Tag: experiments on photosynthesis - gases

Questions Related to experiments on photosynthesis - gases

Multiple choice botany how plants grow experiments on photosynthesis - light importance of light for photosynthesis photosynthesis necessities- experiments various experiments on photosynthesis experiments on photosynthesis - gases

Match List-I with List-II and select the correct answer.

List-I List-II
a. Richnmond lang effect $1$. Reversal of red-drop
b. Emerson effect $2$. Inhabitation of glycolysis by oxygen
c. Pasteur effect $3$. Inhibition of photosynthesis by oxygen
d. Warburg effect $4$. Senscescence retardation in detached leaves
  1. A-$1$, B-$4$, C-$2$, D-$3$
  2. A-$4$, B-$1$, C-$3$, D-$2$
  3. A-$1$, B-$4$, C-$3$, D-$2$
  4. A-$4$, B-$1$, C-$2$, D-$3$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Richmond-Lang effect refers to senescence retardation in leaves by cytokinins (4). Emerson effect is the enhancement of photosynthesis (reversal of red-drop) (1). Pasteur effect is the inhibition of glycolysis by oxygen (2). Warburg effect is the inhibition of photosynthesis by high oxygen concentration (3).

Multiple choice botany how plants grow experiments on photosynthesis - light importance of light for photosynthesis photosynthesis necessities- experiments various experiments on photosynthesis experiments on photosynthesis - gases

The upper dormant seeds of cocklebur(Xanthium) germinate only under high oxygen levels. The oxygen is required for _______________.

  1. Degradation of inhibitors

  2. Synthesis of promoters

  3. Respiration

  4. Photorespiration

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

In many dormant seeds, oxygen is required for the aerobic respiration process that provides the energy and metabolic intermediates necessary to degrade growth inhibitors (like ABA) that maintain dormancy.

Multiple choice botany how plants grow experiments on photosynthesis - light importance of light for photosynthesis photosynthesis necessities- experiments various experiments on photosynthesis experiments on photosynthesis - gases
Ingenhousz in an experiment showed that in bright sunlight, small bubbles were formed around the green parts of the plant, while in the dark, they did not. He identified these bubbles to be of ____________.
  1. $CO _{2}$
  2. $H _{2} O $
  3. $O _{2} $
  4. $H _{2} $
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Jan Ingenhousz (1730-1799), in his experiment with an aquatic plant, showed that in bright sunlight, small bubbles were formed around the green parts while in the dark, no such bubbles formed. He found out these bubbles to be of oxygen. He thus, confirmed that purification of air or formation of dephlogiston is carried out by green plants only in presence of sunlight. 

Multiple choice botany how plants grow experiments on photosynthesis - light importance of light for photosynthesis photosynthesis necessities- experiments various experiments on photosynthesis experiments on photosynthesis - gases

A beaker is filled with water and twigs of Hydrilla are inserted in the funnel so that the cut ends are in the tube of the funnel and the funnel is put in the water. Then a test tube full of water is inverted over the inverted funnel. Air bubbles from the plant collect at the tip of the tube. This experiment demonstrates that oxygen is evolved during photosynthesis. But, if boiled water is used instead of pond water in which Hydrilla grows, then?

  1. Air bubbles are not produced

  2. Air bubbles are produced in large numbers

  3. Only a few air bubbles are produced

  4. Only one air bubble is produced

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

If boiled water is used in the test tube, there will be no air bubbles. This is hydrilla cannot survive the high temperature of boiled water. 

So, option A is the correct answer.

Multiple choice biology nutrition and respiration importance of light for photosynthesis various experiments on photosynthesis experiments on photosynthesis - gases

Before setting up an experiment to show that seeds release $CO _{2}$ during respiration, the
seeds should be :

  1. dried completely.

  2. boiled to make them soft.

  3. soaked in vinegar.

  4. kept moist till they germinate.

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

To demonstrate respiration, seeds must be alive and metabolically active. Germinating seeds are actively respiring and consume oxygen while releasing carbon dioxide.

Multiple choice biology nutrition and respiration importance of light for photosynthesis various experiments on photosynthesis experiments on photosynthesis - gases

Four sets of three precautions to be taken while setting up the experiment to show that $CO _{2}$ is evolved during respiration are given below. Find the correct set of precautions.

  1. Airtight setup, delivery tube dips in water in beaker, germinating seeds in flask

  2. Thread holding KOH pellets, airtight flask, delivery tube just above the water level in the beaker

  3. Germinated seeds completely under the water in the flask, experimental setup not airtight, delivery tube above water level.

  4. Delivery tube touching the bottom of the beaker, KOH pellets kept along with germinating seeds at the bottom of the flask, seeds should not germinate.

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

The experiment requires an airtight setup to prevent atmospheric CO2 from interfering. KOH pellets are used to absorb the CO2 produced by the germinating seeds, creating a partial vacuum that draws water up the delivery tube.

Multiple choice biology nutrition and respiration importance of light for photosynthesis various experiments on photosynthesis experiments on photosynthesis - gases

A student sets up the apparatus for the experiment to show that $CO _{2}$ is released during
respiration. After two hours he would observe :

  1. KOH turning milky

  2. water level rising in the bent tube in the beaker.

  3. water level decreasing in the bent tube

  4. no change in water level in the bent tube.

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

As the germinating seeds respire, they consume oxygen. The KOH pellets absorb the CO2 released. This consumption of gas inside the airtight flask creates a pressure drop, causing the water level in the bent tube to rise.

Multiple choice biology nutrition and respiration importance of light for photosynthesis various experiments on photosynthesis experiments on photosynthesis - gases

What happens if the process of photosynthesis in plants for the formation of carbohydrate ?

  1. Reduction of $O _2$
  2. Reduction of $N _2$
  3. Reduction of $CO _2$
  4. Oxidation of $H _@$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Formation of glucose by the unitlization of 6 molecules of carbon dioxide and 12 molecules of water in presence of sunlight in chloroplast is called Photosynthesis. In this process Water is oxidized (loses electrons) in  and carbon dioxide is reduced(gains electrons).
So, the correct option is 'Reduction of CO2'.