Experiments of Photosynthesis MCQ Quiz - Objective Question with Answer for Experiments of Photosynthesis - Download Free PDF

The correct answer is Statement-A is incorrect but Statement-B is correct

Explanation:

• A part of a leaf is enclosed in a test tube containing some KOH soaked cotton (which absorbs CO₂), while the other half is exposed to air.
• The setup is then placed in light for some time.
• On testing for the presence of starch later in the two parts of the leaf, the exposed part of the leaf tested positive for starch while the portion that was in the tube, tested negative. This showed that CO₂ was required for photosynthesis.

The correct answer is 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂ 

Explanation:

• Photosynthesis is a fundamental biological process by which plants, algae, and some bacteria convert light energy into chemical energy, storing it in the bonds of glucose (a type of sugar)
• The overall chemical equation for photosynthesis in oxygen-evolving organisms is as follows 6CO₂ + 12 H₂O → C₆H₁₂O₆ + 6 H₂O + 6O₂ 

The correct answer is Green portion

Explanation:

• A variegated leaf or a leaf that was partially covered with black paper, and exposed to light.
• On testing these leaves for the presence of starch it was clear that photosynthesis occurred only in the green parts of the leaves in the presence of light.

Correct Answer: T.W. Engelmann

Key Points

• T.W. Engelmann carried out the action spectrum experiment.
• Through this experiment, he deduced that the most photosynthetically active region will show the highest concentration of bacteria.

Additional Information

• Photosynthesis is the chemical process by which carbohydrates (organic molecules) are synthesized from inorganic materials like CO2 and H2O with the help of light energy which is trapped by pigments like chlorophyll.
• Oxygen is given out at the end of the photosynthesis process.

​

• Green plants, algae, and photosynthetic bacteria carry out the process of photosynthesis.
• Chlorophyll, carotenoids, and phycobilins are some of the most important pigments involved in the photosynthetic process.
• Chlorophyll pigments efficiently capture solar energy. 
• Chlorophylls absorb light in the violet, blue and red wavelengths of the light spectrum. This part of the light spectrum is also referred to as photosynthetically active radiation (PAR). It ranges from 400nm to 700nm.

Correct answer is Priestly

Key Points

• The Bell Jar Experiment.
  • J. Priestley (1772) carried out very interesting experiment on Bell jar, rat, pudina or mint and candle. He came to conclude that plants purify air (burning of candles), and gaseous exchange occurs during photosynthesis.
    Priestley observed that a candle burning in a closed space – a bell jar, soon gets extinguished.
  • Similarly, a mouse would soon suffocate in a closed space. He concluded that a burning candle or an animal that breathe the air, both somehow, damage the air. But when he placed a mint plant in the same bell jar, he found that the mouse stayed alive and the candle continued to burn.
  • Priestley hypothesized as follows: Plants restore the air which breathing animals and burning candles remove.
     

Correct Answer: T.W. Engelmann

Key Points

• T.W. Engelmann carried out the action spectrum experiment.
• Through this experiment, he deduced that the most photosynthetically active region will show the highest concentration of bacteria.

Additional Information

• Photosynthesis is the chemical process by which carbohydrates (organic molecules) are synthesized from inorganic materials like CO2 and H2O with the help of light energy which is trapped by pigments like chlorophyll.
• Oxygen is given out at the end of the photosynthesis process.

​

• Green plants, algae, and photosynthetic bacteria carry out the process of photosynthesis.
• Chlorophyll, carotenoids, and phycobilins are some of the most important pigments involved in the photosynthetic process.
• Chlorophyll pigments efficiently capture solar energy. 
• Chlorophylls absorb light in the violet, blue and red wavelengths of the light spectrum. This part of the light spectrum is also referred to as photosynthetically active radiation (PAR). It ranges from 400nm to 700nm.

Concept:

Oxidation reaction:

• Oxidation Reaction refers to a reaction in which either the addition of Oxygen takes place or the removal of Hydrogen takes place.
• It can also be said as the process of loss of one or more electrons by atoms or ions.
• Eg - H₂O gets oxidised to release O₂ {Removal of hydrogen}

Reduction Reaction:

• Reduction Reaction refers to a reaction in which either the addition of Hydrogen takes place or the removal of oxygen takes place.
• In the process of reduction, a chemical species also gains electrons.
• It is the reverse of the oxidation reaction.
• Eg - CO₂ gets reduced to form C₆H₁₂O₆ {addition of hydrogen}

Explanation:

• Plants prepare their food by the process called photosynthesis. 
• During photosynthesis, plants trap solar energy or light energy with the help of chloroplast present in the green leaves and convert it into Chemical energy
• A pigment called chlorophyll is present in the chloroplasts which are required in trapping sunlight
• Plants utilize Carbon dioxide and Water for the synthesis of carbohydrates during photosynthesis.
• The CO₂ gets reduced to form the carbohydrates while H₂O (Water) is oxidised and oxygen is liberated as a side product
• This gaseous exchange occurs through the stomata present on the leaf surface

These events can be demonstrated by the following equation:

\(\rm \underset{(Carbon\ dioxide)}{6CO_2} + \underset{(Water)}{6H_2 O} \xrightarrow[Chlorophyll]{Sunlight} \underset{(Carbohydrates)}{C_6H_{12}O_6} + \underset{(Oxygen)}{6O_2}\)

Correct Answer: T.W. Engelmann

Key Points

• T.W. Engelmann carried out the action spectrum experiment.
• Through this experiment, he deduced that the most photosynthetically active region will show the highest concentration of bacteria.

Additional Information

• Photosynthesis is the chemical process by which carbohydrates (organic molecules) are synthesized from inorganic materials like CO2 and H2O with the help of light energy which is trapped by pigments like chlorophyll.
• Oxygen is given out at the end of the photosynthesis process.

​

• Green plants, algae, and photosynthetic bacteria carry out the process of photosynthesis.
• Chlorophyll, carotenoids, and phycobilins are some of the most important pigments involved in the photosynthetic process.
• Chlorophyll pigments efficiently capture solar energy. 
• Chlorophylls absorb light in the violet, blue and red wavelengths of the light spectrum. This part of the light spectrum is also referred to as photosynthetically active radiation (PAR). It ranges from 400nm to 700nm.

Concept:

Oxidation reaction:

• Oxidation Reaction refers to a reaction in which either the addition of Oxygen takes place or the removal of Hydrogen takes place.
• It can also be said as the process of loss of one or more electrons by atoms or ions.
• Eg - H₂O gets oxidised to release O₂ {Removal of hydrogen}

Reduction Reaction:

• Reduction Reaction refers to a reaction in which either the addition of Hydrogen takes place or the removal of oxygen takes place.
• In the process of reduction, a chemical species also gains electrons.
• It is the reverse of the oxidation reaction.
• Eg - CO₂ gets reduced to form C₆H₁₂O₆ {addition of hydrogen}

Explanation:

• Plants prepare their food by the process called photosynthesis. 
• During photosynthesis, plants trap solar energy or light energy with the help of chloroplast present in the green leaves and convert it into Chemical energy
• A pigment called chlorophyll is present in the chloroplasts which are required in trapping sunlight
• Plants utilize Carbon dioxide and Water for the synthesis of carbohydrates during photosynthesis.
• The CO₂ gets reduced to form the carbohydrates while H₂O (Water) is oxidised and oxygen is liberated as a side product
• This gaseous exchange occurs through the stomata present on the leaf surface

These events can be demonstrated by the following equation:

\(\rm \underset{(Carbon\ dioxide)}{6CO_2} + \underset{(Water)}{6H_2 O} \xrightarrow[Chlorophyll]{Sunlight} \underset{(Carbohydrates)}{C_6H_{12}O_6} + \underset{(Oxygen)}{6O_2}\)

Correct answer is Priestly

Key Points

• The Bell Jar Experiment.
  • J. Priestley (1772) carried out very interesting experiment on Bell jar, rat, pudina or mint and candle. He came to conclude that plants purify air (burning of candles), and gaseous exchange occurs during photosynthesis.
    Priestley observed that a candle burning in a closed space – a bell jar, soon gets extinguished.
  • Similarly, a mouse would soon suffocate in a closed space. He concluded that a burning candle or an animal that breathe the air, both somehow, damage the air. But when he placed a mint plant in the same bell jar, he found that the mouse stayed alive and the candle continued to burn.
  • Priestley hypothesized as follows: Plants restore the air which breathing animals and burning candles remove.
     

The correct answer is Statement-A is incorrect but Statement-B is correct

Explanation:

• A part of a leaf is enclosed in a test tube containing some KOH soaked cotton (which absorbs CO₂), while the other half is exposed to air.
• The setup is then placed in light for some time.
• On testing for the presence of starch later in the two parts of the leaf, the exposed part of the leaf tested positive for starch while the portion that was in the tube, tested negative. This showed that CO₂ was required for photosynthesis.

The correct answer is 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂ 

Explanation:

• Photosynthesis is a fundamental biological process by which plants, algae, and some bacteria convert light energy into chemical energy, storing it in the bonds of glucose (a type of sugar)
• The overall chemical equation for photosynthesis in oxygen-evolving organisms is as follows 6CO₂ + 12 H₂O → C₆H₁₂O₆ + 6 H₂O + 6O₂ 

The correct answer is Green portion

Explanation:

• A variegated leaf or a leaf that was partially covered with black paper, and exposed to light.
• On testing these leaves for the presence of starch it was clear that photosynthesis occurred only in the green parts of the leaves in the presence of light.