Step 1: Analyze Cytoskeleton Functions:
The cytoskeleton is an elaborate network of filamentous proteinaceous structures in the cytoplasm. Its main functions are:
Mechanical support: Yes (I).
Motility: Yes (II) (e.g., cilia, flagella, amoeboid movement).
Maintenance of shape: Yes.
Step 2: Analyze Non-Functions:
III. Intercellular transport: The cytoskeleton helps in \textit{intra}cellular transport (within the cell). \textit{Inter}cellular transport (between cells) is primarily facilitated by plasmodesmata and vascular tissue, not the cytoskeleton directly.
IV. Mesosome formation: Mesosomes are infoldings of the plasma membrane found in prokaryotes (bacteria). The cytoskeleton (microtubules, etc.) is a characteristic of eukaryotes.
Step 3: Conclusion:
Functions III and IV are not related to the cytoskeleton.