Which one of the following statement pertaining to plant structure is correct?a)Cork lacks stomata but lenticels carry out transpirationb)Passage cells help in transfer of food from cortex to phloemc)Sieve tube elements possess cytoplasm but no nucleid)The shoot apical meristem has a quiescent centreCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

Sieve tube members are living cells (which doesn't contain nucleus) that are responsible for transporting carbohydrates throughout the plant ... sieve tubes members do need have ribosome or a nucleus and thus need companion cells to help them to transport molecule

Answer

Sieve elements' major function includes transporting sugars over long distance through plants by acting as a channel. Sieve elements elongate cells containing sieve areas on their walls. Sieve elements typically contain cytoplasm but lack a nucleus and contain none to a very small number of ribosomes.

Answer

The correct statement pertaining to plant structure is option C, which states that sieve tube elements possess cytoplasm but no nuclei.

Explanation:

- The sieve tube elements are a type of cells found in the phloem tissue of plants. They are responsible for transporting sugars and other organic molecules from the leaves to other parts of the plant, such as the roots and fruits.

- Sieve tube elements are elongated cells that are arranged end to end to form sieve tubes. These cells have perforated sieve plates at their ends, allowing for the movement of materials between adjacent cells.

- Unlike most other plant cells, sieve tube elements lack nuclei. This is because the absence of nuclei allows for a more efficient flow of materials through the sieve tubes.

- The cytoplasm of sieve tube elements is responsible for carrying out the metabolic functions required for the transport of sugars. It contains various organelles and a specialized endoplasmic reticulum, called the sieve element reticulum, which is involved in the transport of sugars.

- The absence of nuclei in sieve tube elements is compensated by companion cells. Companion cells are closely associated with sieve tube elements and provide them with the necessary cellular machinery for metabolic activities. Companion cells have dense cytoplasm, numerous mitochondria, and a large nucleus, which supplies the sieve tube elements with energy and proteins.

- The transport of sugars and other organic molecules in sieve tube elements occurs through a process called translocation. Translocation involves the loading of sugars into sieve tube elements in the source tissues (e.g., leaves) and the unloading of sugars in the sink tissues (e.g., roots or fruits).

Overall, the absence of nuclei in sieve tube elements allows for a more efficient flow of materials through the phloem tissue, while the presence of companion cells ensures the metabolic activities required for translocation.

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