Answer:
The xylem is located in the root, stem and the leaves of a plant.
The xylem contains dead cells arranged end-to-end forming continuous vessels. They have a hollow central space (lumen) through which water passes. They walls contain lignin.
The xylem carries water and minerals, up from the roots to the rest of the plant.
5,996,544.
I hope this helps
The air outside your body because when you tried to hold your breath the pressure builds and forces your body to breath by letting out the air but depending the altitude you are the pressure can change hope this helps
