Given below are two statements
Statement I: Matthias Schleiden and Theodor Schwann proposed the first two components of the ‘cell theory’.
Statement II: Rudolf Virchow proposed the third component of the ‘cell theory’.
In light of the above statements, choose the most appropriate answer from the options given below
Statement I: Matthias Schleiden and Theodor Schwann proposed the first two components of the ‘cell theory’.
Statement II: Rudolf Virchow proposed the third component of the ‘cell theory’.
In light of the above statements, choose the most appropriate answer from the options given below
Show Hint
Virchow (Physician) = "Cells come from cells."
Remember the years: 1838-1839 for the start and 1855 for the completion of the theory.
- Both Statement I and Statement II are correct
- Both Statement I and Statement II are incorrect
- Statement I is correct but Statement II is incorrect
- Statement I is incorrect but Statement II is correct
The Correct Option is A
Solution and Explanation
The question refers to the historical development of the Cell Theory, one of the unifying principles of biology. It asks to confirm the contributions of three key scientists: Schleiden, Schwann, and Virchow.
Step 2: Detailed Explanation:
• Analysis of Statement I:
In 1838, Matthias Schleiden, a German botanist, concluded that all plant tissues are composed of cells.
In 1839, Theodor Schwann, a German zoologist, concluded that all animal tissues are composed of cells and stated that the cell is the basic unit of structure in organisms.
Together, they formulated the initial Cell Theory:
1. All living organisms are composed of one or more cells.
2. The cell is the basic unit of structure and organization in organisms.
This confirms Statement I is correct.
• Analysis of Statement II:
Schleiden and Schwann's theory did not explain how cells are formed (they incorrectly believed in spontaneous "crystallization").
In 1855, Rudolf Virchow added the third tenet: "Omnis cellula e cellula," which means "All cells arise from pre-existing cells."
This completed the classical cell theory. Thus, Statement II is correct.
Final Answer:
Both Statement I and Statement II are historically and scientifically accurate.
Therefore, the correct choice is option (A).
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Choose the correct answer from the options given below:
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