Ignore this I just need to answers questions to be able to ask questions
Blood
Blood is the transport fluid circulating in the body and is responsible for the transport of substances from one point to another. Blood is composed of red blood cells, white blood cells, platelets and plasma. All of these components work together and transport substances such as oxygen, glucose and amino acids to the cells and remove waste substances such as carbon dioxide and urea away from the cells.
This is true that the pressure in the mesosphere is so low that a person could not be in this layer without a spacesuit.
The mesosphere is the region of the earth's atmosphere which is above the stratosphere and below the thermosphere. It has a very low temperature and pressure. The top of the mesosphere is the coldest part of Earth's atmosphere.