Tag: kinds of plant tissue
Questions Related to kinds of plant tissue
Which of the following sclereids are the characteristic of intercellular spaces of Nymphaea?
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Osteosclereids
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Brachysclereids
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Macrosclereids
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Astrosclerieds
Astrosclerieds is a sclereid having its cell wall drawn out into lobes or arms to form a more or less stellate body. It is found in certain xerophytes. Nymphaea contains large intercellular spaces, which occur in the petiole. These airspaces are surrounded by long columns of parenchyma cells. The columnar cells contain chloroplasts and are presumably photosynthetic. Part of a large astroscleried can be seen cutting across one of the parenchymatous fingers. These sclereids add some mechanical strength to fragile structure.
In grasses, certain adaxial epidermal cells along the veins modify themselves into large empty, colourless cells, called as
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Bulliform cells
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Companion cells
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Guard cells
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Subsidiary cells
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Albuminous cells
Bulliform cells are so called because of its peculiar bubble shape. It mainly occurs on the upper surface of the leaves present in grasses. Water present in these cells helps to maintain its shape but loss of turgor pressure during the stress allows the leaves to roll up. During drought, the loss of moisture through vacuoles induces bulliform cells to cause the leaves of many grass species to close as the two edges of the grass blade fold up toward each other. Once adequate water is available, these cells enlarge and the leaves open again.
How many tissue systems are suggested by Sachs?
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Two
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Three
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Four
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Five
Two or more tissues together constitutes the tissue system. The activities of the constituent tissues are responsible for the major function, although they are different in structure and origin. All the different type of tissues in a plant that perform the similar basic function, irrespective of their location is known as tissue system.
In respect of many grasses, the presence of motor cells in the upper epidermis of leaves is to
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Increase the surface area of the leaf
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Store large amount of water
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Check transpiration by reducing the surface area of the leaf
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Bear unicellular trichomes
The stems and leaves of grasses are rough due to
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Calcium carbonates
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Resins
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Silica
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Calcium oxalate
The grass leaves are linear in shape and sessile and are rough in texture due to the presence of cork cells in the epidermis and deposition of silica material. The process of deposition of silica material over the epidermis is known as silicification. It checks the transpiration rate and prevents the entry of pathogens and gives stiffness to the lamina.
Periblem form
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Endodermis
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Cortex
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Both A and B
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Epidermis
Histogen theory (By Hanstein 1870) concludes that shoot apical meristem consists three distinct zones.
If all the lenticels of stem are blocked, the first to die will be
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Leaves
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Shoot tips
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Roots
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None of the above
A lenticel is mainly the opening present on the periderm of the secondarily thickened organs and the bark of woody stems and roots of dicotyledonous flowering plants. It is a porous tissue consisting of cells with large intercellular spaces. It helps in the direct exchange of gasses between the internal tissues and atmosphere through the bark, which is otherwise impermeable to gasses. Lenticels are found in most of the woody trees but absent is woody climbers. If lenticels are blocked then root will die first due to lack of gaseous exchange. Thus, option C is correct.
In the leaf, vascular bundles are found in
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Veins
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Palisade tissue
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Upper epidermis
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Lower epidermis
A vascular bundle is a part of the transport system in vascular plants. The transport itself happens in vascular tissue, which exists in two forms: xylem and phloem. These are generally present in the veins of the leaf where the xylem channelizes the water and phloem conducts the prepared food from the source to the sink.
Bulliform cells that help in the folding down of lamina in drought are present in the epidermis of
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Monocotyledonous grass leaf
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Dicotyledonous leaf
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Both A and B
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None of the above
Bulliform cells are so called because of its peculiar bubble shape. It mainly occurs on the upper surface of the leaves present in grasses. Water present in these cells helps to maintain its shape but loss of turgor pressure during the stress allows the leaves to roll up. During drought, the loss of moisture through vacuoles induces bulliform cells to cause the leaves of many grass species to close as the two edges of the grass blade fold up toward each other. Once adequate water is available, these cells enlarge and the leaves open again. Bulliform cells are present in only monocot leaf and absent in dicot leaf.
Thus, the correct answer is option A.
In which plant part, laticiferous gland are found?
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Cortex
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Epidermis
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Endodermis
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Vascular bundle
Laticiferous vessels are the specialized thin walled parenchymatous cells that secrete latex and are found in the cortex. They lack pits and are composed of cellulose and hemicelluloses and serve to secrete latex.