Military forces have worn distinctive uniform items for centuries to create a psychological advantage and boost their esprit de corps, but the military use of berets is a relatively recent phenomenon. In the 16th and 17th centuries, the Blue Bonnet became a de facto symbol of Scottish Jacobite forces.
Muscle cells have adapted to their job by contracting and relaxing.  When calcium levels are increased the muscle cells contract. On the  other hand, when calcium levels droâ¦p the muscle cells get relaxed.
These filaments are primarily structural in function and are an important component of the cytoskeleton, along with microtubules. In association with myosin, microfilaments help to generate the forces used in cellular contraction and basic cell movements.They enable a dividing cell to pinch off into two cells and are involved in amoeboid movements of certain types of cells. They also enable the contractions of muscle cells.hese filaments are primarily structural in function and are an important component of the cytoskeleton, along with microtubules. In association with myosin, microfilaments help to generate the forces used in cellular contraction and basic cell movements.