Vessels and companion cells are respectively present in the xylem and ...
Phloem elements do typically have sieve plates instead of final walls. Sieve-tube members of angiosperms are associated by living companion cells. The phloem is the principal food-conducting tissue of vascular plants. Its elements are elongated, just like those of the xylem.
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Vessels and companion cells are respectively present in the xylem and ...
Introduction
The transport systems in plants are crucial for the movement of water, nutrients, and sugars. The xylem and phloem are two types of vascular tissues responsible for these functions, with specific cell types associated with each.
Xylem: Vessels
- In angiosperms (flowering plants), the xylem primarily consists of vessels.
- Vessels are tube-like structures that facilitate the efficient upward movement of water and dissolved minerals from the roots to the leaves.
- This structure allows for a more rapid transport compared to tracheids, which are found in gymnosperms and some lower vascular plants.
Phloem: Companion Cells
- In angiosperms, phloem tissues include companion cells, which are specialized parenchyma cells.
- Companion cells play a vital role in the transport of sugars produced during photosynthesis from the leaves to other parts of the plant.
- They are closely associated with sieve tube elements, assisting in loading and unloading of nutrients.
Comparison with Other Plant Groups
- Gymnosperms: Lack vessels; they primarily have tracheids for water transport.
- Pteridophytes: Also do not possess true vessels; they primarily utilize tracheids.
- Bryophyta: Lacking vascular tissues entirely, they rely on diffusion for transport.
Conclusion
Thus, the correct answer is option 'C', as vessels and companion cells are characteristic features of angiosperms, differentiating them from other plant groups in their efficiency of transport systems.