Which part of the cell is compared to a medieval city wall due to its strength?

The cell wall is aptly compared to a medieval city wall because it provides strength and structural support to the cell. Just like a city wall protects and maintains the integrity of a city, the cell wall serves as a rigid outer layer that surrounds the plasma membrane in plant cells, fungi, and some bacteria. This structure is primarily composed of cellulose in plants, which gives it its strength and durability. It helps the cell withstand turgor pressure, ensuring that the cell maintains its shape and is less susceptible to external forces.

In contrast, the cell membrane, while also involved in protection and maintaining the integrity of the cell, is more flexible and dynamic compared to a rigid wall. The cytoplasm is the thick fluid within the cell, consisting of various organelles and structures, but it does not serve a protective role. Chloroplasts are specialized organelles responsible for photosynthesis in plant cells and do not provide structural support. Thus, the comparison of the cell wall to a medieval city wall highlights its essential role in the protection and stability of plant cells.