Life Processes in Plants Class 7 - Chapter 10 Curiosity

Q 1
Question
Complete the following table
S.No.
Feature
Photosynthesis
Respiration
1.
Raw materials
2.
Products
3.
Word equation
4.
Importance
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Q 2
Question
Imagine a situation where all the organisms that carry out photosynthesis on the earth have disappeared. What would be the impact of this on living organisms?
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Q 3
Question
A potato slice shows the presence of starch with iodine solution. Where does the starch in potatoes come from? Where is the food synthesised in the plant, and how does it reach the potato?
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Q 4
Question
Does the broad and flat structure of leaves make plants more efficient for photosynthesis? Justify your answer.
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Q 5
Question
X is broken down using Y to release carbon dioxide, Z, and energy.
X + Y → Carbon dioxide + Z + Energy
X, Y, and Z are three different components of the process. What do X, Y, and Z stand for?
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Q 6
Question
Krishna set-up an experiment with two potted plants of same size and placed one of them in sunlight and the other in a dark room, as shown in Fig. 10.10. Answer the following questions —
(i) What idea might she be testing through this experiment?
(ii) What are the visible differences in plants in both the conditions?
(iii) According to you, leaves of which plants confirm the iodine test for the presence of starch?
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Q 7
Question
Vani believes that 'carbon dioxide is essential for photosynthesis'. She puts an experimental set-up, as shown in Fig. 10.11, to collect evidence to support or reject her idea. Answer the following questions —
(i) In which plant(s) in the above set-up(s) will starch be formed?
(ii) In which plant(s) in the above set-up(s) will starch not be formed?
(iii) In which plant(s) in the above set-up(s) will oxygen be generated?
(iv) In which plant(s) in the above set-up(s) will oxygen not be generated?
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Q 8
Question
Ananya took four test tubes and filled three-fourth of each test tube with water. She labelled them A, B, C, and D (Fig. 10.12). In test tube A, she kept a snail; in test tube B, she kept a water plant; in test tube C, she kept both a snail and a plant. In test tube D, she kept only water. Ananya added a carbon dioxide indicator to all the test tubes. She recorded the initial colour of water and observed if there are any colour changes in the test tubes after 2–3 hours. What do you think she wants to find out? How will she know if she is correct?
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Q 9
Question
Design an experiment to observe if water transportation in plants is quicker in warm or cold conditions.
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Q 10
Question
Photosynthesis and respiration are essential to maintain balance in nature. Discuss.
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Project 1
Project
Develop a bottle garden by planting a growing plant like spider plant or jade plant in a large transparent bottle. After growing the plant properly for some time, seal the mouth of the bottle. Observe the growth of the plant. If the plant grows well, it is maintaining the exchange of gases — the carbon dioxide from respiration is used for photosynthesis, and the oxygen from photosynthesis is used in respiration.
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Key Points
A sealed bottle garden keeps growing because its gases are recycled inside.
Key Points
Plant a spider or jade plant in a large clear bottle.
Let it grow well, then seal the bottle's mouth.
The plant respires and gives out carbon dioxide.
It uses that carbon dioxide for photosynthesis in light.
The oxygen it makes is used again in respiration.
So the same gases keep cycling and the plant survives.
A bottle garden shows photosynthesis and respiration balancing each other.

Project 2
Project
How are plant processes like photosynthesis, respiration, and water and food transportation crucial for crop production? Find out how each process helps a crop grow, and what happens to the crop if any one of these processes is missing or slowed down.
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Key Points
All these processes work together to help crops grow and give good yield.
Key Points
Photosynthesis makes the food that the crop needs.
Respiration releases energy for growth from that food.
The xylem brings water and minerals to all parts.
The phloem carries food to grains, fruits, and roots.
If any process slows, the crop grows poorly.
Healthy crops need food-making, energy, and transport all working well.

Project 3
Project
Visit a greenhouse, if there is one near your place. Observe how people grow plants in a greenhouse. Find out how they regulate the amount of light, water, and carbon dioxide used to grow plants.
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Key Points
A greenhouse controls light, water, and air to help plants grow better.
Key Points
A greenhouse is a covered space for growing plants.
Growers control how much light the plants get.
They give the right amount of water regularly.
They may also manage the carbon dioxide in the air.
These controls help plants do more photosynthesis.
By controlling light, water, and air, greenhouses help plants grow well.
🔬 Know a Scientist
Kamala Sohonie (1911–1998) was a woman scientist of India.
She earned a Ph.D. for her work on respiration in plants.
She worked to improve the nutritive value of plant foods.
She also worked on a coconut palm drink called Neera.