photosynthes

ANABOLIC REACTIONANABOLIC REACTION ENDERGONIC REACTIONENDERGONIC REACTION CORBOHYDRATES ARE PRODUCEDCORBOHYDRATES ARE PRODUCED O2 IS BIPRODYCTO2 IS BIPRODYCT

6CO2+12H2O6CO2+12H2O C6H12O6+6H2OC6H12O6+6H2O

OVERVEIW OF PHOTOSYNTHESISOVERVEIW OF PHOTOSYNTHESISOVERVEIW OF PHOTOSYNTHESISOVERVEIW OF PHOTOSYNTHESIS O2 AND CARBOHYDRATES ARE PRODUCEDO2 AND CARBOHYDRATES ARE PRODUCED

BRIEF PHOTOSYNTHESISBRIEF PHOTOSYNTHESIS

thylacoid

CHLOROPLAST

Periplastidial space

Inner membrane

Outer membrane

Lumen

STRUCTURE OF CHLOROPLAST

Chloroplast contains the pigments

Matrix is called STROMA Thylacoids embedded in stroma Group of thylacoids called

GRANA Dark Reaction : STROMA Light Reaction : GRANA Thylacoid membranes contain

1.PHOTOSYSTEM I2.PHOTOSYSTEM II

PHOTOSYSTEMSPHOTOSYSTEMS PHOTOSYSTEMSPHOTOSYSTEMS

CONTAINS 2 COMPONENTS:

1.ANTENA(LHC): It absorb radiant

energy & supplies it to reaction center.

2.REACTION CENTER: Converts the light

energy into chemical energy.

Reaction center in PS-I is P700.& in PS-II P680

MECHANISM OF PHOTOSYNTHESISMECHANISM OF PHOTOSYNTHESISMECHANISM OF PHOTOSYNTHESISMECHANISM OF PHOTOSYNTHESIS

1.LIGHT REACTION: NADPH & ATP are generated

from light. NADPH & ATP are called

ASSIMILATORY POWER

2.DARK REACTION: Formation of Carbohydrates

fromCO2 by utilizing

ASSIMILATORY POWER Both reactions were first

discovered by BLACKMAN in 1905.

LIGHT REACTIONSLIGHT REACTIONS

DISCUSSED UNDER 4 HEADINGS:1. HILL REACTION

2. EMERSON ENHANCEMENT EFFECT

3. PSI &PSII ELECTRONE TRANSPORT & PROTON TRANSLOCATION

4. PHOTOPHOSPORYLATION

1. HILL REACTION:

Photolysis of water

2H2O+2A------------2AH2+O2

States that O2 is released from water not from CO2

EMERSON ENHANCEMENT EFFECT

RED DROP: Drop in photosynthetic rate at higher

wave length of red light Increase in the Photosynthetic rate at

higher and lower wave length of light (650-680nm) when used simultaniously called as EEE

PSI & PSII

PSI &PSII ELECTRON TRANSPORT AND PROTON TRANSLOCATION

ELECTRONS MOVES ACROSS THE COMPLEXES IN THE CHLOROPLAST MEMEBRANE TO PRODUCE ASSIMILATORY POWER

PHOTOPHOSPHORYLATION DANIEL ARNON:First described Occurs according to the MITCHELL’S Chemiosmotic theory TWO TYPES: 1.CYCLIC ELECTRON TRANSPORT

2. NONCYCLIC ELECTRON TRANSPORT

CYCLIC ELECTRON TRANSPORT Electrons move in cyclic manner to generate ATP

NONCYCLIC ELECTRON TRANSPORT ELECTRONS MOVE IN A CLOSED CIRCUTE

DARK REACTION Occurs in stoma CO2 is reduced to form carbohydrates

by utilizing ASSIMILATORY POWER.

TWO PATHWAYS are identified. 1.CALVIN CYCLE(C3) 2.HATCH & SLACK PATHWAY(C4)

DARK REACTION

CALVIN CYCLE(C3) CO2 REDUCED TO FORM CARBOHYDRATES CO2 ACCEPTER IS RUBP FIRST PROCUCT IS 3-PHOSPHOGLYCERIC ACID 3PGA CONTAINS 3 CARBONS SO THE NAME C3.

STEPS:1. CARBOXYLATION PHASE

2. REDUCTION PHASE3. REGENERATION PHASE

CALVIN CYCLE(C3)

CALVIN CYCLECALVIN CYCLE CALVIN CYCLECALVIN CYCLE

HATCH&SLACK PATHWAY(C4)

B.CARBOXYLATION OCCURS IN 1500 SPECIES OF 19 FAMILIES THESE CAN GROW IN DROUGHT CONDITIONS LEAVES CONTAINS KRANZ ANATOMY FIRST PRODUCT CONTAINS 4 CARBONS SO

THE NAME IS C4 CYCLE

Am HriticI tell u About

C3 cycle

Let’s move to next page

KRANZ ANATOMY

HATCH & SLACK PATH WAY

C4 CYCLE1.PYRUVIC

ENZYMES

PEP DECARBOXYLAASE

MALIC ACID DEHYDROGENASE

MALIC ENZYME

PIRUVIC ACID DIKINASE

FACTORS EFFECTING PHOTOSYNTHESIS

1.EXTERNAL FACTORS2.INTERNAL FACTORS

EXTERNAL FACTORS: LIGHT TEMPERATURE CO2 CONCENTRATION O2 CONCENTRATION H2O

INTERNAL FACTORS CHLOROPHYLL CONTENT INTERNAL STRUCTURE OF LEAVES ACCUMULATION OF END PRODUCT BLACKMAN’ LAW OF LIMITING FACTOR