BIG LUNGS ON THE TENNIS COURT

Look out Maria – you’re meant to hit the ball, not swallow it! No matter what sort of tennis you play, we all know your lungs work well - some say too well.

So are our lungs just wind bags or is there some delicate engineering down there?
How about:

·       2,400 kilometres of airway

·       300 - 500 million air sacs (alveoli) supply their own surfactant to prevent collapse

·       alveoli walls only 10 microns thick, separating blood vessels from the inhaled air

·       992 kilometres of blood capillaries to facilitate gas exchange

Impressive? Well how about an internal surface area of at least 70 square metres - the size of A PLAYER’S TENNIS COURT!

Our lungs are over-engineered, with surplus capacity that proves useful at high altitude, after suffering injury or following the onset of tuberculosis, emphysema from mining, smoking…

So why don't we gradually drown in the muck that goes south?
Some cells produce mucous to trap inhaled debris and bacteria while others have fine hairs (cilia) which rhythmically beat towards the throat, driving that muck back up north. How handy is that!

What else do our lungs do? Alter blood pH, filter small venous clots, filter blood microbubbles, provide airflow for vocal sounds, provide a reservoir for blood………

Well is this all just good luck, or is there a Creator who has provided for us generously with these bellows we take so much for granted?   Perhaps He anticipated the Earth’s atmosphere would offer a reduced oxygen concentration after the Great Flood??

By the way, every mammal relies on the same standard of engineering design.

      Acknowledgements: 
        wikipedia.com
        Anatomica, Global Book Publishing, Sydney, 2006
        Photo credit: globoesport.globo.com