🎵 Luyện Nghe Bài Hát: Photosynthesis - Glenn Wolkenfeld

 Photosynthesis
 Non Cyclic Electron Flow  The Calvin Cycle
 Amusical Lecture by Glenn 
 
 Thanks for joining  for Episode Two,
 Wher more ‘bout photosynthesic waits  you.
  last saw how plant cells create, O¬¬2, ATP, and NADPH.
 Now we’ll start with a twist  the light reactions,
 Called cyclic flow, we’ll see how  happens.
 Then we  investigate how the Calvin Cycle makes carbohydrate.
 
 (Part I,  Electron Flow)
 Non – cyclic flow is also called the “Z – scheme” Put Z on its site  see what I mean.
 Electrons rise in energy  fall and rise again.
 Making  and NADPH my friends.
 A variation on this is  flow.
 Which makes ATP, no  or O.
 Cyclic flow results from the Calvin  needs.
 It  less NADPH than ATP.
 NADPH buildup has the  of inhibiting NADP+ reduction.
 ‘cause NADPH clogs  reductase.
 Keepping NADP+ from moving  place.
 So electrons don’t  to NADP+.
  clogged, stuck like a pimple’s pus.
  can they go from P700?
 Nature evolved them a place to 
 A shunt pathway moves them  the ETC.
 I’m talking ‘bout the one in PS II  see.
 These energized alectrons flow and  energy.
 Which as you know is used  synthesize ATP.
 
 ( Part II: Calvin 
 Now it’s time  learn the cycle named for Calvin.
 Which results in the  of carbon.
 Consider that each  in your bones, blood and hair,
 Was once in a  in the air.
 The Calvin  has three parts.
 Fixation  carbon is how it starts.
 The molecules produced rae  reduced.
 ‘cause reduction is the key thing that happens in  2.
  2 is the payoff as you will see.
 It  molecule G3P
 A  molecule with lots of energy.
 And a starting point for all  molecules that cells need.
 Part 3 sets  conditions for the cycle’s start.
 By recreating what’s  the cycle’s heart.
 RuBP (Ribulose Bisphosphate), a five carbon molecule that seems  apparate.
 ‘Cause RuBP’s at  cycle’s start.
 Then reappears at the very  part.
 The role of RuBP at the start and 
 Is why this is a cycle  the one named Krebs.
 The cycle’s inputs are know to you:  and ATP and CO2
 Fixation  carbon is catalyzed by RuBP Carboxylase Enzyme
 This enzyme’s nickname  should know.
 Sounds like  cookie maker: it’s RUBISCO.
 An  so old it was already here,
 Before O2  in the air.
 The CO2 enters through  stoma, diffusing through the leaf and arriving at the stroma.
 There RuBisCO grabs  in its active site, and squeezes it with RuBP tight.
 RuBP has carbons five,  has two phosphates, one on each side.
 When CO2 combines with RuBP it makes a  carbon compound you won’t see.
 It instantly  into two 3 – phosphoglycerates,
 Each with three carbons and one 
 Each gets phosphorylated  bisphosohoglycerate.
 Phosohorylated means that each receives  group from ATP.
  phospharylation, is followed by reduction.
 And you know there’s an enzyme  the function.
 Of taking  and H from NADPH and adding them to to bisphosphoglycerate.
 Take off a phosphate for Glycealdehyde  Phosphate.
 A starting  for compounds like carbohydrates.
 
 (Part III: Calvin  conclusion)
 Glyceraldehyde- 3  phosphat, known as G3P,
 as a product cells harvest, and  hope you see,
  light reactions NADPH and ATP,
 are needed to fix CO2 and make  energy.
 And  complete the cycle we must now regenerate.
 The starting  of Calvin Cycle ribulose bisphosphate.
 The intermediates  in taking G3Ps,
 And  them into RuBPs.
 Are too much  freshman biology.
 You can get the details when you get  Ph. D.
 But know for now that to  3 RuBPs from 5 G3Ps cost 3 ATPs!
 
  IV: Conclusion)
 Now this journey ends whit  emphasis,
 On the reaction  photosynthesis.
 For over four billion years it’s been  food chains basis.
 In fossils from that era you can  the traces,
 Of tiny cells with prokaryotic 
 Stromatolites that  in waters warm.
 Through photosynthesis  transformed our planet,
 So aerobic life  live upon it.
 And so evolved  beings who can analyze,
 How photoautotrophs  photosynthesize.
 You could say that photosynthesis gave birth to codiyions for cons ciousness on Planet