During activation, the single chain protein of the native factor XII is cleaved into two chains (50 and 28 kDa), which remain linked by a disulphide bond. The light chain (28 kDa) contains the active site and the molecule is referred to as activated Hageman factor (factor XIIa).
A spring tide refers to the 'springing forth' of the tide during new and full moon. A spring tide is a common historical term that has nothing to do with the season of spring. Rather, the term is derived from the concept of the tide springing forth.. Spring tides occur twice each lunar month all year long without regard to the season.
Some background. What are spring tides? Around each new moon and full moon, the sun, Earth, and moon arrange themselves more or less along a line in space. Then the pull on the tides increases, because the gravity of the sun reinforces the moonâs gravity. In fact, the height of the average solar tide is about 50% the average lunar tide. Thus, at new moon or full moon, the tideâs range is at its maximum. This is the spring tide: the highest (and lowest) tide. Spring tides are not named for the season. This is spring in the sense of jump, burst forth, rise. So spring tides bring the most extreme high and low tides every month, and they happen around full and new moon.