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Assertion : Nucleus is the controlling c...

Assertion : Nucleus is the controlling centre of a cell.
Reason : Pores in the nuclear envelope regulate the flow of materials in and out of the nucleus.

A

If both assertion and reason are true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reason is false

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the assertion and the reason provided: ### Step 1: Analyze the Assertion The assertion states that "Nucleus is the controlling centre of a cell." - The nucleus is indeed known as the control center of the cell because it contains the genetic material (DNA) that dictates cellular functions and activities. It regulates gene expression and is responsible for cell growth, metabolism, and reproduction. Therefore, the assertion is **True**. ### Step 2: Analyze the Reason The reason states that "Pores in the nuclear envelope regulate the flow of materials in and out of the nucleus." - The nuclear envelope is a double membrane that surrounds the nucleus and contains nuclear pores. These pores are crucial for the transport of molecules such as RNA and proteins between the nucleus and the cytoplasm. Thus, the reason is also **True**. ### Step 3: Determine the Relationship Between Assertion and Reason Now we need to see if the reason correctly explains the assertion. - While both statements are true, the reason does not explain why the nucleus is the controlling center of the cell. The assertion is based on the presence of DNA and its role in controlling cellular activities, while the reason focuses on the function of nuclear pores. Therefore, the reason is not a correct explanation for the assertion. ### Conclusion - Assertion: True - Reason: True - The reason does not explain the assertion. Thus, the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation for the assertion. ### Final Answer: - Assertion: True - Reason: True - Explanation: The reason does not explain the assertion. ---
To solve the question, we need to analyze the assertion and the reason provided: ### Step 1: Analyze the Assertion The assertion states that "Nucleus is the controlling centre of a cell." - The nucleus is indeed known as the control center of the cell because it contains the genetic material (DNA) that dictates cellular functions and activities. It regulates gene expression and is responsible for cell growth, metabolism, and reproduction. Therefore, the assertion is **True**. ### Step 2: Analyze the Reason ...
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Assertion: Nucleus controls the metabolic activities of cytoplasm. Reason: Nucleus synthesizes enzymes and send them to cytoplasm to control the activities.

Why does a nuclear envelope have pores while other membranes of a cell do not?

Knowledge Check

  • The regulation of the flow of material into and outside the cell depends on:

    A
    cell membrane
    B
    mechanism of osmosis
    C
    chemical composition of plasma membrane
    D
    plasma membrane's permeability

  • Assertion: Extranuclear DNA occurs in the cytoplasmic matrix. Reason: It leaks out via nuclear pores into the cytoplasm.

    A
    If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion.
    B
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    C
    If Assertion is true but the Reason is false.
    D
    If both Assertion and Reasom are false.

  • Assertion: Each stoma is composed of two bean shaped cells known as guard cells. Reason: Guard cells regulate the opening and closing of stomata.

    A
    If both assertion and reason are true and reason is the correct explanantion of assertion
    B
    if both assertion and reason are true but reason is not the correct explanation of assertion.
    C
    if assertion is true but reason is false.
    D
    if both assertion and reason are false.

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    Read the statements below regarding the nucleus of a cell. Identify them as true or false and select the correct combination option. I. The nucleus displays an elaborate nucleoprotein fiber called chromatin during the interphase of the cell cycle. II. The space between the parallel membranes of the nuclear envelope is called the nucleoplasm. III. Nucleus was discovered first by Flemming. IV. The nuclear pores within the nuclear envelope are formed by the fusion of both membranes. {:("No.",I,II,III,IV),(1,"True","True","False","False"),(2,"True","False","False","False"),(3,"True","True","False","False"),(4,"True","False","False","True"):}

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