Final answer:
Cell membranes are indeed flexible and fluid, which is true. Their fluidity allows for selective permeability, flexibility in shape, and the movement of membrane components necessary for cellular transport and homeostasis maintenance.
Step-by-step explanation:
The statement that cell membranes are flexible and fluid is True. The fluidity of the cell membrane is crucial because it confers flexibility that allows the membrane and its components to move as required for transport processes. The fluid mosaic model describes the cell membrane as a dynamic structure where lipids and proteins move laterally within the membrane, providing the mosaic-like appearance. Although the membrane is flexible, it maintains a fairly rigid structure to prevent bursting from penetration or osmotic pressure. Fluidity and membrane functions are interdependent; for instance, the membrane fluidity is influenced by the saturation level of lipid fatty acids and by temperature.
Membrane fluidity is advantageous for cells because it supports various critical functions including the transit of materials essential for maintaining homeostasis, the cell’s ability to change shape, and the mobility of membrane components necessary for signaling and interaction with the environment. Furthermore, the plasma membrane is segregated into regions with varying properties of fluidity and selective permeability, which is essential for the membrane's function in regulating the movement of molecules.