Excitation of the sarcolemma is coupled or linked to the contraction of a skeletal muscle fiber. what specific event initiates the contraction?

the truman doctrine was an american foreign policy whose stated purpose was to counter soviet geopolitical expansion during the cold war. it was announced to congress by president harry s. truman on march 12, 1947, and further developed on july 12, 1948, when he pledged to contain threats to greece and turkey.