Red drop & Emerson's effect

1. BACHELORS OF SCIENCE 3RD YEAR
SUBJECT: BOTANY
TOPIC : RED DROP & EMERSON’S EFFECT,CONCEPTS
OF TWO PHOTOSYSTEMS
CREATED AND PRESENTED BY : ATIF ALI ZAKIR

2. ABSORPTION SPECTRUM & ACTION SPECTRUM
 ONLY VISIBLE LIGHTS TAKE PART IN THE PHOTOSYNTHESIS
 CHLOROPLAST PIGMENTS ABSORBS LIGHT OF CERTAIN SPECIFIC
WAVELENGTH
 THE AMOUNT OF ABSORPTION OF DIFFERENT WAVELENGTH
OF LIGHT BY A PARTICULAR PIGMENT IS CALLED AS
ABSORPTION SPECTRUM OF THAT PIGMENT
 CHLOROPHYLL-A ABSORBS MAXIMUM IN THE BLUE AND RED
REGIONS OF THE LIGHT SPECTRUM
 THE EEFECTIVENESS OF DIFFERENT WAVELENGTHS OF LIIGHT
UTILIZED IN THE ACTION OF A PROCESS IS CALLED AS ACTION
SPECTRUM,IN CASE OF PHOTOSYNTHESIS ,IT IS UTILIZED IN
CO2 FIXATION O2 PRODUCTION & NADP REDUCTION
THEREFORE IT IS CALLED AS THE ACTION SPECTRUM OF
PHOTOSYNTHESIS

3. ACTION SPECTRUM & ABSORPTION SPECTRUM

4. RED DROP AND EMERSON’S EFFECT
 IT GIVES AN IDEA ABOUT THE RATE OF PHOTOSYNTHESIS
AT DIFFERENT WAVELENGTHS
 QUANTUM YEILD: AMOUNT OF OXYGEN RELEASED PER
QUANTUM OF LIGHT ABSORBED
 RED DROP: A SUDDEN DECLINE IN THE RAT OF
PHOTOSYNTHESIS AFTER 68Onm
 P.S. at 700nm= 10 Q.Y (indivivually)
 P.S at 653nm= 52-53 Q.Y (indivivually)
 P.S at 700 & 653nm= 72 Q.Y (Together)
EMERSON’S ENHANCEMENT EFFECT
 HERE THEY CONCLUDED THAT IT IS BECAUSE THAT THERE
ARE TWO PHOTOSYSTEMS WHICH ARE WORKING DURING
PHOTOSYNTHESIS
A.PSI-700
B.PSII-680

5. RED DROP AND EMERSON’S EFFECT

6. CONCEPT OF PHOTOSYSTEMS
CHLOROPLAST
HAVE PIGMENTS
P.S. ARE
CLUSTER OF
LIGHT
ABSORBING
PIGMENTS
P.S. CONTAIN 200
MOL OF CHL &
50 MOL.OF
CAROTENOIDS
ENERGY
TRAPPED BY CHL
& OTHERS
PIGMENT
CONVERGE INTO
TRAP CENTRE
i.e., PSI & PSII
PSI & PSII
COOPERATE
EACH OTHER
RESULT IN
FUCTIONING
PHOTOSYNTHES
IS
PRESENT IN
THYLAKOID
MEMBRANE OF
CHLOROPLAST

7. PHOTOSYNTHETIC PIGMENTS
PIGMENT SYSTEM I (PSI) PIGMENT SYSTEM II (PSII)
 IT IS MADE UP OF 200 -400
CHOLOROPHYLL –A
MOLECULES & 50 CAROTENOIDS
MOLECULES
 CHLOROPHYLL-B MOLECULES
IS LESS
 ITS REACTION CENTRE IS P700
 IT IS LOCATED ON THE OUTER
SURFACE OF THYLAKOID
 IN THIS SYSTEM ,MOLECULAR
O2 IS NOT EVOLVED
 IT PARTICIPATE IN BOTH
CYCLIC AND NON CYCLIC
PHOTOPHOSPHORYLATION
 IT IS MADE UP OF 200
CHOLOROPHYLL MOLECULES ,50
CAROTENOIDS MOLECULES
 CHLOROPHYLL-B MOLECULES IS
MORE
 ITS REACTION CENTER IS P680
 IT IS LOCATED ON THE INNER
SURFACE OF THYLAKOID
 IN THIS SYSTEM , MOLECULAR O2 IS
EVOLVED DUE TO THE
BREAKDOWN OF WATER
 IT PARTICIPATES ONLY IN NON
CYCLIC PHOTOPHOSPHORYLATION
 IT GIVES ELECTRON TO PS-I WHEN
NADP IS REDUCED TO NADPH + H
IN PS-I

8. PHOTOSYSTEMS-I AND II

9. CREATED AND PRESENTED BY
ATIF ALI ZAKIR
STUDENT OF MSC BOTANY II YEAR
SAFIA SCIENCE COLLEGE BHOPAL
U CAN FIND ME ON INSTAGRAM : @atif_ali_zakir