Final answer:
Actin filaments are thin and flexible structures composed of two intertwined strands of actin protein, playing a crucial role in cellular movement and muscle contraction.
Step-by-step explanation:
Actin filaments, also referred to as microfilaments, are involved in various cellular functions, including cellular movement and muscle contraction. These filaments are composed of two intertwined strands of the globular protein actin, making them thin and flexible.
They play a key role in cellular processes such as ameboid movement, cytoplasmic streaming, and the contractile ring formation during cell division. In muscle cells, actin filaments are known as thin filaments and work in conjunction with thick filaments of the myosin protein to allow muscle contraction. Due to their polymerization and depolymerization dynamics, they can reorganize quickly, enabling cells to change shape and move.
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