🎵 Luyện Nghe Bài Hát: Photosynthesis - The Light Reactions - Glenn Wolkenfeld

 Photosynthesis  part A - The Light Reactions
 Amusical Lecture by Glenn 
 
 A music Lecture by  Wolkenfeld
 Boys and girls tell me what you think  this,
 Time for a  ‘bout photosynthesis
 Cells use light to  water carbon dioxide.
 Gonna  electrons going for a wild ride.
 Making sugar,  sweet O¬2.
 But why should photosynthesis matter to 
 Food on  table.
  rich atmosphere.
 Without photosynthesis  simple wouldn’d be here.
 
 ( Part I,  Big Picture)
 Photosynthesis is a redox 
 Powered by  using enzymatic action.
 Water’s  CO2’s re duced
 The sugar that results you  in orange juice.
 The overall reaction  two phases.
 First is the light reactions which has as  basis.
  powered production of ATP.
 O2 is the by – product and  will see.
 Production of electron  NADPH
  provides reducing power needed in the second phase
 ‘Cause NADPH, during  2
 Provides what’s needed for  CO2
 NADPH ia made by  reduction of NADP+, whose function
  to absorb electrons and pick up H,
  energy and making NADPH.
 Phase 2 is  Calvin Cycle makes carbohydrate,
 Like sugar and starches and fibers on your  plate.
 It’s how plants make food animals 
 Photosynthesis,  so sweet!
 
 (Part II: Chloroplasts, Thylakoids, Light,  Chlorophyll)
 In a  there’s mesophyllic tissue
 And cells with chloroplasts key to  issue.
 Chloroplasts are almost  cells in every way,
 With their own ribosomes  their own DNA.
 They even reproduce themselves, splitting  half.
 A clue for this  independent past.
 This theory has  name endosymbiosis,
 Developed in the 60s by  Margulis.
 Inside the chloroplast is  fluid stroma.
  true in Tokyo.
 It’s true  Roma.
 Stroma syrrounds little 
 Each one has a  space inside.
  thylakoid’s membrane is loaded with protein.
  it’s the light reactions’ scene.
 It’s all about using light for  electrons,
 All about grabbing the power  photons.
 The photons needed are are those  light,
 Which has the energy to make the world 
 The highest frequency that  can see,
 Is  light with wavelength 380.
  nanometers, sounds small,
 But next to gamma rays it’s  tall.
 Red light shines  750.
  the visible spectrum nifty?
  are packets of light energy,
 Both a wave and a  you see.
 Phootins get adsorbed by 
 It’s real, it’s true, it ain’t no 
 Most important are green 
 Orange carotenoids, and yellow 
 Together they absorb  mostly red and blue.
 The green is  absorbed it reflects back to you.
 In chlorophyll see the porphyrin 
  the magnesium, which makes you want to sing,
  metal with valence two.
 You’ll see those electrons  through.
 Notice  tail, a hydrocarbon chain.
 Which anchors chlorophyll into the thylakoid 
 A molecule with  so pretty,
 In the  it makes electricity!
 
 (  III)
 Englemann showed us the action 
 Used a  to break the sun’s
 Light  its frequencies.
 Shone  on spirogyra, filamentous algae.
 The O2  make will stimulate bacteria.
  will grow in any oxygen – rich area.
 Bacteria loved  over blue and red,
 But  grew over green, they might as well be dead!
 The line of growth is a refection, of photosynthesis’ action 
 Note this won’t  exactly,
 The absorption spectra of chlorophyll a  b.
 ‘Cause the cartenoids  xanthophylls we’ve met,
 Absorb  frequencies the chlorophylls can’t get.
 And  the thylakoid they all cooperate,
  using light to synthesize carbohydrate.
 Consider chlorophyll in 
 Shine some  upon it (call it photoexcitation)
  valence electrons in magnessium
 Jump  an excited state, it’s so fun!
 But once up at  level, they can only fall.
 Back to  they started, like a bouncing ball.
  falling alectrons, release energy,
 Fluorescing as red light, as you can 
 But in  chlorophyll’s not alone,
 Instesd  photosystem is chlorophyll’s home.
 The photosystem’s parts can take 
 And use their  to move electrons.
 The  antenna complex does the first capture,
 Changing  anergy into electron rapture.
 The energized  bounce like a ball,
 At the reaction center, they jump but do  fall.
 A primary electron acceotor grabs them  on top,
 And yanks them with a  reaction center cannot stop.
 To this  reaction center we’ll return,
 But the details of electron flow it now is time  learn.
 
 ( Part IV) ATP Synthesis in Non –  Electron Flow.
 Non   cycle flow is the main pathway.
 Much confustion  to the way
 Hootoystm II precedes  I.
  a fct to memorize, just get it done!
 PS  antenna captures a photon,
 Generates a  of electrons.
 All  the world, even n Haiti,
 They flow to reaction center 
 There electrons  not hover,
  acceptor passes them over.
 To the  transport chain,
  the thylakoid membrane.
 This chain’s  a bucket brigade.
 Each  has a similar trade.
 They take  electrons,
 And  their energy for pumping protons.
 From  to the thylakoid space.
 Packing protons into  place.
 This makes  gradient across the thylkoid membrane
 The protons want “out” or they’ll go 
 But the protons can’t 
 The membrane  allow escape.
 There’s only one port through  they travel.
  the ATP Synthase channel.
 The  tells you this is an enzyme.
 Which makes  all the time.
 It has binding sites for ADP and 
 And channels for  protons whose knetic energy.
 Changes the binding sites’ 
 Fusing ADP with Pi which for your 
 Is how thylakoids make 
 Life’s key  of energy.
 From respiration this might  familiar.
 ATP is made this way  mitochondria.
  is the name
 ATP production  the game.
 
 ( Part V: NADPH Synthesis in Non –  Elecron Flow)
 Back to our  moved by the sun.
 Flowing from  II to System I.
 They get to PS I lke a used  battery.
 The transport chain used up their 
 But when light hits  I’s antenna
 Electrons boune to reaction 
 This one’s 
 That  makes electrons go!
 PS T’s electron acceptor grabs them 
 Leaving P700 in an oxidized 
 And P700 with its oxidized blues accepts the  from PS II.
 Bak to electron  PS I.
 It now gose for a ride,  its own fun.
 But powering  pumps ain’t its fate.
 It travels to  reductase.
  enzyme plant cells count upon.
 To pass  H and electrons.
 To NADP+  gets reduced.
 It’s how  get produced.
 
 (Part VI: Oxygen Production in  – Cycli Electron Flow)
 The  – product of these light reactions
 Is oxygen  how it happens.
 Back PS II, it came  arise,
 That  got oxidized
 To replace lost electrons P680 
 Electrons from water which 
 Into  oxygen and protons two,
 The single O will meet anoher forming 
 These protons are  in the thylakoid space.
  proton concentration in that place.
 So we see a side effect of water’s 
 Is enhancement  ATP creation.