Solve these clues to fill the grid.
- Respiratory disorder characterized by wheezing
- 2 Across
- The passages through which air enters and leaves the body
- 4 Across
- A mechanical device in a camera that controls size of aperture of the lens
- 7 Across
- Inflammation of the membranes lining the ___ tubes
- 10 Across
- A heavy odorless colorless gas formed during respiration and by the decomposition of organic
- 11 Across
- Any of the smallest ___ ducts (plural)
- 12 Across
- Expectorated matter
- 14 Across
- The thin serous membrane around the lungs and inner walls of the chest
- 15 Across
- Organ that pumps blood around the body
- 16 Across
- A cartilaginous structure at the top of the trachea
- 1 Down
- One of the tubules forming the respiratory system of most insects and many arachnids
- 3 Down
- A sudden noisy expulsion of air from the lungs that clears the air passages
- 5 Down
- Either of two saclike respiratory organs in the chest of vertebrates (plural)
- 6 Down
- The metabolic processes whereby certain organisms obtain energy from organic molecules
- 8 Down
- A ___ in which ___ circulates (plural)
- 9 Down
- Gas in the air that we need to breathe
- 13 Down
