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

 Photosynthesis : part  - The Light Reactions
  Lecture by Glenn Wolkenfeld
 
 A music  by Glenn Wolkenfeld
 Boys and girls tell me  you think of this,
 Time for  lesson ‘bout photosynthesis
 Cells use light to combine  carbon dioxide.
 Gonna see electrons going for a  ride.
 Making  making sweet O¬2.
  why should photosynthesis matter to you?
 Food on your 
  rich atmosphere.
 Without photosynthesis  simple wouldn’d be here.
 
  Part I, The Big Picture)
 Photosynthesis is a  reaction.
  by light using enzymatic action.
 Water’s oxidized, CO2’s  duced
 The sugar that  you drink in orange juice.
 The overall reaction has two 
  is the light reactions which has as its basis.
 Light powered  of ATP.
 O2 is the by – product and you will 
 Production of electron carrier 
 Which provides reducing power needed in the  phase
 ‘Cause  during phase 2
 Provides what’s needed for reducing 
 NADPH ia made by a reduction of NADP+,  function
  to absorb electrons and pick up H,
 Gaining energy and making 
 Phase 2 is the Calvin Cycle  carbohydrate,
 Like sugar and starches and fibers on your lunch 
 It’s how  make food animals eat.
 Photosynthesis, it’s  sweet!
 
  II: Chloroplasts, Thylakoids, Light, and Chlorophyll)
 In a lesf  mesophyllic tissue
 And cells with chloroplasts  to the issue.
 Chloroplasts are almost like  in every way,
  their own ribosomes and their own DNA.
 They even reproduce themselves,  into half.
  clue for this organelle’s independent past.
 This theory has a  endosymbiosis,
 Developed in  60s by Lynn Margulis.
 Inside the chloroplast  the fluid stroma.
 It’s true  Tokyo.
 It’s true in 
 Stroma syrrounds  thylakoids.
 Each one has a hollow  inside.
 The thylakoid’s membrane is loaded with 
  it’s the light reactions’ scene.
 It’s all  using light for powering electrons,
 All about  the power in photons.
 The photons needed are are those  light,
 Which  the energy to make the world bright.
 The highest frequency that we  see,
 Is violet light  wavelength 380.
 380 nanometers, sounds 
 But next to gamma rays  rather tall.
 Red light  at 750.
  the visible spectrum nifty?
 Photons are packets of light 
 Both  wave and a particle, you see.
 Phootins get adsorbed  pigments.
 It’s real, it’s true, it ain’t  figment!
 Most important are green 
 Orange carotenoids, and yellow 
 Together they absorb light, mostly red  blue.
 The green is  absorbed it reflects back to you.
 In chlorophyll  the porphyrin ring.
 See  magnesium, which makes you want to sing,
  metal with valence two.
 You’ll  those electrons rocketing through.
 Notice the tail, a hydrocarbon 
 Which anchors chlorophyll  the thylakoid membrane.
 A molecule with  so pretty,
 In the thylakoid  makes electricity!
 
  Part III)
  showed us the action spectrum.
 Used a prism  break the sun’s
  into its frequencies.
  it on spirogyra, filamentous algae.
 The O2 algae make  stimulate bacteria.
 Which will grow in any oxygen  rich area.
 Bacteria loved it  blue and red,
 But hardly grew over green, they might  well be dead!
 The line of growth is a refection,  photosynthesis’ action spectrum.
 Note  won’t match, exactly,
 The absorption spectra of chlorophyll a or 
 ‘Cause the cartenoids  xanthophylls we’ve met,
  light frequencies the chlorophylls can’t get.
 And in  thylakoid they all cooperate,
 In using light to  carbohydrate.
 Consider  in isolation,
 Shine  light upon it (call it photoexcitation)
 The  electrons in magnessium
 Jump to an  state, it’s so fun!
 But once up at  level, they can only fall.
  to where they started, like a bouncing ball.
 These falling alectrons,  energy,
 Fluorescing  red light, as you can see.
 But  thylakoids, chlorophyll’s not alone,
  a photosystem is chlorophyll’s home.
 The photosystem’s parts can  photons,
 And  their energy to move electrons.
 The system’s antenna complex does  first capture,
  photon anergy into electron rapture.
 The energized electrons bounce like  ball,
 At the  center, they jump but do not fall.
 A primary electron  grabs them from on top,
  yanks them with a force reaction center cannot stop.
 To this  reaction center we’ll return,
  the details of electron flow it now is time to learn.
 
  Part IV) ATP Synthesis in Non – Cyclic Electron Flow.
  -  cycle flow is the main pathway.
 Much confustion  to the way
 Hootoystm II precedes photosystem 
  a fct to memorize, just get it done!
 PS II’s antenna captures  photon,
 Generates  flow of electrons.
 All  the world, even n Haiti,
  flow to reaction center P680.
  electrons do not hover,
  acceptor passes them over.
 To the electron  chain,
 In the thylakoid 
 This chain’s like a bucket 
 Each molecule has a similar 
 They take  electrons,
 And use  energy for pumping protons.
 From stroma to the  space.
  protons into that place.
  makes a gradient across the thylkoid membrane
  protons want “out” or they’ll go insane.
  the protons can’t permeate.
 The membrane won’t allow 
  only one port through which they travel.
 It’s the ATP Synthase 
 The “-ase” tells you  is an enzyme.
 Which makes ATP  the time.
 It has binding  for ADP and Pi,
 And channels for diffusing  whose knetic energy.
 Changes the  sites’ conformation.
 Fusing ADP with Pi which  your information.
 Is how thylakoids make 
 Life’s key  of energy.
 From respiration this  feel familiar.
 ATP is made this way  mitochondria.
 Chemiosomosis  the name
 ATP production is the 
 
 (  V: NADPH Synthesis in Non – Cyclic Elecron Flow)
 Back to our electons moved by the 
 Flowing  Photosystem II to System I.
 They get to PS I lke  used up battery.
 The  chain used up their energy.
  when light hits PS I’s antenna
 Electrons boune to reaction 
 This one’s 
 That  makes electrons go!
 PS T’s  acceptor grabs them away,
  P700 in an oxidized way.
 And P700 with its oxidized blues accepts the alectrons  PS II.
 Bak to electron from PS 
 It now gose for a ride, having  own fun.
 But  proton pumps ain’t its fate.
  travels to NADP+ reductase.
 An enzyme plant  count upon.
 To pass  H and electrons.
 To NADP+  gets reduced.
 It’s  NADPH get produced.
 
 (Part VI:  Production in Non – Cycli Electron Flow)
 The by – product of these light 
 Is oxygen  how it happens.
 Back PS II, it came to 
 That P680  oxidized
 To replace lost  P680 liberates.
  from water which dissociates.
 Into one oxygen and protons 
 The single O  meet anoher forming O2.
  protons are formed in the thylakoid space.
 Increasing  concentration in that place.
 So we see  side effect of water’s oxidation.
 Is enhancement of ATP