CELL STRUCTURES AND FUNCTION
CELL ORGANELLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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all cells have a cell wall
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all cells arise from pre-existing cells
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all cells are capable of photosynthesis
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all cells can develop into any other type of cell
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Detailed explanation-1: -In 1838 Schleiden defined the cell as the basic unit of plant structure, and a year later Schwann defined the cell as the basic unit of animal structure. Schleiden and Schwann articulated their observations as a unified theory-the cell theory-in 1839.
Detailed explanation-2: -In 1838, Matthias Schleiden, a German botanist, concluded that all plant tissues are composed of cells and that an embryonic plant arose from a single cell. He declared that the cell is the basic building block of all plant matter.
Detailed explanation-3: -published from Berlin Mikroskopische Untersuchungen, in which he demonstrated that Schleiden’s conclusion also applies to animals, thus establishing the cell as the elementary unit common to both plant and animal kingdoms.
Detailed explanation-4: -Schleiden and Schwann, who are usually given credit for elucidating the cell theory, made their marks in 1838 and 1839. In 1838 Matthais Schleiden (1804–1881) proposed that every structural element of plants is composed of cells or the products of cells.