plant physiology lectures

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Introductionدمة� مق�Cells, the basic unites of life, require membranes for their existence.اة� ة� للحي ساسي ة� الأ� ي ف� ي �ة� والوظ ي ب" ة� الوحدة� الت�ركي لي ر الخ� ت, عت� ت�

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prokaryotic Cells1. Without a nucleus2. Genetic materials are not enclosed within a membrane3. The Genetic materials is a single circular DNA and is contained in the cytoplasmDo not have internal organellesEukaryotic Cells1.With a nucleus 2. The Genetic materials is surrounded by a membrane much like the cell’s membrane 1.The Genetic material forms multiple chromosomes • Animal cells1. Lysosomes• Plant Cells1. Cell wall2. Plastids3. Large central vacuole

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• Animal cells1. Lysosomes• Plant Cells1. Cell wall2. Plastids3. Large central vacuole

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The plant cell

II- The protoplast I- The cell wall

II- the nucleus

Nuclear envelope

nucleoplasm

I- the cytoplasm

A- surrounded byThe plasma membrane

B- Cytoplasm organelles

Mitochondrion

Plastids

Ribosomes

Micro bodies

C- Membranous structures

Endoplasmic reticulum

Golgi apparatus

D- Vacuole

nucleolus

Pores

Middle lamella plasmodesmata Secondary

cell wallPrimary cell wall

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1 -Cell Wall A- structure found around plant cells, fungi cells, and certain protists, as well as prokaryotic cells .

B- Located outside of the plasma membrane and is composed primarily of cellulose (in plants).D- contains:

1-Plasmodesmata:connect neighboring cells

2 -Primary cell walls:all plant cells

3 -Secondary cell walls:1-only in some cells

2 -Lignin--polymer of alcohols, stable, resistant waterproof coating

4 -middle lamella

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I-Cytoplasm semi fluid, that serves as a

pool of raw materials .Consists ofwater(70%)proteins (mostly)

carbohydrates ,and nucleotides, as well as their monomers.

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1 -Plasma Membrane A- selectively permeable membrane that is approximately 0.1 um thickPlasma membrane functions

1 -The plasma membrane (PM) functions as an active interface between the cell and its environment .

2 -With ER, the PM produces plasmodesmata :

3 -membrane tubes that cross cell walls and provide communication between adjacent cells.

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The Plasma Membrane

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Membrane models : ة�88 ل888و88ي ة�88 الخ� ي غ�ش8> ج? الأ� م8888ا88ذ�8 ن88888888�The fluid mosaic model :ل ر888ق�ش> الس88ائ8� ل المت8888,Lئ المو888ذ8

ن? ي ي� ف� ا على ظي, س> وي الغ� Vحت يDouble layer

PhospholipidsWith their

Carbohydrate tail Peripheralprotein

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Membranes Properties Membranes consist of a bilayer of polar lipid molecules and associated membranes .

The lipid bilayer serves as a general permeability barrier. Water soluble (polar) molecules cannot penetrate the lipid nonpolar interior.

Proteins perform most of membrane functions and therefore define the specificity of each membrane system.

The amphipathic nature of lipids means: they contain both hydrophilic and hydrophobic domains.

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Transport ى ل السلب, ق� passive transportالي� ط ش> ل الن� ق� Active transportالي�

ة� ذون? ي ش> غ� لأل الأ� ة� مرور المواذ ح� عملية� لى طاق� hة� ا الخاج,

Diffusion

Ion Exchange

Mass flow

ة� ي ش> غ� لأل الأ� ة� مرور المواذ ح� لأت� وحوامل عملي ي, ف� وذمشي� ة� ووح, لى طاق� hاج? ا حت� يReceptors or carriers

Transport across membranes : ة�88 ي غ�ش> ر8 الأ� ل عت88888888, ق�88 الي�

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سم ف� سمت� ف� ت�دات� ي لأسب� دات�الي, ي لأسب� الي,

اh لىاh لى ::

Chloroplasts Chloroplasts را ض� دات� الخ� ي لأسب� رالي, ض� دات� الخ� ي لأسب� ,Site of photosynthesis, Site of photosynthesis ءءلي,contain chlorophyllcontain chlorophyll

pigment, pigment, double membranesdouble membranes ل ا ي ة� الت�مب> ولة� غن? عملي ل امشت� ي ة� الت�مب> ولة� غن? عملي مشت�

�ى وئ �ى لض� وئ ل ، ،لض� ي وي8 على الكلوروق� Vحت لي� ي وي8 على الكلوروق� Vحت ذوج? ، ،ي� اء مر� س> ذوج?وعلى سطحها غ� اء مر� س> وعلى سطحها غ�

b) Chromoplasts b) Chromoplasts ة� دات� الملوي� ي لأسب� ة�الي, دات� الملوي� ي لأسب� الي,

store yellow, store yellow, orange, andorange, and

red pigmentsred pigments give the color give the color

to fruitsto fruits and flowers and flowers ضف�راءات� ال ع� ن? الصي, خ�ر� ات� الضف�راءي� ع� ن? الصي, خ�ر� ي� ولة� ،، ة� ،مشت� الي ق� ت�� ر ولة�الحمراء والت, ة� ،مشت� الي ق� ت�� ر هار والت>مارالحمراء والت, ر� هار والت>مارغن? لون? الأ� ر� غن? لون? الأ�

c) Leucoplastsc) Leucoplasts مة� اللون? ن� دات� عد ي لأسب� مة� اللون?الي, ن� دات� عد ي لأسب� الي,store starches store starches and proteinsand proteins in plantsin plants?نولة� غ ولة� غن?مشت� اء مشت� س> ن? الن� Lي خ�ر� اءي� س> ن? الن� Lي خ�ر� ي� ن? والدهون? ،، ي ن? والدهون?الت,روئ� ي الت,روئ�

D- AmyloplastsD- Amyloplasts ة� وي ش> دات� الن� ي لأسب� ة�الي, وي ش> دات� الن� ي لأسب� الي,

are starch-storing are starch-storing plastids plastids ن? Lي خ�ر� ولة� غن? ي� ن?مشت�Lي خ�ر� ولة� غن? ي� مشت�ا لأي ى ح� اء ف� س> االن� لأي ى ح� اء ف� س> الن�

س طاطي ات� الب, سذري� طاطي ات� الب, ذري�رة� وت, الد� رة�وحت, وت, الد� وحت,

E- Etioplasts E- Etioplasts اءاا ض� ب دات� الب" ي لأسب� اءلي, ض� ب دات� الب" ي لأسب� لي,دات� ي لأسب� دات�ي, ي لأسب� ي,

وي Vحت وي لأي� Vحت لأي� ل ي لعلى الكلوروق� ي على الكلوروق�وي على Vحت وي علىولكن? ي� Vحت ولكن? ي�ل ي لمولد الكلوروق� ي مولد الكلوروق�

(protochlorophyllide(protochlorophyllide((

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ChloroplastsChloroplastsدات� ي لأسب� دات�الي, ي لأسب� راالي, ض� را الخ� ض� الخ�

1- green plastids1- green plastids responsible for responsible for photosynthesis.photosynthesis.ل ي مب> ة� الت� ولة� غن? عملي لمشت� ي مب> ة� الت� ولة� غن? عملي مشت� �ى وئ �ى اض� وئ اض�

It composed of: ت�ركب, من? VLي و

Outer envelope ى ارج, لأف� الخ� الع� Inner envelope

لى لأف� الداح� الع�Stroma lamellaeوة� ة� الحش> ي ش> غ� ا�

Thylakoid Membraneة� ي ش> غ� دا� لأكوي ي الب>

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Carbon linked reaction

Light dependent

reaction

Thylakoid membrane

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Chloroplasts:

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Chloroplasts :

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Amyloplasts

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Etioplasts :

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Plastids contain DNA and RNAPlastids reproduce by division of existing plastids or Proplastids

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Mitochondria(ا دري� وكوي� ت� )المبة� ف� ي �ب, والوظ الت�ركي

Inner Membrane

)ETC andATP(( لى لأف� الداح� ال)الع� ق� ي� ن£ hة� ا اج? عملي ي� ن�£ hات� وا كت�روي� hالأATPة ي م ق� ت� ن�

Outer membrane( ى ارج, لأف� الخ� )الع�

Matrix)Genome :

TCA Enzymes( وي على)المات�ركس) Vحت ي�ة� ي مات� ذورة�المعلومات� الوران�> ن� ر£ ت� h,سواربك

CristaeInter

membraneSpace

)transporters(

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ال ق� ي� ن£ hة� ا ات� عملي لكت�روي� hاج?الأ ي� ن�£ hوا ATP م ت� ن� ة ي ق�

وي على المعلومات� Vحت مات� ذورة� كرب,سالمات�ركس ي� ن� ر£ ت� hة� وا ي الوران�>

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The MicrobodiesThe Microbodies))Peroxisomes and/orPeroxisomes and/or

GlyoxysomesGlyoxysomes((ة� ف� ي مات� الدق� شت ة�الح, ف� ي مات� الدق� شت الح,

composed ofcomposed of a single membranea single membraneف�رذاء م س> ت�ركب, من? غ� Vف�رذياء م س> ت�ركب, من? غ� Vي..

Their role depends onTheir role depends on he organ or tissue in Whichhe organ or tissue in Whichthey occurthey occur لىغت�مد ع غت�مد علىذورها ت ة:ذورها ت ي وذة� ق� ى الموح, لب� ي, ر� الب� ة:الخ, ي وذة� ق� ى الموح, لب� ي, ر� الب� الخ,

In seeds, they areIn seeds, they are involved in lipidinvolved in lipid MobilizationMobilization ل حوئ� Vت وم ن, ق� ور ت� د� ى الي, ل ف� حوئ� Vت وم ن, ق� ور ت� د� ى الي, ف�

ات� لى سكري� hون? ادهات�ال لى سكري� hون? ادهال

in leaves of C3 plantsin leaves of C3 plants , ,they play major rolethey play major role

in photorespirationin photorespiration ( وراق� ى الأ� ) ف� وراق� ى الأ� ت رC3C3ف� لغب, ذور كت" ر) ي� ت لغب, ذور كت" ) ي� �ى وئ س الض� ف� ي� Vبال ى �ى ف� وئ س الض� ف� ي� Vبال ى ف�

in legume root nodulesin legume root nodulesthey are involved in Nthey are involved in N metabolism. metabolism. وم ق� ات� ت� ولي ق� ة� للي, ري د� د الخ, ى العق� ومف� ق� ات� ت� ولي ق� ة� للي, ري د� د الخ, ى العق� ف� ن? ي ت�روح, ت ل الي� ي مب> ى ن� ن?ف� ي ت�روح, ت ل الي� ي مب> ى ن� ف�

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Glyoxysomes

Oil body

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ف� ائ� � ERوط

give rise to endo membrane system

ER export site Produces transportVesicles To Golgi body

ER enzyme Produce Oil

and protein bodies

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ة� مي لأر� دوي, ي� hكة� الأ ي, واع الش> �Lن ا�Types of ER

Smooth ER Smooth ER 1- manufactures lipids, 1- manufactures lipids, 2- contains enzymes that detoxify 2- contains enzymes that detoxify certain poisons, certain poisons, 3- transports carbohydrates, 3- transports carbohydrates, lipids, and other non-proteinslipids, and other non-proteins..

Rough ERRough ERManufacture proteinsManufacture proteinsthese tubulesthese tubules

are studded withare studded with ribosomeribosome

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•ER domains produces oil bodies and protein bodies.

ة�• ي ب� ي رون� ة� والت, ي سام الدهب� ح, ة� الأ� مي لأر� دوي, ي� hكة� الأ ي, ج? الش> ت� ب£ Vئ•ER enzymes produce seed

storage proteins .ور• د� ن? الي, ي ة� ت,روئ� مي لأر� دوي, ي� hكة� الأ ي, مات� الش> ن� ر£ ت� hج? ا ت� ب£ Vئ

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Golgi ApparatusGolgi Apparatus ى ولج, هار� ح, ى ج, ولج, هار� ح, ن? هما:ج,Lي يÀن? مخدذ ي, Àبرك ات� ت� ن? هما:ذ�Lي يÀن? مخدذ ي, Àبرك ات� ت� ذ�

طة�5-15 ب, ة� المرن� ي ش> غ� من? الأ�لطحة� ة� المق� ي ن�� شطة� الوعا ن, والمي�

Cisternae((ة� ضلأت� الكروي د من? الحوي رة� والعدي� ت الضغ�

)Vesicles(

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Golgi ApparatusGolgi Apparatus ى ولج, هار� ح, ى ج, ولج, هار� ح, ) ج, ف� ائ� �))الوط ف� ائ� �)الوط

receive newly synthesized receive newly synthesized proteins and lipids proteins and lipids from ER and direct them from ER and direct them to either cell surfaceto either cell surface or vacuole. or vacuole.

The Golgi body isThe Golgi body is a carbohydrate factorya carbohydrate factory

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Cisternae

Vesicles

From ER

to

to

receive newly receive newly synthesized synthesized proteins and proteins and lipids lipids from ER and direct from ER and direct them them to either cell to either cell surfacesurface or vacuole. or vacuole.

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Vacuoles areVacuoles are::

fluid-filledfluid-filled compartmentscompartments

Usually occupy Usually occupy more than 30% more than 30%

of the cell volume of the cell volume and can approach 90%. and can approach 90%.

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FunctionFunctionOf VacuolesOf Vacuoles : :

They InvolvedThey Involved inin::

Digestion: acid Digestion: acid hydrolaseshydrolasessuch as such as proteases, proteases, nucleases,nucleases,lipases.lipases.

Defence againstDefence against microbes: toxicmicrobes: toxic

compounds such ascompounds such as phenols, alkaloids,phenols, alkaloids,

cell wallcell wall enzymesenzymes

and latexes.and latexes.

SequestrationSequestration of toxicof toxic

compounds: compounds: HeavyHeavy

metals and oxalate metals and oxalate (calcium crystals).(calcium crystals).

PigmentationPigmentation : :AnthocyaninAnthocyanin

pHpH and ionicand ionic

homeostasishomeostasis

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Plant cells contain at least two different vacuole systems:

Storagelytic

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TheThe NucleusNucleus

FunctionFunction

Nucleus contains mostNucleus contains most of the cell’s geneticof the cell’s genetic

informationinformation

and serves as theand serves as the center of regulatorycenter of regulatory

activity.activity.

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The Nucleus

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NucleusContain:

The nuclear envelope The nuclear envelope (two bilayer membranes (two bilayer membranes and perinuclear space) and perinuclear space) functions: Genetic material functions: Genetic material

separation from cytoplasmseparation from cytoplasm . .Controls nucleocytoplasmicControls nucleocytoplasmic exchange by meansexchange by means

of nuclear poresof nuclear pores

The nuclear poreThe nuclear pore complex functioncomplex function

both as molecular sievesboth as molecular sieves and as active transportersand as active transporters

The nucleolusThe nucleolusis not membraneis not membrane

boundedbounded

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The Nucleus

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The Nucleolus

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I-Introduction

دمة�88 مق�8888

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1- The use of energy from sunlight by photosynthesis is the basis of life on earth. ,ب ي, و س88 �ى ه88 وئ88 ل الض� ي88 مب> ة� الت� طة� عملي88 واس88 م88س ن, غ88ة� الش> ش> ن? ا� ة� م88 دام الطاق�88 خ� ت� س88 hرض�ا اة� على الأ� الحي2- The overall process whereby plants, algae and prokaryotes directly use light energy to ynthesize organic compounds is called photosynthesis كاب, و الطخالات� وال اي�� ي, واسطة� الب� رة� ن, اش> ة� مي, ي ون� ة� الض� دام الطاق� خ� ست� hة� ا عملي

�ى وئ ل الض� ي مب> ة� الت� شمى عملي ة� ب� وي ع المواذ العض� ي ضب� ة� لب� ولي ات� الأ� ي� ن

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. Photosynthesis is a biological oxidation-reduction

process

ال ت�ر� ج� hسدة� والأك ى الأ� ب� مل عملب ش> ة� ب� ي ولوح, ت ة� ن" �ى هى عملي وئ ل الض� ي مب> ة� الت� عملي

Electron acceptorات� لكت�روي� hل الأ ي, ف� Electron مشي�donorات� لكت�روي� hج الأ ماي��

Electron acceptorReducedل ت�ر� ح� ات� ي لكت�روي� hل الأ ي, ف� مشي�

Electron donoroxidized سدك و� ات� ن لكت�روي� hج الأ ماي��

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In case of oxygen-evolving (oxygenic) photosynthesis.?ن ي888 كس88خ, ل888أ� ة�88 ل88888888 ى المط8ل888888ف�8 � وئ888 ل الض�8888888 ي م8ب8> ة�88 الت�8 ا8لة�88 عم8لي ى ح8888888 ف�8888888888888888

Water servesAs the reductantWater is oxidized

Electrons ReleasedAnd transferredTo carbon dioxide

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In case of sulfur-evolving (anoxygenix) photosynthesis ب� Lي ر لكت88888888, ة�88 ل88888888 ى المط8ل888888ف�8 � وئ88 ة�88 الض�8888888 ا8لة�88 عم8لي ى ح8888888 ر8ف�8888888888888888 خ�ض�88888888888 ب� الأ�Lي ر ي� ا88 الكت88888888, ر8 كت�8888 ى ي8888888888888888, ما88 ف�8888888888888888 ك8888888888888

HydrogenSulfideElectrondonor

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Photosynthesis is: two phases takes place in different regions of the chloroplast ?ن ن? م88888888 ي88888888 لق� ت� ن? مح� ي88888888 ئ�� ر� ى ج, م ف�88888888 ت�88888888 ن? ن� ي88888888 ات� مرحلي� ى ذ� � وئ88888888 ل الض� ي88888888 مب> ة� الت� راءعملي88888888 ض� دات� الخ� ي لأسب� الي,

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Carbon linked reaction

Light dependent

reaction

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Photosynthesis involves two process: م8ل ش88> ى ب888888888888888� � وئ88 ل الض�8888888 ي م8ب8> ة�88 الت�8 ن?عم8لي ي8 ي� عم8لب881. The light reaction: produce O2, ATP and NADPH. لاع ق� ج88888?ت888888888888888� ت� ب�88 و�888 ئ88888 الض�88888882. The carbon-linked reactions (Calvin Cycle):

produce carbohydrates.درات� نL,وهي888 ج88888? الك88ر ت� ب£88 V8888888888888888ن? ئ ي8 ا8لق� ذورة� ك888888888888888و� اعل الض� ق� ت� ون? ,Lن د الكر �ى اكشي ئ� ا ال ي> ت�ر� ج� hب� وا ي ب" ي> VنAdenosine tri phosphate

Reduced NicotineamidAdenine dinucleotide phosphate

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Photosynthesis encompasses:a complex series of reactions that involve

طوات� هى �ى عدة� خ� وئ ل الض� ي مب> ة� الت� مل عملي ش> :ب�I- Light dependent reaction (Thylakoid membrane)1- light absorption و�888 ض8888888اض الض�8888888 اhمب�2- energy conversion �88ة ح888888و88ل الط8888888اق� ي8888888888�3- electron transfer ات� ر8وي� لكت�88888888 hا8ل الأ ق�88 ي� ن88£ hاII- Carbon linked reaction (Stroma) multi steps enzymatic pathway that converts CO2 and water into carbohydrates. �88ة مي88888 ن ر£ ت888� دة� خ�ط88888888و888ات� ا� ع88888888ة�88 ي دران��8 نL,وهي88 ر و888اذ ك888888888888888 لى م88 hون? ا,Lن د الك88ر كش8888ي �ى ا� ئ� ا8 ح888888و88ل ي888888888888888> ي8888888888�

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ب� ي ب" ي> Vالن ت�ر� ج� hواCO2

stroma

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Light Absorption and Energy Conversion

ة� حول الطاق� و� وي� ضاض الض� مب� hا

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Light has properties of both particles and waves. ات� ن� ي�8 ر� ص الخ888888888, و�888 خ�ض8888888888اي� ل8كÞ الض�8888888 مي� ن8888ة�88 ي ون888� ات� الض�888888 والموح8,Each quantum of light, or photon, contains energy. �888و م م8ن? الض�888888888 ت� و8ان��8 ل ك888888888888888 ك8888888888888

س88ا8وي ة�88 ب888888888888888� اق� و88ي عل888ى ط888 V88888ح88ت :يE = h.v

E = h x c/λ x NA

Where E: is energy of photon?ون و88ن� ة�88 الق� اق� ط888H: is the Planck constant (6.6 X10-34 J s)Þك ل88أئ8� ب� ي888888888888888, ا8ي88, ي888888888888888>V: is the frequency of the radiation و�888 رذذ الض�888888 ت8888888888888888�C: is the velocity of the light (3 X 108 s-1( و�888 ش88888888888ر888عة�88 الض�888888Λ: is the wavelength of light. الط88888و88ل الموج,ى88NA: is Avogadro Number=6x1023 ا8ذرو و8ح8, ف� ر88ق�م88 ا�

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Visible spectrum range between 400 and 700 nm. ?نÀي �ى ئ, ف� المرئ� ت�راوج الطي ومت�ر700-400ي ان� ي�

Dark red light (700 nm) contains 170 kJ/mol photons Calculate?

Quiz: The energy produced by two photons with a wave length of 500 is equal to?

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Light is absorbed by pigment molecules. ا ت� ع� واسطة� الصي و� ن, ص الض� مب� ن

In green plants, light is collected primarily by chlorophylls, ل ي واسطة� الكلوروق� و� اساسًا ن, ص الض� مب� راء ن ض� ات� الخ� اي�� ي, ى الب� ف�pigments that absorb light at a wavelength below 480 nm and

between 550 and 700 nm. ل من? ق� ى الأ� ي الطول الموج, و� ذ� ص الض� مب� ات� ن� ع� يÀن? 480الصي, ى ئ, ت�راوج طولة الموج, ي ي ومت�ر و الد� ان� ومت�ر700-550 ي� ان� ي�

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ع2 رف� و� ت� ات� الض� ي� لكت�رون?-كوان�£ hة� الأ طاق�وي• لى مشت� hا

ة� • على من? الطاق� ا�ة� ارة� الف�رذي ي�> hالة� الأح(

Single excitation state

•8- The excited• molecule my

•Loss an electron•To an electron •Acceptor Molecule

ة�• ي ون� ة� الض� حول الطاق� ي�ة�• ي ن�� ا مي ة� كت لى طاق� hا

1- Light is absorbed by pigment molecules

ات� ي� ص كوان�£ مب� واسطة� ن� و� ن, ة� الض� غ� الصي,لكت�رون? 3 hعوذ الأ - وت�

لى• hاموذ • حالة� الح�ى حدوذ • درة ف� من? ق� ة�9-10 ر� ي ن�� ا من? الي>

Ground state4- �88ة غ�88888 ص الصي888888, مب� ن? ن888888888888888� خ888888دت> ا� م وي� ت� عد الكوان�� ر ت, ج� م ا� ت� ة� كوان�� ع طاق� ق� ت�رت�� ول ق� لى حالة� الأ� hكت�رون? ال hة� الأ ي ن�� ا ارة� الي> ي�> hكت�رون?5 الأل hعوذ الأ ولى - وت� ارة� الأ� ي�> hالة� الأالى حFirst excited

state (single stateموذ لى حالة� الح� hعوذ ا و ت ا�

صة� 6 ة� الممب� هر - والطاق� �ظ ل ي� ى ئ, ف� ي� ح� ى ضورة� لأ ي� د ف� ق� ق� وت� ا�ة� عاغي ش> hة� ا طاق�

Radiation energy )Flourescence(لورة� و الق� ا�

ات� -7 ع�88888 ن? الصي888888, À88ي ة�88 ئ888888888888888, ل الط8888888اق� ق� ي� ب£88 V888888888888888دة� وئمساعال• ل غن? ي الكلوروق�ن? • ي ق� الرئ� ïن طر

(Resonance)

•9 -Produce strong •oxidant (P680)• provide the

• oxidizing power

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لى hكت�رون? ال hلأ عوذ ا� دما ت غي�لى حالة� hو ا موذ ا� ن? حالة� الح� hا ة� ق� ارة� الف�رذي ي�> hالأ ة� طلف� لكت�رون? المب� hة� الأ كالطاق� ش> د� عدة� ا� ح� ا� ي�

The energy Is released

as heatخرارة�ة� ك د الطاق� ق� ق� ت�Flourescenceلورة� الق�

The transfer of energy

From one molecule to another ة� ال الطاق� ق� ي� ن£ hلىا hة� ا غ� ريمن? صي, ج� ا�

The excited molecule my

Loss an electronTo an electron Acceptor Moleculeة� ي ون� ة� الض� حول الطاق� ي�ة� ي ن�� ا مي ة� كت لى طاق� hا

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9- Production of strong oxidant (P680) provide the

oxidizing power سدة�ك ة� مو� غ� اج? صي, ي� ن�£ hا P680

to remove electrons from water

(Photoxidation of water(ماءن? الات� م لكت�روي� hالة� ا ر� hلماءاة� ل ي ون� كسدة� الض� الأ�

reduction of NADPto NADPH ال ت�ر� ج� hاNADP لى hاNADPH

Photophosphorylation

of ADPTo ATP

ة� ي ون� شف�رة� الض� ADP لمركب, الف� لى hاATP

88

Heat1

23

Molecule(Pigment)

Energy transfer

Triplet

4Electron acceptor

Charge separation

PhotochemistryPhotochemistry

91

9- Production of strong oxidant (P680) provide the

oxidizing power سدة�ك ة� مو� غ� اج? صي, ي� ن�£ hا P680

to remove electrons from water

(Photoxidation of water(ماءن? الات� م لكت�روي� hالة� ا ر� hلماءاة� ل ي ون� كسدة� الض� الأ�

reduction of NADPto NADPH ال ت�ر� ج� hاNADP لى hاNADPH

Photophosphorylation

of ADPTo ATP

ة� ي ون� شف�رة� الض� ADP لمركب, الف� لى hاATP

96

The antenna funnels energy to the reaction center.The initial energy transformations in photosynthesis take place at specific sites in the photosynthetic membrane, known as reaction centers.Reaction centers are integral membrane protein complexes involved in conversion of light energy into chemical products.In light PSII functions as a water-plastoquinone oxidoreductaseP680 release electron topheophytin and to plastoquinin A (PQA)to produce plastosemiquinone (PQA-) plastosemiquinone (PQA-) transfer the electron toplastoquinin B (PQB)to produce semiquinone (PQB-)A second electron released from P680 to PQA.The second electron transfer from PQA- to PQB- to produce fully reduced PQB2-.fully reduced PQB2- takes up two proton from stroma yielding plastoquinol PQBH2.Plastocyanin is a soluble protein that links cytochrome b6f (cyt b6f) and photsystem I (PSI).PSI functions asa light dependent plastocyanin-ferredoxin oxidoreductase.Electrons from PSI are transferred to NADP+ in the stroma in a reaction requiring ferredoxin and ferredoxin-NADP+ reductase.

97

plastoquinin cytochrome b6f

Plastocyaninferredoxin-NADP+ reductase

ferredoxin

98

The efficiency of photosynthesis �ى وئ ل الض� ي مب> ة� الت� ة� عملي hا كق�

is determined by the quantum yield م ت� د الكوان�� عاي� در ت, ق� ت�

(molecules of O2 produced per photon absorbed) �88ة مي88 صوه8ى ك888888888888 ب� V8888ب ون? م8888 و88ن� كل ف�888888888888888 ة�88 ل8888 ح888888, Vت ن? المب�8 ي888 كس88خ, (الأ�

100

pigments and structure of photosynthetic

apparatus ل ي مب> هار� الت� ب, ج, ركي ات� وت� ع� صي, �ى وئ الض�

101

II- Other pigmentsري ج� ات� الأ� ع� الصي,

1 -CAROTENOIDSات� ي� ب الكاروئ� 2-phycobilinsات� ي� لب ي كون" ي الف�

β-carotene?ن ي ا كاروئ� ي� Àب ئ" α-carotene?ن ي ا كروئ� الق� Lycopene?نÀي كوئ, اللي Xanothphyllل ي وق� ت> ن�£ الر�

Photosynthetic pigments

�ى وئ ل الض� ي ات� الت�مب> ع� صي,

I- Chlorophyllل ي الكلوروق�II- Other Pigmentsري ج� ات� الأ� ع� الصي,

102

I- Chlorophyllل ي8 الكل88888و888روق88�A- Chlorophyll molecule containلىع وي Vحت ل ي ي ي� الكلوروق� ر� :ج,

1- a tetrapyrrole ring (porphyrin) ر8ول ت888 ر8ا ي888888888888888" ت�8 V888888888888888ة�88 ي حل888ف�82- phytol tail. ت�و88̀ل ي88 ل من? الق�Lئ ذ�83- Chlorophyll binds a magnesium atom at the center. ى المركر� وم ف� شت ن ي� رة� مغ� د� ل ي, ي ط الكلوروق� ب, ت رن��The first committed precursor in the biosynthesis of chlorophyll is δ-aminolevulinic acid. Þك ي لون888� ي8 ف� ي ل هو888 حمص� ل888888888 ي8 لكل88888و888روق88� و88لد ل88888888 اول م88 ب�ى ب8 م88 الأ�

103

Mg atom

Phytol tail

Tetral pyrolering

(FourModified Pyrole Rings(

104

To capture light �888و ض8888888اض الض�8888888 مب� hل88888888888أ plant required an antenna. ل ي8 ات� الكل88888و888روق88� كو88ي� حد م8888 ا88 وهو888 ا� ي� ب88 ي� ن88£ لى ا� hات� ا ي, اج? الب�88 ح88ت�88888 ي

The antennae of plants 88ا ي� ب88 ي� ن88£ الأ�consist of a large number of protein-bound chlorophyll molecules ?نكو88ن? م ي�8 ن888888

ب�ى ب ر8وئ88� ل الت8888, ي8 دذ من? الكل88888و888روق88� ع88888888

that absorb photons and transfer their energy to the reaction center complexل ي ى ا8لكلوروق� اعل ف� ق� لى مركر� الي� hها ا ت� ل طاق� ق� ي� و� ون ات� الض� وي� ون� ص ف� مب� ن

.

105

PS IIPS I

ا ي� ب ي� ن£ الأ�اعلمركر� ق� الي�

106

1 -Carotenoidsات� ي� ب الكاروئ�

107

1 -CAROTENOIDSFunctionsات� ي� ب ف� الكاروئ� ائ� �وط

in light absorption

absorb light between 400-500nm و� ص الض� مب� -400ن� ومت�ر500 ان� ي�

photo protectionسدة�ك ة� من? الأ� الحماية� ي ون� الض�

Responsible forThe orange-yellowColor observed

In plant ?وانل لة� غن? الأ� مشو�ة� الي ق� رت�� الضف�راء- الت,

Absorb and transfer

Light energy To

ChlorophyllMolecule

ة� ل الطاق� ق� ي� Vص ون مب� لن� ي لى الكلوروق� hة� ا ي ن� و� الض�

108

1- Carotenoid Absorb light between 400-500nm و�888 ص الض�888888 مب� ر5008-400ن88888888888888� ومت�888 ان88� ي8888888888�

109

superoxide radicals (.O2-)

2- photo protection In the absence of other acceptors electrons can be transferred from PSI to oxygen to form superoxide radicals (.O2-) Which damage plantات� ي, الب� ارة� ي, كون? مواذ ض� ن? مما ي ي كسخ, لى الأ� hول ا �ى الأ� وئ ام الض� �ط ها من? الب� ن� hا ات� ق� لكت�روي� hلأت� الأ ي, ف� ى مشي� اف� ات, ي, ي8 ى حال غ� ف�

Mehler reaction

110

2 -Phycobilins Pigmentsات� ي� لب ي كون" ي ات� الف� ع� صي,

play an important role in theabsorption of light energy in red algae and in Cyanobacteriaحمراءب, الطخالال ى و� ف� ة� الض� ص طاق� مب� ان� ي� كت�ر و ي, ان� والشي

Phycobilins are organized in complex protein-containing structures called

Phycobilisomes ى ها ف� ت, Àبرك م ت� �ظ ب� شومن للن ي كون" ي ق�

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2GAP

1GAP

1GAP

1 GAP

1 2

3

1

12

10

2

9

87

64

3

11

13

5

1GAP

Carbon llinked reactionFrom L.D.R From L.D.R

115

GENERAL INFORMATION• Aldehyde• Keton• Kinase• Dehydrogenase• Epimarase• Ismerase aldehyde keton• Transketolase• Aldolase• Ulase• Ose

116

The C3 carbon fixation cycle pathway known as

CALVIN CYCLEThe enzyme that Catalyze thisReaction Is RUBISCO

The first productIn these plants is

C3 (3- PGA)

The Calvin cycleProceed through13 steps In three phases

All of the 13 enzymesRequired in Calvin cycleLocated in Stroma

The carboxylation

The reduction

The regeneration

Conversion of 3 CO2 and3 RUBP to 6 3-PGA

Conversion of 6 3-PGATo 6 GAP Require 6ATP and 6 NDPH

Conversion of 5 GAPTo 3 RUBP

Require 3 ATP

This enzyme catalyzesTwo reactions

carboxylation

oxygenation

Most plantsAre C3

=9 ATP And

6 NADPH

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1-) Ribulose-1,5-bisphosphate carboxylase/oxygenase3 Ribulose-1,5-bisphosphate + 3 CO2 + 3 H2O →6 3 -

phosphoglycerate+ 6H+2- ) Phosphoglycerate kinase 6 (3-Phosphoglycerate( + 6 ATP 6 (1,3-bisphosphoglycerate( + 6

ADP3-) glyceraldehyde-3-phosphate dehydrogenase 6 (1,3-Bisphosphoglycerate( + 6 NADPH + 6 H+ →6 glyceraldehye-

3-hosphate + 6 NADP+ + 6 Pi4)Triose phosphate isomerase Glyceraldehyde-3-phosphate →dihydroxyacetone-3-phosphate5) Aldolase Glyceraldehyde-3-phosphate + dihydroxyacetone-3- phosphate

→ fructose-1,6-bisphosphate6- ) Fructose-1,6-bisphosphatase Fructose-1,6-bisphosphate + H2O → fructose-6- phosphate + 3

Pi

118

7( Transketolase Fructose-6-phosphate + glyceraldehyde-3-phosphate → erythrose-4-phosphate + xylulose-5 phosphate8 ) Aldolase

Erythrose-4-phosphate + dihydroxyacetone-3-phosphate → sedoheptulose-1,7-bisphosphate

9) Sedoheptulose-1,7,bisphosphatase Sedoheptulose-1,7-bisphosphate + H2O → sedoheptulose-7-phosphate + 2 Pi(10Transketolase Sedoheptulose-7-phosphate + glyceraldehyde-3-phosphate → ribose-5-phosphate + xylulose-5-posphate(11 Ribulose-5-phosphate epimerase

Xylulose-5-phosphate → ribulose-5-phosphate 12 )Ribose-5-phosphate isomerase Ribose-5-phosphate → ribulose-5-phosphate(13 Ribulose-5-phosphate kinase Ribulose-5-phosphate + ATP → ribulose-1,5-bisphosphate +6 ADP + 6 H+

120

C4 plant

121

The C4 carbon

The enzyme that Catalyze thisReaction Is PEPcase


C4 (Oxaloacetic acid

•To avoid oxygenation,• C4 plants •contain distinct CO2 fixation •enzymes and have a specialized •foliar anatomy (Kranz anatomy).

These plants involving Two different Types of Chloroplast-Containing cells

This enzyme catalyzesone reactions only

carboxylation

These plants involveMaiz, Sugarecane

And numerousTropical grasses

Mesophyll cells

Bundle sheath cells

Where CO2Fixed by PEPcase

To C4 acids

Where C4 Acids Are DecarboxylatedTo CO2 Calvin cycle

122

Diagram of leaf structure. Note the arrangement of tissue layers within the leaf.

123

Mesophyll cellsCO2 C4 acids

Bumddle seathC4 acid decarboxylated toCO2 and Pyruvate

124

Enzyme

125

CAMCrassulacean Acid Metabolism

126

The CAM plants

The enzyme that Catalyze thisReaction Is PEPcase


C4 (Oxaloacetic acid)

•CAM plants develop•Temporarily strategy

•)stomatal•Opening at night

At night 1- CO2 is fixed by PEPcase2- forming OAA3- OAA convert to Malate4- the Malate is storedIn the Vacuole

This enzyme catalyzesone reactions only

carboxylationAt light period1- Mate is Transported out The vacuoleMalate is Decarboxylated toCO2 and PyruvateCO2 fixed by RUBISCO (Calvin)

127chloroplast

vacuolecytocol

129

Phosphenol pyrophate

chloroplast

130

6CO2+6RuBP=30 C atoms 6RuBP (6*5=30)+ 1 glucose (6 C atoms)

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COMPENSATION POINT• when the gas exchange for two physiological process (photosynthesis and respiration )

• is equal ,• the environmental factors are at a level known as the compensation point.

• at the compensation point, • Plants:• do not grow (increase in dry matter),• but they do remine alive

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6 3-PGA

94 3

85

102

1

2 CO2carboxylation

oxygenation

137

C3 C41- photorespiration Yes No1- CO2 compensation point (µl CO2/l)

20-100 0-5

2- Temperature optimumPhotosynthesisRUBISCOPEPcase

20-2520-25----------------

30-45------------30-35

3- Quantum yield as a function of temperature

declining steady

4- Transpiration ratio 500-1000 200-3505- Light saturation (µ mole photons)

400-500 Does not saturate

A comparison of significance features of C3 and C4 plants

144

photosynthesis

Light reaction Carbon reaction

ETC C3 C4 CAM

ATP

NADPH

Carbohydrates production in chloroplast

Sucrose production in Cytosol

145

C3 plants

The enzyme is RUBISCO

the first product is C3 compound (GAP)

The acceptor of CO2 is ribuolose 1,5, bisphosphate

C4 plants

The enzymes are

the first product is C4 compound which transferredto bundle sheath, Brock down, evolve CO2 for rubisco

The acceptor of CO2 is PEP

CAM plants

RUBISCO in bundle sheath

PEPase in mesophyll cells

The enzymes are

The acceptor of CO2 is PEP

RUBISCO at day

PEPase at night

the first product is C4 compound which transferredto Vacuole, Brock down, evolve CO2 for rubisco

CO2 reduction

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GLYCOLYSISThe CONVERSION

OF CARBOHYDRATESTO pyruvate

CITRIC ACID

CYCLE

The CONVERSION OF PYRUVATE

TO CO2 AND H2O

The PRODUCTION OF NADH AMD FADH2

ELECTRONTRANSFER

The TRANSFER OF ELECTRONS FROM

NADH AND FADH2TO O2

RESPIRATION

149

Respiration is a biological oxidation-reduction process

Oxidized toReduced to

Electrons transferred from carbohydrates (formed during photosynthesis) to NAD AND FAD to form NADH and FADH2 (during KREBs Cycle) and then the electrons subsequently transferred to O2 to form water and produce ATP

150

Respiration)The oxidation of

Sucrose (Proceeds in

a series of reactions

1 -Glycolysis in

)cytoplasm and plastid

2-The citric acid cycle

In matrix ofMitochondria

3 -Electron transferIn Inner membrane of mitochondria

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2-The citric acid cycle

Electron transfer

152FermentationFermentation

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Glycolysis

The first stage of respiration is the conversion of storage carbohydrates to the pyruvate

The reactions catalyzed by enzymes located in the cytosol of the cell and not required oxygen

Glycolysis divide in two steps

1-Conversion of storage Carbohydrates toFructose1,6-bisphosphate

2-The conversion ofFructose1,6-bisphosphateTo pyruvate

157

Citric acid cycleOr KREBS cycle

Or TCC

The second stage of respiration is the complete oxidation of Pyruvate to CO2 +H2O

The enzymes of citric acid Cycle are located in the mitochondria (Matrix(

159

The Citric Acid Cycle• However, not every sucrose molecule is completely

oxidized in this manner. Many intermediates are diverted to produce carbon for important cellular compounds.

162

3 -electron transfer

The transfer of electrons

from NADH and FADH2 to Oxygen to produce H2O

163

12

3 56 74

From KREBs cycle

164

GLYOXYLATECYCLE

THE CONVERSION OF LIPIDSTO GLUCOSEBY INTERACTIONBETWEENGLYOXYSOMES, ANDMITOCHONDRIA

PENTOSEPHOSPHATEPATHWAY

THE CONVERSION OFGLUCOSE TO TETROSE ,

PENTOSE ANDNADPH IN THE CYTOSOL

OTHER RESPIRATORYPATHWAYS

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