Advertisements
Advertisements
Question
Describe fully one experiment with potted green plant to show that starch is not produced in the leaves when carbon dioxide is not available (diagrams essential)
Solution
Experiment to show that starch is not produced in the leaves when carbon dioxide is not available:
a. A potted plant is kept in the dark for two days to destarch the leaves.
b. Take a wide mouth bottle and fill 1/ 3'd of it with caustic potash solution.
c. Insert half part of the leaf of potted plant in the bottle and do not let the leaf to
touch the solution in the bottle.
d. The apparatus is kept in sunlight for few hours.
e. The leaf is plucked and tested for starch.
f. Only the portion of the leaf which is outside the bottle turns blue and the part of
the leaf inside the bottle remains colourless because it did not get C0 2 for
photosynthesis. All the C02 present in the bottle was absorbed by caustic
solution.
APPEARS IN
RELATED QUESTIONS
An experiment was set up as shown in the figure given below . The twig in the diagram was intact on the plant and it was as such in sunlight for a few hours .
(i) What is the aim of the above experiment ?
(ii) Why was potassium hydroxide placed inside the conical flask ?
(iii) What test would you perform on the leaf inside the flask?
(iv) What is the expected result of the above test ?
(v) Is it necessary to similarly test on outer leaf also ? Giva a reason .
Are the following statement true or false? Give a reason in support of your answer.
Destarching of the leaves of a potted plant can occur only at night.
Photosynthesis in green plants is directly and indirectly dependent on so many plant structures.
Explain briefly the role of the following structures in this process is Xylem tissue in the leaf veins
Given below is the representation of a certain phenomenon in nature. With four organisms 1-4.
- Name the phenomenon represented.
- Name any one organism that could be shown at No. 5.
- Name the biological process which was the starting point of the whole chain.
- Name one natural element which all the organisms 2-4 and even 5 are getting from No. 1 for their survival.
A potted plant was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours. One of the leaves was covered with black paper in the centre. The potted plant was then placed in sunlight for a few hours.
Write a balanced chemical equation to represent the process of photosynthesis.
The diagram below shows two test-tubes A and B. Test-tube A contains a green water plant. Test-tube B contains both a green water plant and a snail. Both test-tubes are kept in sunlight. Answer the questions that follow:
(a) Name the physiological process that releases the bubbles of oxygen.
(b) Explain the physiological process as mentioned above in (a).
(c) What is the purpose of keeping a snail in test-tube B?
(d) Why does test-tube B have more bubbles of oxygen?
(e) Give an example of a water plant that can be used in the above experiment.
(f) Write the overall chemical equation for the above process.
Differentiate Between:
Light reaction and Dark reaction.
Choose the Odd One Out
