Across
- 1. – The microscopic air sacs where the "trade" of gases happens.
- 2. – The dome-shaped muscle that controls the pressure in your chest.
- 4. flowing backward.
- 5. – The thinnest blood vessel that wraps around the air sacs.
Down
- 1. – The specific molecule used as "energy currency" by your cells.
- 2. – The process of molecules moving from a crowded area to a less crowded area.
- 3. – The "powerhouse" of the cell where energy is created.