- Xylem contains tracheids, vessels, xylem parenchyma and xylem fibre.
- Tracheids: They are elongated, tubular dead cells with tapering end walls.
- Vessels: These are also known as trachea. They are elongated, tubular dead cells. They are joined to each other by end to end forming a continuous pipe. The cells are thick and lignified.
- Xylem parenchyma: They are also called wood parenchyma. This is the only living tissue of xylem.
- Xylem fibre: They are dead cells with thick walled fibre.
- Phloem consists of sieve tubes, companion cells, phloem parenchyma and phloem fibres.
- Sieve tubes: These are elongated, tubular living cells arranged in a row, with their perforated end walls forming a sieve. They are non-nucleated. Their protoplasm are inter-connected through sieve plates. They possess vacuoles.
- Companion cell: They are elongated, lens-shaped cells containing dense cytoplasm and prominent nuclei. These cells maintain connection with sieve cells through pits.
- Phloem parenchyma: They are living thin walled parenchyma cells.
- Phloem fibre: They are also known as bast fibre. They are elongated fibre like sclerenchymatous dead cells with thick walls containing pits and interlocked ends. Phloem fibre are the only dead cells in phloem.
Hope you could get an idea from here.
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Not always, the toxins may have been absorbed by the body and released in urine
Adenine and thymine
cytosine to guanine
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Answer:
Urban explosion would be a concern in regard to environmental science because of two major things.
Explanation:
There is the amount of space the growing cities will take up that takes away from the environment, and the pollutants the cities produce.
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Melina B.
Answer: Carbon dioxide
Explanation:
The chemolithophs are the prokaryotes which uses inorganic matter in order to make organic materials for the other processes.
These organism get energy by the oxidation of the inorganic compounds. The organism such as human beings breaks down the organic compounds in order to get energy and nutritional building block.
The macro molecule used by the organism is carbon dioxide.
