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Go through the following facts - I. The...

Go through the following facts -
I. The pressure that is produced by swelling of wood had been used by prehistoric man to split rocks and boulders
II. The seedling is able to come out of soil due to development of a pressure. This pressure is -

A

O.P.

B

T. P.

C

I.P.

D

`Psi_w`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the two facts presented, we will analyze each statement step by step. ### Step-by-Step Solution: 1. **Understanding the First Fact**: - The first fact states that the pressure produced by the swelling of wood was used by prehistoric man to split rocks and boulders. - This is true because dry wood, when it absorbs water, swells and exerts pressure. This pressure can be strong enough to split rocks apart. **Hint**: Think about how materials change when they absorb water and the physical forces that result from that change. 2. **Understanding the Second Fact**: - The second fact indicates that seedlings are able to emerge from the soil due to the development of a pressure. - This pressure is specifically due to the process of imbibition, where seeds absorb water and swell. The swelling generates internal pressure that can break the seed coat, allowing the seedling to emerge. **Hint**: Consider the role of water absorption in seed germination and how it affects the seed structure. 3. **Identifying the Type of Pressure**: - The pressure that helps the seedling to break through the soil is known as **imbibition pressure (Ip)**. This pressure arises from the absorption of water by the seed, leading to an increase in volume and internal pressure. **Hint**: Remember the term "imbibition" and how it relates to the absorption of water in seeds. 4. **Conclusion**: - Both statements are correct. The first statement illustrates a historical use of wood swelling, and the second statement explains the biological process that allows seedlings to emerge from the soil, which is due to imbibition pressure. **Hint**: Reflect on how both facts relate to the physical properties of materials and biological processes. ### Final Answer: - The pressure that allows seedlings to emerge from the soil is called **imbibition pressure (Ip)**, which is generated by the absorption of water by the seed.
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