🎵 Luyện Nghe Bài Hát: Photosynthesis - Glenn Wolkenfeld

 Photosynthesis
  Cyclic Electron Flow and The Calvin Cycle
 Amusical Lecture by Glenn 
 
 Thanks for joining us for  Two,
 Wher more ‘bout photosynthesic waits  you.
 We last  how plant cells create, O¬¬2, ATP, and NADPH.
 Now we’ll  with a twist on the light reactions,
  cyclic flow, we’ll see how it happens.
 Then we will investigate how the Calvin Cycle  carbohydrate.
 
  I, Cyclic Electron Flow)
 Non –  flow is also called the “Z – scheme” Put Z on its site and see what I mean.
 Electrons rise in energy then  and rise again.
 Making ATP and NADPH  friends.
 A variation on this is  flow.
 Which makes  no NADPH or O.
  flow results from the Calvin Cycle’s needs.
 It uses  NADPH than ATP.
 NADPH buildup  the repercussion, of inhibiting NADP+ reduction.
 ‘cause NADPH clogs up 
 Keepping NADP+ from moving into 
 So electrons don’t go  NADP+.
 They’re  stuck like a pimple’s pus.
 Where can they go from 
 Nature evolved  a place to flow.
 A shunt pathway  them to the ETC.
 I’m talking ‘bout the  in PS II tou see.
 These  alectrons flow and release energy.
 Which as you know is used  synthesize ATP.
 
 ( Part  Calvin Cycle)
 Now it’s  to learn the cycle named for Calvin.
 Which  in the fixation of carbon.
 Consider that each carbon in your bones, blood and 
 Was  in a CO2 in the air.
 The Calvin  has three parts.
 Fixation of carbon is  it starts.
 The molecules produced rae  reduced.
  reduction is the key thing that happens in part 2.
 Part 2 is the payoff as  will see.
 It produces  G3P
 A reduced molecule  lots of energy.
 And a starting point for all the molecules  cells need.
 Part  sets up conditions for the cycle’s start.
 By recreating what’s at the  heart.
  (Ribulose Bisphosphate), a five carbon molecule that seems to apparate.
 ‘Cause RuBP’s  the cycle’s start.
 Then reappears at the very last 
  role of RuBP at the start and end.
 Is  this is a cycle like the one named Krebs.
 The cycle’s inputs are know to you: NADPH and  and CO2
 Fixation  carbon is catalyzed by RuBP Carboxylase Enzyme
 This enzyme’s nickname you  know.
 Sounds like  cookie maker: it’s RUBISCO.
 An enzyme so old it was  here,
 Before O2  in the air.
 The CO2 enters through leaf stoma, diffusing  the leaf and arriving at the stroma.
 There RuBisCO grabs it in its active site, and squeezes it with RuBP 
 RuBP has carbons five, it has two  one on each side.
 When CO2 combines with RuBP it makes a  carbon compound you won’t see.
 It instantly dissociates  two 3 – phosphoglycerates,
 Each with three carbons and  phosphate.
 Each gets phosphorylated  bisphosohoglycerate.
 Phosohorylated  that each receives aphosphate group from ATP.
 This phospharylation, is followed by 
 And you know  an enzyme with the function.
 Of taking electrons and H from NADPH and adding them to to 
  off a phosphate for Glycealdehyde – Phosphate.
 A starting  for compounds like carbohydrates.
 
 (Part III:  Cycle, conclusion)
 Glyceraldehyde- 3  phosphat, known as G3P,
  a product cells harvest, and I hope you see,
 how light reactions  and ATP,
 are needed to fix  and make organic energy.
 And to complete the cycle  must now regenerate.
 The starting point  Calvin Cycle ribulose bisphosphate.
 The intermediates involved  taking G3Ps,
 And recombining them  RuBPs.
 Are too  for freshman biology.
 You can get the details when you get yors Ph. 
 But know for now that to get 3 RuBPs from 5  cost 3 ATPs!
 
 (Part IV: 
 Now this journey ends  its emphasis,
 On the reaction of 
 For over four billion years it’s been the  chains basis.
 In fossils from that era you can see  traces,
  tiny cells with prokaryotic form.
 Stromatolites that lived in waters 
 Through photosynthesis they transformed  planet,
 So aerobic life can  upon it.
 And so evolved sentient beings who  analyze,
 How photoautotrophs can 
 You could say that photosynthesis gave  to codiyions for cons ciousness on Planet Earth!