④B d Na permea ity barrier ② Organiz anc ization of funoon Nucleus (5) Cell-to-cell communication Transp proce Nutrients (4 Signal detectionTHNMR YAN 细胞膜的功能概述 1. Define the boundaries of the cell and its organelles. 2. Serve as loci for specific functions. 3. provide for and regulate transport processes. 4. contain the receptors needed to detect external signals. 5. provide mechanisms for cell-to-cell contact, communication and adhesion ✓ ✓ ✓