Screen Doors and Saunas

Every incoming breath faces a treacherous ride before it arrives at the relatively peaceful area of your lungs. The fast and furious journey through your nasal cavities flings the breath around like a small boat shooting the rapids.

There is only a second or less to warm, moisten and capture every bit of grit and grime from a breath before it descends into your vulnerable lungs. Lung tissue has heavy responsibilities and is not built to defend itself. That security duty must be completed pretty much by the time the air leaves your head.

Both nostrils are lined with stiff hairs. Like screen doors, they keep out the big stuff like gnats and grit. Then the breath passes through adjacent “saunas” with warm moist walls. The sauna walls are lined with strategically placed floppy shelves (the turbinates) that bounce the air around, slamming it again and again against the surfaces of the inner nose.

The entire route is covered with really sticky mucus. Every time the air is tossed against the “fly paper” some of its garbage sticks. Remember that all mucus is constantly moving toward an exit where you periodically swallow, spit or blow out the contaminated mess.

Having been forced through the tumbling of the nasal cavities, the incoming air almost immediately encounters a sharp right turn just before the downward journey into the throat. More grit is dropped when the air hits that sudden bend, the same way silt is dropped when the stream makes a sharp turn.

Be well. Breathe beautifully.

LINK: Snot Is Your Friend

The Extraordinary Exchange

A net of blood vessels (so fine that the blood must squeak through one cell at a time) is laced tightly around each air sac (alveolus). The alveolar walls here are as thin as soap bubbles about to burst. This ingenious design allows oxygen to pass easily from the incoming breath, through the thin shared wall of the air sac and blood vessels and finally into the blood stream.

While the blood is sucking up oxygen from the air sac, it simultaneously gives up its carbon dioxide into that same tiny sac. Carbon dioxide is spent fuel that now must be carried away in the air about to be exhaled from all alveoli.

Your blood at that point has been refreshed with a new supply of oxygen and is ready to resume its unending duties on your behalf. It is the extraordinary exchange of gases in this inner sanctum that fuels all that you do, all that you are.

Be well. Breathe beautifully.

Link: The Path From Throat To Lungs

The Path From Throat To Lungs

Your windpipe is a large flexible hose held open by C-shaped pieces of cartilage open toward the spine (accommodating lumps of food traveling down the adjacent esophagus). The windpipe divides in two just behind your heart, one hose descending toward your right lung and the other toward the left. At this point these two slightly smaller hoses (the main bronchi) enter your lungs, along with essential blood vessels and nerves.

Because your large muscular heart is tucked between the lungs, and is positioned slightly off to the left, things get crowded on that left side. Therefore, you have only two lobes within the left lung as well as a noticeably smaller descending bronchus. The roomier right lung has three lobes, with a larger bronchus.

The bronchial hoses now begin to divide again and again creating progressively narrower bits of hose. This bronchial branching is often described as an inverted tree. Imagine the windpipe as the trunk, the bronchi as the main branches, the progressively narrow bits of air hose as the smaller branches and stems.

By now the microscopic subdivisions of air hose have become too narrow for cartilage-ring support. At the very end of each of the smallest subdivisions of the bronchial tree is a cluster of air sacs (the alveoli). Imagine a microscopic cluster of hollow grapes growing from a tiny hollow stem. Lung tissue is made up of trillions of these microscopic clusters. The cleaned warm oxygen-rich air at this point is embraced by your blood stream.

Be well. Breathe beautifully.