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प्रश्न
What is the cell theory? Who propounded it and when?
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उत्तर
All animals and plants are composed of cells, which serve as the units of structure and function. This, in short, is called the Cell Theory,
Cell theory was propounded by Theodor Schwann and Matthias Schleiden in the year 1839 and was modified by Rudolf Virchow in 1858.
APPEARS IN
संबंधित प्रश्न
Carry out the following osmosis experiment:
Take four peeled potato halves and scoop each one out to make potato cups. One of these potato cups should be made from a boiled potato. Put each potato cup in a trough containing water. Now,
- Keep cup A empty.
- Put one teaspoon of sugar in cup B.
- Put one teaspoon salt in cup C.
- Put one teaspoon sugar in the boiled potato cup D.
Keep these for two hours. Then, observe the four potato cups and answer the following:
- Explain why water gathers in the hollowed portion of B and C.
- Why is potato A necessary for this experiment?
- Explain why water does not gather in the hollowed-out portions of A and D.
State the difference between eukaryotes and prokaryotes
The cell organelle that helps in the respiration of the cell is :
Name the part of the cell concerned with the following :
The entry of only certain substances into and out of the cell.
State whether the following statement is true (T) or False (F):
Genes are located on a chromosome.
Who coined the term “cell” ?
Match the name of the organelle given in Column A with its function given in Column B.
| Column A (Organelle) | Column B (Function) | ||
| 1 | leucoplast | a | help in cell division |
| 2 | nucleus | b | transport of material |
| 3 | ribosomes | c | making food |
| 4 | mitochondria | d | digesting foreign bodies |
| 5 | endoplasmic reticulum | e | storage of starch and proteins |
| 6 | golgi bodies | f | making the cell turgid |
| 7 | chloroplast | g | making proteins |
| 8 | centrosome | h | controlling all the vital activities of a cell |
| 9 | vacuole | i | releasing energy |
| 10 | lysosomes | j | synthesis of cell wall in a plant cell |
Justify the statement "cell is the basic unit of life"
What was the contribution of the following to our knowledge of cells?
Schleiden
What was the contribution of the following to our knowledge of cells?
Schwann
