IDENTIFICATION ON PHOTOSYNTHESIS

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                                         IDENTIFICATION ON PHOTOSYNTHESIS

S.NO

SCIENTISTS

YEAR OF DISCOVERY

DISCOVERIES

1

Van Helmont

(1648)

Increase in organic substances comes from water alone by growing a Willow tree that gains weight but soil loses only 2 ounces of the original weight

 

2

Stephen Hales

 

(1727)

Father of Plant Physiology, Plants obtain nourishment from air and light

3

Joseph Priestley

(1772)

Performed experiments with candle, mice and Mint plant and concluded that vegetation purifies the air

 

4

Jean-Ingen-Housz

(1779)

Confirmed Priestley’s experiment that oxygen released by the plants is possible only in light

5

Lavoisier

(1783)

Purifying gas produced by plants in sunlight is Oxygen (Phlogiston) and noxious gas produced by burning of candle (de Phlogiston) is Carbon di oxide

6

Desaussure

 

(1804)

Explained the importance of water in the process of photosynthesis

7

Dutrochet

 

(1837)

Explained the importance of Chlorophyll in Photosynthesis

8

Von Mayer

(1845)

Green plants convert solar energy into chemical energy of organic matter. 

9

Liebig

 

(1845)

Organic matter of plants was derived from CO2

10

Julius Von Sachs

 

(1854)

Discovered that product of photosynthesis was starch. Green substance (chlorophyll) is located in special structures (Chloroplast)

11

T.W. Engelmann

(1888)

Plotted action spectrum of photosynthesis

 

12

Warburg

 

(1920)

Used unicellular green algae Chlorella for the study of Photosynthesis.

 

13

Van Neil

 

(1931)

Oxygen released during photolysis comes from water and not from CO2. He also conducted experiments in Purple green bacteria and demonstrated Photosynthesis.

 In Green Sulphur bacteria H2S is the Hydrogen donor which releases Sulphur instead of oxygen.

14

 

Emerson and Arnold

 

(1932)

Existence of light and dark reaction by flashing light experiments.

 

15

R. Hill

(1937)

Explained photolysis with the help of isolated chloroplasts and electron acceptors in the presence of light

 

16

Ruben and Kamen

(1941)

Used 18O radioactive Oxygen to prove that oxygen evolves from water

 

17

Arnon, Allen and Whatley

 

(1954) 

Used radioactive 14CO2 to show fixation of CO2 by isolated chloroplast

18

Melvin Calvin

 

 

 

(1954)

Used radioactive 14CO2 and traced path of carbon in the dark phase of photosynthesis or C3 Cycle

19

Emerson et al.,

 

(1957)

Reported existence of two photosystems

20

Hatch and Slack

(1965)

 

Reported C4 pathway and CO2 fixation in C4 plants

 

21

Huber, Michel and Dissenhofer

 

(1985)

Crystalized photosynthetic reaction centre of Rhodobacter and received the Nobel Prize in 1988

 

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