Tag: photosynthesis and respiration

Quizzes (6) Questions (14)

Questions Related to photosynthesis and respiration

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

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

  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
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Photosynthesis relies on the absorption of visible light by chlorophyll pigments. UV and X-ray radiations have much higher energy levels than visible light and are not effectively absorbed by chlorophyll to drive the photochemical reactions, often causing damage to biological molecules instead.

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

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?

  1. Arnon

  2. Emerson

  3. Warburg

  4. Ruben
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

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

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.

  1. Sunlight

  2. Iodine

  3. Starch

  4. Darkness
Reveal answer Fill a bubble to check yourself
A Correct answer
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.