The Treaty of Kanagawa was an 1854 agreement between the United States of America and the government of Japan. The treaty, which was essentially imposed on the Japanese by threat of force, opened two Japanese ports for trade with American ships. The treaty was the first modern treaty Japan had with a western nation.
Platelets have no cell nucleus: they are fragments of cytoplasm that are derived from the megakaryocytes of the bone marrow, and then enter the circulation. These unactivated platelets are biconvex discoid (lens-shaped) structures, 2â3 Âµm in greatest diameter.
Platelets provide critical protection for our blood vessel walls, helping clog wounds and stopping the loss of blood. Platelets are not completely formed cells, but merely cell fragments and consequently much smaller than red cells. They account for less than one percent of total blood volume and live for about 10 days. Let's take a closer look at how the clotting process works.