2PGAL from going through the Calvin cycle twice
that’s 2 times three carbons, now do ya get it
6 Carbons make glucose, how does that sit
too much info about plants, is that what’s the matter
say this rap a couple times you’ll get the whole enchilada
ya see without the sun all animals would die
the original G of all of us that ain’t no lie
so next time you see it say thank you bro
for taking care of me and all the peeps I know