Photosynthesis presentation

36
WENNY PINTALITNA (813 617 4032) RENDY M LANZA ( 813 617 4025) FACULTY OF MATHEMATICS AND NATURAL SCIENCE STATE UNIVERSITY OF MEDAN 2013 PROSES FOTOSINTESIS PROSES FOTOSINTESIS PADA TUMBUHAN PADA TUMBUHAN Wenny Pintalitna (813 617 4032) Rendy M Lanza (813 617 4025) PASCA SARJANA PENDIDIKAN BIOLOGI FACULTY OF MATHEMATICS AND FACULTY OF MATHEMATICS AND NATURAL SCIENCE NATURAL SCIENCE STATE UNIVERSITY OF MEDAN STATE UNIVERSITY OF MEDAN 2013 2013

Transcript of Photosynthesis presentation

Page 1: Photosynthesis presentation

WENNY PINTALITNA (813 617 4032) RENDY M LANZA ( 813 617 4025)

FACULTY OF MATHEMATICS AND NATURAL SCIENCESTATE UNIVERSITY OF MEDAN

2013

PROSES FOTOSINTESISPROSES FOTOSINTESIS PADA TUMBUHAN PADA TUMBUHAN

Wenny Pintalitna (813 617 4032)

Rendy M Lanza (813 617 4025)

PASCA SARJANA PENDIDIKAN BIOLOGI FACULTY OF MATHEMATICS AND FACULTY OF MATHEMATICS AND NATURAL SCIENCENATURAL SCIENCE

STATE UNIVERSITY OF MEDANSTATE UNIVERSITY OF MEDAN20132013

Page 2: Photosynthesis presentation

Food Chain

Page 3: Photosynthesis presentation

Different wavelengths of visible light are seen by the human eye as different colors.

WHYWHY ARE ARE PLA PLANTS NTS GREGREEN?EN?

Gammarays

X-rays UV Infrared Micro-waves

Radiowaves

Visible light

Wavelength (nm)

Page 4: Photosynthesis presentation

Sunlight minus absorbed Sunlight minus absorbed wavelengths or colors wavelengths or colors equals the apparent color equals the apparent color of an object.of an object.

The feathers of male cardinals are loaded with carotenoid pigments. These pigments absorb some wavelengths of light and reflect others.

Reflected light

Page 5: Photosynthesis presentation

Why are plants green?

Reflected lig

ht

Transmitted light

Page 6: Photosynthesis presentation

• Photosynthesis is the process by which autotrophic organisms use light energy to make sugar and oxygen gas from carbon dioxide and water

AN OVERVIEW OF PHOTOSYNTHESIS

Carbondioxide

Water Glucose Oxygengas

PHOTOSYNTHESIS

Page 7: Photosynthesis presentation

• 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

LightChloroplast

Lightreactions

Calvincycle

NADP

ADP+ P

• The light reactions convert solar energy to chemical energy– Produce ATP & NADPH

AN OVERVIEW OF PHOTOSYNTHESIS

Page 8: Photosynthesis presentation

• The location and structure of chloroplasts

LEAF CROSS SECTION MESOPHYLL CELL

LEAF

Chloroplast

Mesophyll

CHLOROPLAST Intermembrane space

Outermembrane

Innermembrane

ThylakoidcompartmentThylakoidStroma

Granum

StromaGrana

Page 9: Photosynthesis presentation

• Chloroplasts contain several pigments

Chloroplast Pigments

– Chlorophyll a – Chlorophyll b – Carotenoids

Figure 7.7

Page 10: Photosynthesis presentation

Chlorophyll a & b•Chl a has a methyl group •Chl b has a carbonyl group

Porphyrin ring delocalized e-

Phytol tail

Page 11: Photosynthesis presentation

Different pigments absorb light differently

Page 12: Photosynthesis presentation

Klorofil a

• Klorofil a adalah pigmen yang secara langsung berpartisipasi dalam reaksi terang

Page 13: Photosynthesis presentation

Ph

oto

n

Ph

oto

n

Water-splittingphotosystem

NADPH-producingphotosystem

ATPmill

• Two types of photosystems cooperate in the light reactions

Page 14: Photosynthesis presentation

• The O2 liberated by photosynthesis is made from the oxygen in water (H+ and e-)

Plants produce OPlants produce O22 gas by splitting H gas by splitting H22OO

Page 15: Photosynthesis presentation

Primaryelectron acceptor

Primaryelectron acceptor

Electron transport chain

Electron transport

Photons

PHOTOSYSTEM I

PHOTOSYSTEM II

Energy forsynthesis of

by chemiosmosis

Noncyclic Photophosphorylation • Photosystem II regains electrons by splitting

water, leaving O2 gas as a by-product

Page 16: Photosynthesis presentation

Cyclic Photophosphorylation • Process for ATP generation • Reaction Center => 700 nm

Page 17: Photosynthesis presentation

2 H + 1/2

Water-splittingphotosystem

Reaction-center

chlorophyll

Light

Primaryelectronacceptor

Energyto make

Electron transport chain

Primaryelectronacceptor

Primaryelectronacceptor

NADPH-producingphotosystem

Light

NADP

1

23

How the Light Reactions Generate ATP and NADPH

Page 18: Photosynthesis presentation

• 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

In the light reactions, electron transport In the light reactions, electron transport chains generate ATP, NADPH, & Ochains generate ATP, NADPH, & O22

Page 19: Photosynthesis presentation

• 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

Chemiosmosis powers ATP synthesis in the light reactions

Page 20: Photosynthesis presentation

The production of ATP by chemiosmosis in photosynthesis

LIGHTREACTOR

NADP+

ADP

ATP

NADPH

CALVINCYCLE

[CH2O] (sugar)STROMA(Low H+ concentration)

Photosystem II

LIGHT

H2O CO2

Cytochromecomplex

O2

H2OO2

1

1⁄2

2

Photosystem ILight

THYLAKOID SPACE(High H+ concentration)

STROMA(Low H+ concentration)

Thylakoidmembrane

ATPsynthase

PqPc

Fd

NADP+

reductase

NADPH + H+

NADP+ + 2H+

ToCalvincycle

ADP

PATP

3

H+

2 H++2 H+

2 H+

Page 21: Photosynthesis presentation

• A Photosynthesis Road Map

Chloroplast

Light

Stack ofthylakoids ADP

+ P

NADP

Stroma

Lightreactions

Calvincycle

Sugar used for

Cellular respiration Cellulose

Starch

Other organic compounds

Page 22: Photosynthesis presentation

Calvin Cycle

(G3P)

Input(Entering one

at a time)CO2

3

Rubisco

Short-livedintermediate

3 P P

3 P P

Ribulose bisphosphate(RuBP)

P

3-Phosphoglycerate

P6 P

6

1,3-Bisphoglycerate

6 NADPH

6 NADPH+

6 P

P6

Glyceraldehyde-3-phosphate(G3P)

6 ATP

3 ATP

3 ADP CALVINCYCLE

P5

P1

G3P(a sugar)Output

LightH2O CO2

LIGHTREACTION

ATP

NADPH

NADP+

ADP

[CH2O] (sugar)

CALVINCYCLE

O2

6 ADP

Glucose andother organiccompounds

Phase 1: Carbon fixation

Phase 2:Reduction

Phase 3:Regeneration ofthe CO2 acceptor(RuBP)

Page 23: Photosynthesis presentation

Siklus Calvin

• Dimulai dari CO2 dan menghasilkan Glyceraldehyde 3-phosphate

• Tiga bagian siklus Calvin menghasilkan 1 produk molekul

• Tiga tahap– Fiksasi karbon– Reduksi CO2– Regenerasi RuBP

Page 24: Photosynthesis presentation

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 3-phosphoglycerate

Page 25: Photosynthesis presentation

2 Tiap molekul 3-phosphoglycerate menerima tambahan grup fosfat membentuk 1,3-Bisphosphoglycerate (fosforilasi ATP)

• NADPH dioksidasi dan elektron yang ditransfer ke 1,3-Bisphosphoglycerate memecah molekul dengan tereduksi menjadi Glyceraldehyde 3-phosphate

Page 26: Photosynthesis presentation

3 Tahap terakhir dari siklus ini adalah regenerasi RuBP

• Glyceraldehyde 3-phosphate dikonversi menjadi RuBP melalui sebuah seri reaksi yang melibatkan fosforilasi molekul oleh ATP

Page 27: Photosynthesis presentation

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 tempat-tempat dengan konsentrasi CO2 yang tinggi

Page 28: Photosynthesis presentation

Jalur Tumbuhan C3

Page 29: Photosynthesis presentation

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

Page 30: Photosynthesis presentation

Jalur Tumbuhan C4

Page 31: Photosynthesis presentation

• Anatomi daun C4 dan jalur C4

CO2

Mesophyll cell

Bundle-sheathcell

Vein(vascular tissue)

Photosyntheticcells of C4 plantleaf

Stoma

Mesophyllcell

C4 leaf anatomy

PEP carboxylase

Oxaloacetate (4 C) PEP (3 C)

Malate (4 C)

ADP

ATP

Bundle-Sheathcell CO2

Pyruate (3 C)

CALVINCYCLE

Sugar

Vasculartissue

CO2

Page 32: Photosynthesis presentation

Comparison between C3 and C4 LeafC3 dan C4

Page 33: Photosynthesis presentation

• 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

Page 34: Photosynthesis presentation

• Jalur CAM mirip dengan jalur C4

Spatial separation of steps. In C4 plants, carbon fixation and the Calvin cycle occur in differenttypes of cells.

(a) Temporal separation of steps. In CAM plants, carbon fixation and the Calvin cycle occur in the same cellsat different times.

(b)

PineappleSugarcane

Bundle-sheath cell

Mesophyll Cell

Organic acid

CALVINCYCLE

Sugar

CO2 CO2

Organic acid

CALVINCYCLE

Sugar

C4 CAM

CO2 incorporatedinto four-carbonorganic acids(carbon fixation)

Night

Day

1

2 Organic acidsrelease CO2 toCalvin cycle

Page 35: Photosynthesis presentation

Factors Affecting Photosynthesis Rate

• Intensitas CahayaLaju fotosintesis maksimum ketika banyak cahaya.

• Konsentrasi Karbon DioksidaSemakin banyak karbon dioksida di udara, makin banyak jumlah bahan yang dapat digunakan tumbuhan untuk melangsungkan fotosintesis.

• SuhuEnzim-enzim yang bekerja dalam proses fotosintesis hanya dapat bekerja pada suhu optimalnya.

• Kadar airKekeringan menyebabkan stomata menutup - menghambat penyerapan karbon dioksida - mengurangi laju fotosintesis.

Page 36: Photosynthesis presentation

•Kadar fotosintat (hasil fotosintesis)Jika kadar fotosintat seperti karbohidrat berkurang, laju fotosintesis akan naik.

•Tahap pertumbuhanPenelitian 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.