25. What structure in a plant cell acts as a barrier and provides support to the cell?
Answer: D
The cell wall acts as a barrier and provides support to the cell.
The cell wall is a rigid structure that surrounds the plant cell membrane, providing both support and protection. It is essential for maintaining the shape of the cell and preventing excessive water uptake.
A) Chloroplast
Chloroplasts are the organelles responsible for photosynthesis in plant cells, converting light energy into chemical energy. They do not function as a barrier or provide structural support to the cell, making this option incorrect.
B) Cell membrane
The cell membrane controls the movement of substances in and out of the cell and provides some structural support. However, it is not as rigid as the cell wall and does not serve as the primary barrier or support structure for plant cells, rendering this option insufficient.
C) Xylem
Xylem is a type of tissue responsible for the transport of water and nutrients within the plant. While it is important for the plant's overall structure and function, it is not a cell structure and therefore does not act as a barrier or provide support to individual plant cells.
D) Cell wall
The cell wall is the correct answer as it is the primary structure that serves as a protective barrier for plant cells. It provides rigidity and support, helping to maintain the cell's shape and withstand external pressures, which is crucial for the overall integrity of the plant.
Conclusion
The cell wall is definitively the correct answer as it uniquely serves as both a barrier and a support structure for plant cells. In contrast, the other options either serve different functions or do not pertain to the structural support of the cell itself. Thus, the cell wall stands out as the essential component fulfilling the requirements of the question.