Tag: photosynthesis and respiration

Questions Related to photosynthesis and respiration

UV or X-ray radiation is NOT suitable for photosynthesis is green plants because such a radiation.

biology photosynthesis and respiration experiments on photosynthesis - light importance of light for photosynthesis photosynthesis necessities- experiments

  1. Is not visible

  2. Is not absorbed by chlorophyll

  3. Causes ionization of chlorophyll

  4. Leads to an increase in rotational and vibration energy of chlorophyll

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Correct Option: A

Who observed that when chlorella cells are exposed to continuous light, the rate of  photosynthesis was less as compared to those exposed in intermittent light?

biology photosynthesis and respiration experiments on photosynthesis - light importance of light for photosynthesis photosynthesis necessities- experiments

  1. Arnon

  2. Emerson

  3. Warburg

  4. Ruben

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Correct Option: B
Explanation:

  • Warburg discovered that a decrease in photosynthesis by increasing the oxygen concentration. Oxygen is the competitive inhibitor of the carbon dioxide fixation by RuBisCo, which initiates photosynthesis. Furthermore, oxygen stimulates photorespiration which reduces photosynthetic output. These two mechanisms working together are responsible for the Warburg effect. So, this option is incorrect.
  • Arnon discovered the photosynthetic phosphorylation. So, this option is incorrect.
  • Samuel Ruben discovered that oxygen, which is released during photosynthesis came from a water molecule. So, this option is incorrect.
  • Emerson observed that when Chlorella cells are exposed to continuous light, the rate of photosynthesis was less as compared to those exposed to the intermittent light. 

So, the correct answer is option B.

What screens out 99% of harmful rays of sunlight?

biology photosynthesis and respiration experiments on photosynthesis - light importance of light for photosynthesis photosynthesis necessities- experiments

  1. $CO$

  2. $CO _{2}$

  3. $O _{3}$

  4. $O _{2}$

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Correct Option: C

A plant was kept in a dark room for a week. When its leaves are tested with iodine solution, it did not show the presence of starch. From this experiment we can conclude that _____ is required for photosynthesis.

biology photosynthesis and respiration experiments on photosynthesis - light importance of light for photosynthesis photosynthesis necessities- experiments

  1. Sunlight

  2. Iodine

  3. Starch

  4. Darkness

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Correct Option: A
Explanation:

Sunlight is essential for photosynthesis as the plant is kept in dark room for a week there is a lack of sunlight hence photosynthesis has not taken place.