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प्रश्न
How does a gap junction facilitate intercellular communication?
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उत्तर
A gap junction facilitates intercellular communication by allowing the small signalling molecules to pass from cell to cell. These are hydrophilic junctions that are made up of two protein cylinders called connexus. The movement of molecules through this channel is controlled by PH and Ca2+ions Concentration.
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संबंधित प्रश्न
Based on the following information, identify the three types of epithelial tissue in the figures given below :
| a |  |
b |  |
c |  |
(1) Cuboidal epithelium: It consists of a single layer of cuboidal cells.
(2) Columnar epithelium: It is composed of tall, cylindrical cells with oval nuclei usually placed at the base of the cells.
(3) Ciliated epithelium: It consists of cells being hair-like cilia on their free surface.
Write the name of the following tissue.
Tissue lining the inner surface of the mouth.
Answer the following question.
Describe different types of cell junctions.
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The main function of the cuboidal epithelium is
The ciliated epithelium lines the______.
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The lining of blood vessels, lung alveoli and kidney tubules are all made up of epithelial tissue.
Write true (T) or false (F)
Epithelial layer is permeable layer.
Differentiate between sclerenchyma and parenchyma tissues. Draw well labelled diagram.
Give reasons for
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The ______ epithelium is also known as the pavement membrane.
______ epithelium is seen in sweat glands.
Write one point of difference between
Simple and compound epithelial tissue.
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Name the different cell junctions found in tissues.
The body of sponges does not possess tissue level of organisation though it is made of thousands of cells. Comment.
Classify and describe epithelial tissue on the basis of structural modifications of cells.
