The cork cambium, cork and secondary cortex are collectively called:
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Solution
Phellem, phellogen and phelloderm are collectively called periderm.
In land plants, the guard cells differ from other epidermal cells in having :
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Solution
Guard cells differ from epidermal cells in having chloroplast. The cell wall of guard cells are not uniform,inner walls are thicker than the outer walls, epidermal cells are uniformly thin.
A bicollateral vascular bundle has which of the following arrangement of tissues ?
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Solution
In a bicollateral vascular bundle, the middle xylem is bounded by outer phloem and outer cambium. The inner face of the xylem has inner cambium and inner phloem.The bicollateral bundle is always open
Ground tissue includes
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Solution
Ground tissue includes all tissues except epidermis and vascular bundles. The ground tissue comprises the bulkof the primary plant body. Parenchyma, collenchyma and sclerenchyma cells are common in the ground tissue.
Heartwood differs from sapwood in:
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Solution
Heartwood differs from sapwood in having dead and non-conducting elements. In old trees, the inner region that comprises dead elements with highly lignified walls is called heartwood. Heartwood does not conduct water but gives mechanical support to the stem. On the other hand,the peripheral region, which is lighter in colour are called sapwood. It is involved in the conduction of water and minerals from root to leaf.
Which one of the following is not a lateral meristem?
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Solution
Meristem is divided on the basis of position in plant bodies into apical meristem, lateral meristem and intercalary meristem. Lateral meristem is present on the lateral sides, that is fascicular and interfascicular cambium and cork cambium (phellogen).
The sugarcane plant has
The chief water conducting elements of xylem in gymnosperms are:
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Solution
Tracheids are chief water conducting elements of xylemin gymnosperms. They are devoid of protoplasm and hence dead. The wall constituting the tracheids is hard,thick and lignified. These are elongated cells with tapering ends.
Reduction in vascular tissue, mechanical tissue and cuticle is characteristic of:
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Solution
Reduction in vascular tissue, mechanical tissue and cuticle is characteristic of hydrophytes.
In barley stem vascular bundles are :
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Solution
In barley stem vascular bundles are closed and scattered.They are open only for a hours in the day time and never open at night, e.g., Cereals.