Photosynthesis presentation

2,725 views

Published on

Published in: Technology, Business
1 Comment
3 Likes
Statistics
Notes
No Downloads
Views
Total views
2,725
On SlideShare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
190
Comments
1
Likes
3
Embeds 0
No embeds

No notes for slide

Photosynthesis presentation

  1. 1. PROSES FOTOSINTESIS PADA TUMBUHAN Wenny Pintalitna (813 617 4032) WENNY PINTALITNA (813 617 4032) Rendy M Lanza (813 617 4025) RENDY M LANZA ( 813 617 4025) PASCA SARJANA PENDIDIKAN BIOLOGI FACULTY OF MATHEMATICS AND FACULTY OF MATHEMATICS AND NATURAL SCIENC NATURAL SCIENCE STATE UNIVERSITY OF MEDAN STATE UNIVERSITY OF MEDAN 2013 2013
  2. 2. Food Chain
  3. 3. WHY ARE PLANTS GREEN? Different wavelengths of visible light are seen by the human eye as different colors. Gamma rays X-rays UV Infrared Visible light Wavelength (nm) Microwaves Radio waves
  4. 4. The feathers of male cardinals are loaded with carotenoid pigments. These pigments absorb some wavelengths of light and reflect others. gh ed l i t eflec R t Sunlight minus absorbed wavelengths or colors equals the apparent color of an object.
  5. 5. Why are plants green? d cte e efl R h lig t Transmitted light
  6. 6. AN OVERVIEW OF PHOTOSYNTHESIS • Photosynthesis is the process by which autotrophic organisms use light energy to make sugar and oxygen gas from carbon dioxide and water Carbon dioxide Water Glucose PHOTOSYNTHESIS Oxygen gas
  7. 7. AN OVERVIEW OF PHOTOSYNTHESIS • The light reactions convert solar energy to chemical energy Light Chloroplast NADP+ ADP +P – Produce ATP & NADPH • The Calvin cycle makes sugar from carbon dioxide – ATP generated by the light reactions provides the energy for sugar synthesis – The NADPH produced by the light reactions provides the electrons for the reduction of carbon dioxide to glucose Light reactions Calvin cycle
  8. 8. • The location and structure of chloroplasts Chloroplast LEAF CROSS SECTION MESOPHYLL CELL LEAF Mesophyll CHLOROPLAST Intermembrane space Outer membrane Granum Grana Stroma Inner membrane Stroma Thylakoid Thylakoid compartment
  9. 9. Chloroplast Pigments • Chloroplasts contain several pigments – Chlorophyll a – Chlorophyll b – Carotenoids Figure 7.7
  10. 10. Chlorophyll a & b •Chl a has a methyl group •Chl b has a carbonyl group Porphyrin ring delocalized e- Phytol tail
  11. 11. Different pigments absorb light differently
  12. 12. Klorofil a • Klorofil a adalah pigmen yang secara langsung berpartisipasi dalam reaksi terang
  13. 13. • Two types of photosystems cooperate in the light reactions Photon Photon ATP mill Water-splitting photosystem NADPH-producing photosystem
  14. 14. Plants produce O2 gas by splitting H2O • The O2 liberated by photosynthesis is made from the oxygen in water (H+ and e-)
  15. 15. Noncyclic Photophosphorylation • Photosystem II regains electrons by splitting water, leaving O2 gas as a by-product E Primary electron acceptor Primary electron acceptor El ec tro n tra ns p or t ch ai l ec tro n tra ns po rt n Photons Energy for synthesis of PHOTOSYSTEM I PHOTOSYSTEM II by chemiosmosis
  16. 16. Cyclic Photophosphorylation • Process for ATP generation • Reaction Center => 700 nm
  17. 17. How the Light Reactions Generate ATP and NADPH Primary electron acceptor Energy to make Primary electron acceptor NADP+ 3 2 Light Ele c Light t ro nt r an sp o rt ch ai n Primary electron acceptor 1 Reactioncenter chlorophyll Water-splitting photosystem 2 H+ + 1/2 NADPH-producing photosystem
  18. 18. In the light reactions, electron transport chains generate ATP, NADPH, & O2 • Two connected photosystems collect photons of light and transfer the energy to chlorophyll electrons • The excited electrons are passed from the primary electron acceptor to electron transport chains – Their energy ends up in ATP and NADPH
  19. 19. Chemiosmosis powers ATP synthesis in the light reactions • The electron transport chains are arranged with the photosystems in the thylakoid membranes and pump H+ through that membrane – The flow of H+ back through the membrane is harnessed by ATP synthase to make ATP – In the stroma, the H+ ions combine with NADP+ to form NADPH
  20. 20. The production of ATP by chemiosmosis in photosynthesis H2O CO2 LIGHT NADP+ ADP LIGHT REACTOR CALVIN CYCLE ATP NADPH STROMA (Low H+ concentration) O2 [CH2O] (sugar) Cytochrome complex Photosystem II Photosystem I NADP+ reductase Light 2 H+ 3 Fd NADPH Pq + H+ Pc 2 H2O THYLAKOID SPACE (High H+ concentration) NADP+ + 2H+ 1 1 ⁄2 O2 +2 H+ 2 H+ To Calvin cycle STROMA (Low H+ concentration) Thylakoid membrane ATP synthase ADP ATP P H +
  21. 21. • A Photosynthesis Road Map Chloroplast Light Stroma NADP+ Stack of thylakoids ADP +P Light reactions Calvin cycle Sugar used for • • • • Cellular respiration Cellulose Starch Other organic compounds
  22. 22. Calvin Cycle Light H2O CO2 Input (Entering one 3 CO2 at a time) NADP+ ADP LIGHT REACTION CALVIN CYCLE ATP NADPH O2 Rubisco [CH2O] (sugar) Phase 1: Carbon fixation 3 P 3 P P Short-lived intermediate P Ribulose bisphosphate (RuBP) P 6 3-Phosphoglycerate 6 ATP 6 ADP CALVIN CYCLE 3 ADP 3 ATP 6 P P 1,3-Bisphoglycerate 6 NADPH Phase 3: Regeneration of the CO2 acceptor 5 (RuBP) 6 NADPH+ 6 P P (G3P) 6 P Glyceraldehyde-3-phosphate (G3P) 1 P G3P (a sugar) Output Glucose and other organic compounds Phase 2: Reduction
  23. 23. Siklus Calvin • Dimulai dari CO2 dan menghasilkan Glyceraldehyde 3phosphate • Tiga bagian siklus Calvin menghasilkan 1 produk molekul • Tiga tahap – Fiksasi karbon – Reduksi CO2 – Regenerasi RuBP
  24. 24. 1 Sebuah molekul CO2 dikonversi dari bentuk inorganiknya menjadi molekul organik (fixation) melalui pengikatan ke gula 5C (ribulose bisphosphate atau RuBP). – Dikatalisasi oleh enzim RuBP carboxylase (Rubisco). • Bentuk gula 6C pecah menjadi 3phosphoglycerate
  25. 25. 2 Tiap molekul 3phosphoglycerate menerima tambahan grup fosfat membentuk 1,3-Bisphosphoglycerate (fosforilasi ATP) • NADPH dioksidasi dan elektron yang ditransfer ke 1,3Bisphosphoglycerate memecah molekul dengan tereduksi menjadi Glyceraldehyde 3-phosphate
  26. 26. 3 Tahap terakhir dari siklus ini adalah regenerasi RuBP • Glyceraldehyde 3phosphate dikonversi menjadi RuBP melalui sebuah seri reaksi yang melibatkan fosforilasi molekul oleh ATP
  27. 27. Tanaman C3 dan C4 a) Tanaman C3 – CO2 dapat langsung masuk ke dalam siklus Calvin sehingga membentuk gliseraldehid 3 fosfat yang memiliki 3 molekul karbon – Tanaman C3 umumnya terdapat di tempattempat dengan konsentrasi CO2 yang tinggi
  28. 28. Jalur Tumbuhan C3
  29. 29. b) Tanaman C4  Musim panas penguapan besar - CO2 dalam jumlah sedikit fotosintesis dapat terhenti.  Enzim modifikasi CO2 menjadi okasaloasetat tersebih dulu sebelum masuk ke dalam siklus Calvin.  Contoh: alang-alang, jagung dan tebu
  30. 30. Jalur Tumbuhan C4
  31. 31. • Anatomi daun C4 dan jalur C4 Photosynthetic cells of C4 plant leaf Mesophyll cell Mesophyll cell Bundlesheath cell CO CO2 2 PEP carboxylase PEP (3 C) Oxaloacetate (4 C) ADP Vein (vascular tissue) Malate (4 C) ATP C4 leaf anatomy BundleSheath cell Pyruate (3 C) CO2 Stoma CALVIN CYCLE Sugar Vascular tissue
  32. 32. Comparison between C3 and C4 Leaf C3 dan C4
  33. 33. • Tanaman CAM – Malam hari, respirasi tidak sempurna. – KH diubah menjadi asam malat, CO2 tidak dilepaskan, pH tetap tinggi (7), pati dalam sel penjaga dihidrolisis menjadi gula, Ψs nya menurun, terjadi endoosmosis, Ψp sel penjaga naik, turgor, dinding sel penjaga tertekan ke arah luar, stomata membuka. • Selama siang hari, stomata tertutup – CO2 dilepaskan dari asam organik untuk digunakan dalam siklus Calvin
  34. 34. • Jalur CAM mirip dengan jalur C4 Pineapple Sugarcane C4 Mesophyll Cell Organic acid Bundlesheath cell (a) Spatial separation of steps. In C4 plants, carbon fixation and the Calvin cycle occur in different types of cells. CALVIN CYCLE Sugar CAM CO2 1 CO2 incorporated into four-carbon organic acids (carbon fixation) 2 Organic acids release CO2 to Calvin cycle CO2 Organic acid Night Day CALVIN CYCLE Sugar (b) Temporal separation of steps. In CAM plants, carbon fixation and the Calvin cycle occur in the same cells at different times.
  35. 35. Factors Affecting Photosynthesis Rate • Intensitas Cahaya Laju fotosintesis maksimum ketika banyak cahaya. • Konsentrasi Karbon Dioksida Semakin banyak karbon dioksida di udara, makin banyak jumlah bahan yang dapat digunakan tumbuhan untuk melangsungkan fotosintesis. • Suhu Enzim-enzim yang bekerja dalam proses fotosintesis hanya dapat bekerja pada suhu optimalnya. • Kadar air Kekeringan menyebabkan stomata menutup - menghambat penyerapan karbon dioksida - mengurangi laju fotosintesis.
  36. 36. •Kadar fotosintat (hasil fotosintesis) Jika kadar fotosintat seperti karbohidrat berkurang, laju fotosintesis akan naik. •Tahap pertumbuhan Penelitian menunjukkan bahwa laju fotosintesis jauh lebih tinggi pada tumbuhan yang sedang berkecambah ketimbang tumbuhan dewasa dikarenakan tumbuhan berkecambah memerlukan lebih banyak energi dan makanan untuk tumbuh.

×