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A; Homogeniser and ultracentriguge are t...

A; Homogeniser and ultracentriguge are the devices for separating various cell organelles.
R; The radioactive substances used in biological studies are called Tracer elements.

A

If both As and R are correct and R is correct explanation of As

B

If both As and R are correct but R is not correct explanation of As

C

If As is correct, R is wrong

D

If both As and R are wrong.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reason question, we will break it down into steps: ### Step 1: Analyze the Assertion The assertion states: "Homogeniser and ultracentrifuge are the devices for separating various cell organelles." - **Explanation**: This statement is true. A homogenizer is used to break down cells and release their organelles into a solution, while an ultracentrifuge separates these organelles based on their density. ### Step 2: Analyze the Reason The reason states: "The radioactive substances used in biological studies are called Tracer elements." - **Explanation**: This statement is also true. Tracer elements are indeed radioactive substances that are used in biological studies to track the movement and distribution of molecules within biological systems. ### Step 3: Determine the Relationship Between Assertion and Reason - While both statements are true, the reason does not explain the assertion. The assertion is about the separation of cell organelles, while the reason discusses the use of tracer elements in biological studies. ### Step 4: Conclusion - Since both the assertion and the reason are true, but the reason does not correctly explain the assertion, the correct answer is that both A and R are true, but R is not the correct explanation of A. ### Final Answer - The correct option is: Both A and R are true, but R is not the correct explanation of A. ---
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DINESH PUBLICATION ENGLISH-ENVIRONMENTAL ISSUES-Assertion and reason
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  11. Assertion: Life on earth originated by interaction of the various chem...

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  13. $ solar system has 15 planets. ! Earth is the major member of the so...

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  14. $ The approximate distance between the sun and the Earth is about 148....

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