Plants cells has large vacuole, chloroplast and a cell wall while animal cells don't have those features.
That element is <span>Nitrogen.</span>
The total volume of the gas-exchanging region in the lung is called alveolar volume.
The alveolus is an air sack-like organ in the end of the respiratory airway. The alveolus is the site where gas-exchanging happens, so only air inside alveolus that will undergo actual exchange. Air in bronchus or trachea wouldn't do exchange
