In Englemann’s experiment with Cladophora, bacteria accumulated near which regions of the spectrum, proving the role of these wavelengths in photosynthesis?
1. Orange and Violet
2. Green and Yellow
3. Infrared and Ultraviolet
4. Red and Blue
Subtopic:  Historical View: Experiments |
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Match the experiment with its contribution: 
List-I (Scientist) List-II (Contribution) 
A. Joseph Priestley 1. Light is essential for photosynthesis
B. Jan Ingenhousz 2. Role of \(O_2\)in burning a candle
C. Julius von sachs 3. Starch as product of photosynthesis
D. T.W. Engelmann 4. Action spectrum 
Codes: 
1. A-2, B-4, C-3, D-1
2. A-1, B-2, C-4, D-3
3. A-2, B-1, C-3, D-4
4. A-3, B-1, C-2, D-4
Subtopic:  Historical View: Experiments |
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Consider the given two statements:
Assertion (A): In the experiment where part of a leaf is enclosed in a KOH-soaked tube and the other half is exposed to air, the KOH-treated portion tests negative for starch, while the exposed part tests positive.
Reason (R): KOH absorbs CO₂, preventing photosynthesis in the enclosed portion, thereby proving that CO₂ is essential for starch formation.
Options:
1. Both (A) and (R) are True and (R) correctly explains (A).
2. (A) is True but (R) is False.
3. (A) is False but (R) is True.
4. Both (A) and (R) are False.
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What was the contribution of Julius von Sachs to plant physiology?
1. He discovered that plants absorb nitrogen from the air to synthesize glucose.
2. He identified mitochondria as the site of photosynthesis in plant cells.
3. He demonstrated that all plant cells, irrespective of color, can perform photosynthesis.
4. He provided evidence that plants produce glucose and store it as starch.
Subtopic:  Historical View: Experiments |
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T.W. Engelmann:
1. described a first action spectrum of photosynthesis
2. provided evidence for production of glucose when plants grow
3. showed that it is only the green parts of the plant that can release oxygen
4. first showed that oxygen evolved by the green plant comes from water, not from carbon dioxide
Subtopic:  Historical View: Experiments |
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What was the significance of Jan Ingenhousz’s experiment with aquatic plants?
1. It demonstrated that green parts of plants release oxygen only in the dark.
2. It proved that plants release CO2 during photosynthesis.
3. It showed that sunlight is essential for oxygen release in photosynthesis.
4. It revealed that non-green parts of plants perform photosynthesis more efficiently.
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Which reagent can be used to determine the essentiality of CO2 for the process of photosynthesis.
1. KOH
2. K2Cr2O7
3. Starch
4. Iodine tincture
Subtopic:  Historical View: Experiments |
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Match the Scientists given in Column-I with their contribution in Column-II and select the correct match from the codes given:
Column-I Column-II
A. Jan Ingenhousz P. Provided evidence for production of glucose when plants grow
B. T. W Engelmann Q. Described the first action spectrum for photosynthesis
C. Julius von Sachs R. Showed that sunlight is essential for photosynthesis
D. Cornelius van Neil S. Inferred that oxygen evolved in photosynthesis comes from water and not from carbon dioxide
Codes
A B C D
1. R Q P S
2. Q R S P
3. P S R Q
4. S P Q R
Subtopic:  Introduction | Historical View: Experiments |
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The given diagram represents Engelmann’s experiment using a filamentous alga and oxygen-using bacteria. What conclusion was drawn from this experiment?
      
1. Oxygen is released uniformly along the algal filament during photosynthesis.
2. Bacteria aggregated where oxygen concentration was lowest.
3. Maximum bacterial accumulation occurred in regions where the alga received light most effective for photosynthesis.
4. The experiment proved that bacteria produce oxygen required for algal photosynthesis.
Subtopic:  Historical View: Experiments |
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Which of the following scientists discovered oxygen?
1. Joseph Priestley
2. Jan Ingenhousez
3. Cornelius van Niel
4. T.W. Engelmann
Subtopic:  Historical View: Experiments |
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