The answer to this question would be: vitamin
Some bacteria can produce vitamin K2 in the intestine. Other bacteria also able to change vitamin K1 into vitamin K2. But the amount produced is not much, so human still need to fulfill it from the diet. Vitamin K has a role in calcium regulation and in blood clotting pathway.
Answer:
Free fall.
Explanation:
When astronauts sleep in space, they sleep in small cabins or in sleeping bags that are attached to the wall or ceiling of the station. Everything is weightless as there’s no gravity in space. So while sleeping there is a chance of floating around and bumping into things. Astronauts use sleeping bags that can be tethered to the wall or ceiling to solve this problem. Also the tethered sleeping bags provide a normal sleeping environment to the astronauts as they can feel pressure on their back and head. Their sleeping cabin is well ventilated as they can wake up with breathing trouble as a result of the inhalation of their own exhaled carbon dioxide which formed around their heads as a bubble. They use earplugs and a sleep mask to block the noise and light and can sleep vertically or horizontally. Compared to earth, sleeping is a bit different in space.
