Surfactant: A fluid secreted by the cells of the alveoli (the tiny air sacs in the lungs) that serves to reduce the surface tension of pulmonary fluids; surfactant contributes to the elastic properties of pulmonary tissue, preventing the alveoli from collapsing.urfactant: A fluid secreted by the cells of the alveoli (the tiny air sacs in the lungs) that serves to reduce the surface tension of pulmonary fluids; surfactant contributes to the elastic properties of pulmonary tissue, preventing the alveoli from collapsing.
Guy Fawkes' Day is not a public holiday. Businesses, organizations and schools are open as usual. Public transport services run to their normal timetables. Some organizations, communities and municipalities may organize public bonfires or displays of fireworks on or around November 5.
Labor Day 2017 and 2018. Labor Day is observed in the U.S. on every first Monday in September as a day to recognize the contributions of American workers of all industries to the U.S. economy. It is also meant to give workers a well-earned day off to relax at home or to get out for recreation.