Photo Synthesissisis Brooo

Question 1

Photosynthesis is, evolved

Light energy converted into
Why redox bro
Is also an ( reaction

Answer 1

A physiochemical or photo biochemical in which organic compounds ( glucose) are synthesised from inorganic raw material ( h2o,co2) in presence of light , O2
Chemical energy
Oxidation of h2 ( provided h+ and e ) during light reaction reduction of co2 ( accepts h+ &e ) during dark reaction
Anabolic ( synthesing ) & endergonic ( energy absorbing ) process

Question 2

Variegated leaf experiment explain
On testing
Molls half leaf experiment
Conclusion

Answer 2

Leaf that was partially covered with black paper and one was exposed to light
Photosynthesis occurred only in green parts of leaves in presence of light
Part of leaf is enclosed in test tube containing some KOH soaked cotton which absorbs co2 while the other half is exposed to air
Shows that co2 is required for photosynthesis

Question 3

Joseph Priestley (year), plant , conclusion
Jan Ingenhousz ( year) same setup but , showed
Also showed that

Answer 3

1770 , ,mint , plants restore to air whatever breathing animals and burning candles remove
1730-1799) in dark showed that sunlight is essential to plant process that somehow purifies the air
It is only the green part of the plants that could release oxygen

Question 4

J.V. Sachs year, provided evidence And it is stored as
Later studies showed that
Van Niel was , used showed that

Conclusion

Answer 4

1854 , for production of glucose when plants grow , as starch
The green substance in plants is located in special bodies within plant cells
Microbiologist , purple and green bacteria , photosynthesis is light dependent reaction in which hydrogen from a suitable oxidisable compound reduce co2 to carbohydrate
O2 evolved by green plant comes from h2o not from co2

Question 5

Van niel reaction
Ruben and Kamen year

Answer 5

2H2A + co2 = (light ) = 2A + CH2O + H2O ( H2A = suitable oxidisable compound or H- donar
1941 , used o18 (radioisotopic techniques) to show experimentally that o2 in photosynthesis released from water

Question 6

Photosynthesis take place
Within chloroplast there is
Membranous system responsible for ( reaction
Stroma

Answer 6

In green leaves of plants , also in other green parts of plant
Membranous system consisting of grana , the stroma lamellae , matrix stroma
( thylakoid ) = trapping the light energy, for synthesis of ATP and nadph ( light ,photochemical
Enzymatic reactions synthesis sugar , which in turns form starch ( dark , carbon

Question 7

Usually chloroplast align themselves
Parastrophe
epistrophe
Apostrophe
Photosynthetic pigments are

Answer 7

Along the walls of mesophyll cells
High intensity light,parallel to incident light /. Lateral walls
Low light intensity, perpendicular to incident light
Moderate light intensity ( random
Special molecules those absorb , transmit,reflect different colours of light from visible spectrum of sunlight

Question 8

Pigments appear,uses
Photosynthetic pigment
Leaf pigment can be separated ,result
chlorophyll colour,required,solvents

Answer 8

In colour which it reflects, uses colour it absorbs
Chlorophyll,carotenoids,phycobilins
Through paper chromatography, chromatogram
Green,light is required for synthesis,soluble in organic solvents

Question 9

Chl a , found, colour
Chl b
Structure of chlorophyll is
Head size , it is , character
Tail

Answer 9

Universal pigment , blue green
Euglenoids,green algae,higher plants ,yellow green
Tadpole like
Porphyrin , 15x15 A, hydrophilic, tetrapyrole structure with mg +nt in centre
Phytol (C20H39OH ) , 20 A, hydrophobic, remain embedded in lipid bilayer of thylakoids membrane

Question 10

Chlorophyll a
Chlorophyll b
Chlorophyll synthesis
Catalysed
Carotenes , colour, contains
Xanthphyll

Answer 10

C55H77O5N4Mg , ch3 group in pyrrol ring
C55H70O6N4Mg , CHO group in pyrrol ring
Succinyl CoA + glycine = protochlorophyll = chlorophyll ( light , 2H)
Iron fe
Yellow orange , carbon and hydrogen
Yellow , carbon and hydrogen and oxygen

Question 11

Common in plants
Fn of carotenoids
Phycobillins are soluble, tail
Types
Occur

Answer 11

Beta - carotene , lutein ( xanthophll )
Accessory pigments, protect chl a from photo oxidation
also protect by converting lethal nascent oxygen into unharmful molecular oxygen thus called shield pigments
Hot water soluble, mg and phytol tail
Phycocyanin = blue , phycoerythtin = red , allophycocyanin = light blue
In BGA and red algae

Question 12

PAR
Absorption spectrum
Action spectrum y axis
Maximum
T.w engelman used

Answer 12

Photosynthesis active radiation = 400-700 nm
Chl a shows maximum absorption at blue light then red light
Rate of photosynthesis, measured by O2 released
Red then blue
Green algae chadophra , in suspection of aerobic bacteria

Question 13

Light reaction / , include
Who worked (on)
Photo system
The LHC are made up of

Answer 13

Light absorption,water splitting,oxygen release,formation of high energy chemical intermediate like ATP and NaDPH
Emerson , Arnold worked on chlorella
The groups of photosynthesis pigments in thylakoids mem
200-400 molecules of pigments bound to proteins

Question 14

Photo phosphorylation
Non cyclic/ ,
Includes
Pathway
Moment of electron is

Answer 14

Synthesis of atp from ADP and inorganic phosphate (ip) with the help of light energy
Z scheme and splitting of water
Both ps 1, ps2 , occurs only in stroma thylakoids
Ps 2 => pheophytin => pheoquinone => cytochrome B6F => plastocynin => ps 1
Is downhill in terms of oxidation o redox potential scale

Question 15

Ps1 pathway
The splitting of water is associated with (located
Z scheme is formed
What not formed in cyclic

Answer 15

FRS to FD
PS2 , on inner side of membrane of thylakoids
When all the carries are placed in sequence on redox potential scale
No o2 evolved,nadph2 ( reducing power ) not formed
Only atp formed

Question 16

Chemiosmotic hypothesis proposed by ,
Step that cause a proton gradient to develop

As well as also

Answer 16

Peter Mitchell ( 1961) , atp synthesis is linked to development of proton gradient ( difference of proton h+ ) across thylakoids mem
Splitting of h2o molecule in lumen ( h+ ) in lumen
Plastoquinone is a H carrier so pheophytin uses H+ proton from stroma
Plastoquinone passes proton to lumen by transferring electrons to cytochrome B6F
NADP reductase enzyme use proton from stroma
A measurable decrease in pH in lumen

Question 17

ATP synthase enzyme consist of
The gradient is broken down due to
Chemiosmosis requires
Dark reaction or
What led to discovery of 3 carbon organic acid ( name ?? ( he used ??
In c3 plants Calvin cycle occurs in , first unstable compounds

Answer 17

CF0 is embedded in mem
Cf1 faces stroma
Movement of protons across mem to stroma through transmembrane channel of CF0 of ATP synthase
A membrane, a proton pump , a proton gradient , ATP synthase
Biosynthetic phase
The use of radioactive C14 by him in algal photosynthesis ( 3 - phosphoglyceric acid
Stroma , carboxy ketoribitol bisphosphate

Question 18

Calvin studied dark cycle in , Rubisco
Carboxylation is the , where co2 is utilised
Reduction involves utilising—- for reduction per co2 molecule
Regeneration involves
For every co2 molecule , for glucose

Answer 18

Green algae ( chlorella , scenedesmus ), Ribulose 1,5 bisphosphate carboxylase oxygenase )
Fixation of Co2 into stable organic intermediate , for carboxylation of RuBP ( ribulose bisphosphate- 5 carbon ketose sugar
Of 2 molecules of ATP for phosphorylation and 2 of nadph for reduction
1 AtP
3 ATP and 2 nadph , 12 nadph and 18 atp

Question 19

C4 pathway /
Most of c4 plants are , and adapted to environment
C4 plants eg
Anatomy

Answer 19

Hatch & slack pathway / dicarboxylic acid cycle ( dca cycle ) / co- operative photosyn
Monocots ( tropical grasses) which belong to gramineae & cyperacea, hot and dry
Sugarcane , maize,sorghum
Kranz ( wreath ) and is reflection of arrangement of cells

Question 20

Bundle sheath character

—— chloroplast +nt in leaf chloroplast of bundle sheath /, mesophyll chloroplast
First CO2 acceptor in c4 plants in mesophyll , second acceptor in bundle sheath cells
Co2 catalysted by in mesophyll cells

Answer 20

Having large no of chloroplasts
Thick walls impervious to gaseous exchange
No intercellular spaces
Dimorphic , kranz cells are large and without grana ( agranal) , small and with grana
Is PEP phosphoenol pyruvate (3C), RuBP (5c)
PEOcase which results in formation of OAA (4C)

Question 21

C4 plants total utilised ,
Are special because

Why

Answer 21

30 ATP , 12 NADPH
They have special type of leaf anatomy
Tolerate higher temperatures
Show a response to high light intensities
Lack a process called photorespiration so have greater productivity of bio mass
Because they have a mechanism that increases concentration of co2 at RubisCO enzyme site

Question 22

Mechanism reason
In c4 plants site of Rubisco activity, site of O2 evolution
C4 , C3 making sugar mechanism
Photo respiration/

Answer 22

Malic or aspiritic acid from mesophyll is broken down in bundle sheath cell to release co2
Bundle sheath cells ,mesophyll cells
C4&raquo_space; C3 twice ,
Photosynthetic carbon oxidation / C2 cycle / glycolate mechanism

Question 23

Photo respiration, occurs in ( organelles)
Rubisco has greater affinity , condition for photorespiration
RuBP converts into
It results in

Answer 23

The light dependent uptake of O2 and release of CO2 in green cells of C3 , chloroplast , peroxisome, mitochondria
For CO2 than O2 , high light intensity ( high O2 , low co2 ) , high temperature
One molecule of phosphoglerate ( 3C) , one molecule of phosphoglycolate ( 2c)
In release of co2 with utilisation of ATP

Question 24

The internal / factor

Internal factor are dependent on
Law of limiting factor proposed by

Answer 24

Plant factor , no,size,age and orientation of leaves , mesophyll cells and chloroplast , internal co2 concentration, the amount of chlorophyll
Genetic predisposition and growth of plant
Blackman’s (1905)

Question 25

Law of limiting factor
Limiting in clear sky , light limiting factor
There is linear relationship b/w
At higher light intensities

Answer 25

If a chemical process is affected by more than one factor , then it’s rate will be determined by factor which is nearest to its minimal value
CO2 , cloudy days , dense forest , shady plants
Incident light and co2 fixation at low light intensities
Gradually the rate does not show further increase as other factors become limiting

Question 26

Light saturation occurs at
Increase in incident light beyond a point
Conc of co2 in atmosphere , increase in ____ CO2 concentration can increase photos
Low light intensity respond to high co2 conditions

Answer 26

10% of full sunlight
Causes the breakdown of chlorophyll and a decrease in photosynthesis
Is very low (0.03-0.04%) , 0.05%
No plant C3,C4
Both C3,C4 show increase in plants

Question 27

C4shows saturation at, C3 response to increased co2 concentration
Current availability of Co2 is limiting for
Green house crops
Atmospheric co2 is not limited to

Answer 27

360 ulL-1 , 450 ulL-1
C3 plants
C3, tomato,bell peppers
C4 and submerged hydrophytes

Question 28

More sensitive to temperature
C4 respond to temperature, c3
Temperate , tropical high temperature

Answer 28

Dark reaction
Higher temperature (30-40 degrees) , much lower temperature ( 20 -25)
Tropical&raquo_space;> temperate

Question 29

Water stress causes
Water stress also makes leaves

Answer 29

The stomata to close hence reducing the co2 availability
Wilt, thus reducing the surface area and their metabolic activity