Tag: cell as structural and functional unit
Questions Related to cell as structural and functional unit
Choose the correct statement with respect to cell theory
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All organisms are made up of one or more cells.
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All organisms must be able to reproduce.
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Cells have organelles to carry on their functions.
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Cells evolved from a primordial soup on early earth.
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Cells are able to regulate their external environment.
- The generally accepted parts of the cell theory include: All known living things are made up of one or more cells.
- All living cells arise from pre-existing cells by the division and cell is the basic unit of life.
Cells were found to develop from pre-existing cells by
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Lamarck
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Schleiden and Schwann
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Virchow
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Leeuwenhoek
Who initiated cell concept?
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Robert Hooke
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Leeuwenhoek
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Grew
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Schleiden and Sohwann
Nehmiah Grew initiate cell concept when he found that plant tissues contain minute elementary structures or cells. Thus, it was a 'basic generalization' extended to all the plants by Schleiden. Schleiden by himself neither discovered cell nor described their structure but extended the cell concept to all plants.
"Omnis cellula e cellula" is a generalization, given by
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Lamarck.
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Dutrochet.
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Leeuwenhoek.
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Virchow.
Rudolf Virchow explained that cells divided and new cells are formed from pre-existing cells. "Omnis cellula e cellula" is also attributed to the Cell Theory, that works on a similar principle. The cell theory asserts that every organism is formed of the same units of the organisation, known as cells.
An individual has a number of different type of cells was first stated by ______________.
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Dujardin.
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Robert Brown.
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Dutrochet.
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Schleiden and Schwann.
Leeuwenhoek was the first to see 'free-living cells' under his microscope. In 1809, Lamarck concluded that all living beings are formed of cells. Living substance was first observed by Corti in 1772 and was named sarcode by Dujardin in 1835. Dutrochet believed in the individuality of cells, i.e., living organisms are made up of a number of individual cells. The nucleus was discovered by Robert Brown and Schleiden and Schwann are credited with the formulation of the cell theory.
Cell theory was propounded by
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A botonist.
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A zoologist.
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Both a botanist and a zoologist.
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A psychlologist.
New cells generate from
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Bacterial fermentation.
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Regeneration of old cells.
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Pre-existing cells.
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Abiotic material.
New cells generate from :
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Bacterial fermentation
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Regeneration of old cells
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Pre-existing cells
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Abiotic materials
New cells generate from pre-existing cells. Rudolf Virchow (1985) first explained that cells divide and new cells are formed from pre-existing cells (omnis cellula-e cellula). He modified the hypothesis of Schleiden and Schwann to give cell theory a final shape.
Cell theory now is understood as:
- All living organisms are composed of cells and the product of cells.
- All cells arise from pre-existing cells.
Choose the correct answer from the alternatives given.
Which is not true about the cell theory?
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It states that all organisms are composed of cells
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It states that all cells come from pre-existing cells
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It states that bacteria and other small organisms can arise spontaneously
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It is accepted today by biologists as applying to virtually all forms of life
According to the cell theory all organisms (unicellular or multicellular) are formed of cells. It also states that all cells arise from pre-existing cells by cell division and do not originate spontaneously. Bacteria and other organisms therefore cannot arise spontaneously. So, the correct answer is 'It states that bacteria and other small organisms can arise spontaneously'.
State the following statements are true or false.
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True
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False
- Reproduction is based on the phenomenon that new cells arise from preexisting cells.
- Spontaneous generation is not possible.