Advertisements
Advertisements
Question
The figure given below is for performing an experiment on photosynthesis.
Answer the following:
(i) What is the aim of this experiment?
(ii) Describe an experiment to show that light is necessary for photosynthesis.
(iii) What do you conclude from this experiment?
(iv) What is the role of light in photosynthesis?
Advertisements
Solution
- To demonstrate that sunlight is necessary for photosynthesis.
- Take a potted plant and keep it for 2-3 days in dark to destarch its leaves. Take one leaf and cover it on both sides with two black paper strips, as shown in the diagram, with the help of cellophane tape. Now keep the potted plant in light. After a few hours pluck the leaf and remove the black strips. Boil the leaf in alcohol and wash it in water. Test the leaf for starch with iodine solution. The leaf turns blue all over except the region covered with black stripes. This shows that the region which did not receive light could not synthesise starch. Thus, light is necessary for photosynthesis.
- Light is necessary for photosynthesis.
- Light supplies energy in the form of photons to split water during tight reaction.
RELATED QUESTIONS
The diagrams given below represent the relationship between a mouse and a physiological process that occurs in green plants. Study the diagrams and answer the questions that follow:
- Name the physiological process occurring in the green plant that has kept the mouse alive.
- Explain the physiological process mentioned above.
- Why did the mouse die in bell jar B?
- What is the significance of the process as stated in (i) for life on earth?
- Represent the above mentioned physiological process in the form of a chemical equation.
The diagram given below represents an experiment to prove the importance of a factor in photosynthesis. Answer the questions that follow :
Explain the process of Photosynthesis.
State the main functions of the following:
Cytokinins
Define the following:
Plant pigments
A plant is kept in a dark cupboard for 48 hours before conducting any experiment on photosynthesis in order to
Complete the following food chain by writing the names of appropriate organisms in the blanks:
→ __________ → __________ → Hen → Man
Give technical term:
Organisms which cannot prepare their own food by photosynthesis.
Choose the correct option.
The net result of photo-oxidation of water is release of ______.
______ is positively hydrotropic as well as positively geotropic.
