filament

biology

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June 26, 2026

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In biology, a filament is a thin, flexible, thread-like structure. Within cells, there are several types of protein filaments that form the cytoskeleton, providing structural support and enabling movement.1

Key types of cellular filaments include:
* Actin filaments: These are dynamic structures essential for cell shape, movement, and intracellular processes like cytokinesis. In muscle cells, actin works with myosin to cause contraction.21
* Microtubules: These are hollow cylinders formed from tubulin proteins. They are crucial components of the cytoskeleton, cilia, flagella, and the spindle apparatus during cell division.34
* Intermediate filaments: These are more stable filaments that primarily reinforce cell structures, such as supporting the nucleus.5

These filaments work with various accessory proteins to carry out diverse cellular functions.1

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plant development
Body plans
…illustrates the transition from a filamentous to a highly organized three-dimensional growth form. The moss spore germinates into a filamentous plant, the protonema, which later produces a leafy shoot. This type of transition from simple to more complex growth form is accompanied by the synthesis of new kinds of ribonucleic…
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…illustrates the transition from a filamentous to a highly organized three-dimensional growth form. The moss spore germinates into a filamentous plant, the protonema, which later produces a leafy shoot. This type of transition from simple to more complex growth form is accompanied by the synthesis of new kinds of ribonucleic…
Read More