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प्रश्न
Two groups (A & B) of bean plants of similar size and same leaf area were placed in identical conditions. Group A was exposed to the light of wavelength 400-450 nm & Group B to light of wavelength of 500-550 nm. Compare the photosynthetic rate of the 2 groups giving reasons.
उत्तर
‘A’ group of plants exposed to light of 400 - 450nm. Chlorophyll a shows maximum absorption peak at 450nm (blue region). Hence rate of photosynthesis was high.
‘B’ group of plants exposed to light of 500 - 550nm. This wavelength refers to green region of the spectrum. Chlorophyll does not absorb light in the green region but reflects green. So plants appear green rate of photosynthesis was negligible in these plants.
संबंधित प्रश्न
Look at leaves of the same plant on the shady side and compare it with the leaves on the sunny side. Or, compare the potted plants kept in the sunlight with those in the shade. Which of them has leaves that are darker green? Why?
Short answer question.
Why do leaves generally look green?
Short answer question.
Which four of the following are needed for photosynthesis in a leaf:
(i) Carbon dioxide:
(ii) Oxygen:
(iii) Nitrates :
(iv) Water:
(v) Chlorophyll:
(vi) Soil:
(vii) Light:
Short answer question.
Which gas is taken in and which one is given out by the leaf in bright sunlight?
(i) Taken in :
(ii) Given out:
State whether the following statement is True or False:
Green plants prepare their food by using two raw materials, oxygen and water.
Long answer question.
What is the role of chlorophyll in photosynthesis?
Answer the following in one word.
Which organ is called the voice box?
Tick the most appropriate answer.
Plants have these for the exchange of gases.
Attempt any TWO of the following:
Describe ‘any two’ factors affecting the rate of photosynthesis.
Identify the false statement and rewrite it correctly by changing the first or last word only.
Photosynthesis stops at a temperature of about 35°C.
Are the following statement true or false? Give a reason in support of your answer.
The outside atmospheric temperature has no effect on the rate of photosynthesis.
Photorespiration is favoured by :
Photosynthetic organisms occur at different depths in the ocean. Do they receive qualitatively and quantitatively the same light? How do they adapt to carry out photosynthesis under these conditions?
Why does the rate of photosynthesis decrease at higher temperatures?
The figure shows the effect of light on the rate of photosynthesis. Based on the graph, answer the following question:
- At which point/s (A, B or C) in the curve is light a limiting factor?
- What could be the limiting factor/s in Region A?
- What do C and D represent on the curve?
Graph of light intensity on the rate of photosynthesis
