Explain how treadmilling contributes to actin-based motility in crawling cells. be specific in why both actin filament growth a d shrinkage are necessary.

The actin filaments in cell constantly grow and shrink. This occurs through addition or removal of subunits. The two ends of actin filament have different dynamics of addition and removal of subunits. That way, one end of actin filament will grow and one end will shrink so it seems like the filament is moving. This phenomenon, known as treadmilling is characteristic for both actin filaments and microtubules.

Iwould say silver and gold