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

Word dark reaction for biosynthetic phase of photosynthesis is misnomer word because ___________________.

  1. Dark reaction occur during dark

  2. Dark reaction occur during day

  3. Dark reaction is completely free from light

  4. Dark reaction occur during short dark intervals
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The term dark reaction for the biosynthetic phase of photosynthesis is a misnomer because these reactions do not actually require darkness or occur exclusively at night. Instead, they can and do occur during the day, relying on the ATP and NADPH produced during the light-dependent reactions.

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

A green plant bends towards the source of light when exposed to the light on only one side, it bends towards the source of light as it grows. Which of the following is the best explanation of the phenomenon 

  1. The apices of their stems are attracted by light

  2. They need light for photosynthesis

  3. Some auxins accumulates on the shaded side to induce greater cell elongation on that side

  4. Light stimulates the cells on the illuminated side to increase in length
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Accumulation of auxin as the apex of the plant, which is responsible for the phototropism movement so that plant cells are elongated.

So the correct option is C.

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

Two green plants are kept separately in oxygen free containers, one in the dark and the other in continuous light. Which one will live longer? 

  1. The plant kept in dark

  2. The plant kept in light

  3. Both the plants will live for the same time

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The plant kept in continuous light will live longer, because it will be able to produce oxygen required for its respiration by the process of photosynthesis.

Oxygen is evolved as a by-product of photosynthesis during photolysis of water.
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

(i) Pluck the leaf to be experimented
(ii) Cover a portion of leaf on both sides by using strips of black paper
(iii) Keep the plant in dark place for three days to destarch its leaves.
(iv) Test the experimental leaf the the presence of starch 
(v) Expose the plant to sunlight for four hours 
(vi) Remove the black paper strip from the leaf

Given in the box are steps written randomly for the experiment to show that light is essential for photosynthesis. Which of the following sequences of steps is to be followed by the successful run of the experiment?

  1. (i), (iii), (ii) (iv), (v), (vi)

  2. (ii), (i), (v), (vi), (iii), (iv)

  3. (iii), (ii), (v), (i), (vi), (iv)

  4. (v), (ii), (i), (iii), (iv), (vi)
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The starch in the leaves is eliminated by keeping the plant in a dark place for 3 days. A leaf is selected and covered with a black strip on both sides. The plant is kept in sunlight for 4 hours. The experimental leaf is plucked and the strip is removed from it to perform the starch test. It is found that he leaf covered with black paper will turn brown and the part of the exposed leaf will turn blue-black. This result proves that starch is formed in the leaf where sunlight is available and is not formed in absence sunlight. Thus the correct answer is option  C.

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.

Multiple choice biology mineral nutrition in plants hydroponics hydroculture essential and non-essential mineral elements

In aeroponics, which one of the following absorbs required nutrients to the plant?

  1. Roots

  2. Stem

  3. Leaves

  4. External factors
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Aeroponics is the process of growing plants in an air or mist environment without the use of soil or an aggregate medium. In aeroponics, growing plants are suspended in a closed or semi-closed environment by spraying the plant's roots with an atomized or sprayed, nutrient-rich water solution. 
So the correct option is "roots". 
Multiple choice biology mineral nutrition in plants hydroponics hydroculture essential and non-essential mineral elements

Which of the following technique/s of agriculture is gaining significance in developing space foods?

  1. Aeroponics

  2. Hydroponics

  3. Somatic hybridization

  4. Both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

 A.Aeroponics is growing a plant in air or mist environment.This technique is gaining significance in developing space foods because it do not require soil to grow the plant.

 B.hydroponic is growing plant in nutrient-enriched water without soil. This technique is gaining significance in developing space foods because it do not require soil to grow the plant.
C.Somatic hybridization - Fusion of protoplasts of two different plants.
So the correct option is "both A and B".