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.
APPEARS IN
RELATED QUESTIONS
Formalin, Iodine, DDT, Lime
Answer the following:
Give the overall chemical equation of photosynthesis in green plants.
Fill in the blank:
______ is the process which replenishes the atmospheric oxygen which the animal life consumes in respiration.
Complete the following by filling in the blanks numbered 1 to 10 with the appropriate word/term:
Photosynthesis involves light reaction and dark reaction. During light reaction, the chlorophyll present in the (1) ______ gets activated by absorbing light energy. This energy splits (2) ______ molecules to (3) ______ and oxygen and releases two electrons. This process is called (4) ______. The (5) ______ ions are picked up by NADP to form (6) ______. The ADP is converted to (7) ______. This process is called (8) ______. During the dark phase, the compound produced at the end of the light reaction reacts with carbon dioxide to form (9) ______. This product is converted to starch. The process is called (10) ______.
Complete the following sentence with appropriate word:
A plant that does not perform photosynthesis is _______.
Choose the correct option.
A cell that lacks chloroplast does not ______.
During photosynthesis, ________ is produced and stored in the leaf.
Photosynthesis converts energy X into energy Y.
- What are X and Y?
- Green plants are autotrophic in their mode of nutrition. Why?
Assertion (A): All food chains begin with herbivores.
Reason (R): Green plants are heterotrophs.
