The nuclear envelope's structure is determined by a network of intermediate filaments (protein filaments).

'Hair' is a protein filament that epidermal growth from hair follicle deep within the dermis.

Some phenomena that profile a protein filaments' dynamics are:

A scleroprotein forms long protein filaments, which are shaped like rods or wires.

These are flame-shaped masses inside dead brain cells formed from coiled, rope-like protein filaments.

The microscopic "hairs" of these cells are structural protein filaments that project out into the fluid.

Although the number of muscle fibers may increase, strength is gained chiefly because added protein filaments increase the size of each fiber.

Muscle cells contain protein filaments that slide past one another, producing a contraction that changes both the length and the shape of the cell.

Within the cells of the muscle are myofibrils, which themselves are bundles of protein filaments.

It consists of a series of protein filaments that shorten rapidly upon exposure to calcium.