Q.Which of the following is not a function of cytoskeleton in a cell?

The cytoskeleton is often called the cell's scaffolding—a dynamic network of protein filaments that extends throughout the cytoplasm. To understand what it can and cannot do, picture it as an internal skeleton that gives the cell structure, highways for cargo movement within the cell, and the machinery for shape changes. The key word here is internal: the cytoskeleton operates inside a single cell.

Let's examine each function:

1. Intracellular transport (A) — TRUE function

   Motor proteins like kinesin and dynein walk along microtubules (one type of cytoskeletal filament), carrying vesicles, organelles, and other cargo from one part of the cell to another. Think of microtubules as railway tracks and motor proteins as locomotives. This is how mitochondria reach the cell periphery or how neurotransmitter vesicles travel down an axon.

2. Mechanical support (B) — TRUE function

   The cytoskeleton provides structural integrity. Intermediate filaments resist tension, microtubules resist compression, and actin filaments form a cortical mesh beneath the plasma membrane. Without this framework, cells would collapse under their own membrane tension or external forces.

3. Intercellular transport (C) — NOT a function …

The concept first

An animal cell has no cell wall, yet it holds its shape, moves, divides and shuttles vesicles around. It does all this with an internal protein scaffolding called the cytoskeleton. Three filament families make it up:

1. Microfilaments — polymers of the protein actin, ~7 nm across; they drive cell shape change, cytoplasmic streaming and the cleavage furrow.
2. Intermediate filaments — ~10 nm, of proteins such as keratin/vimentin; purely mechanical, they resist tension.
3. Microtubules — hollow tubes of tubulin, ~25 nm; they form the spindle, the cores of cilia and flagella, and act as tracks for motor proteins.

Notice what the list does not contain: lipids and polysaccharides. Lipids build membranes; polysaccharides build cell walls and the glycocalyx.

Step-by-step

Step 1 — Test the Assertion. "Cytoskeleton ... is made up of a network of filamentous lipids and polysaccharide structure." The chemical identity is simply wrong — filaments are protein polymers. A is FALSE. …