Cumberland Times-News

Bob Doyle - Astronomy

July 6, 2014

A long and winding road faces our food

Last week’s column dealt with organs you can do without, our DNA (molecular blueprint for our bodies) and hair. My reference is “Body: Discover What’s Beneath Your Skin,” a Miles Kelly Book, written by John Farndon and Nicki Lampon and published in 2010. This column will consider finger and toe nails, breathing and coughing, saliva, mucus and your food’s long and torturous journey. Most cities and mid sized towns have nail shops where you can have your finger nails and toe nails adorned. Nail painting can be traced back 5,000 years.



Both finger and toe nails are formed from dead cells mixed with keratin, a protein. This is the same substance that antlers are made of. Nails grow from a nail root, hidden by a flap of skin called a cuticle. The lighter part of the nail is called the lunula, resembling the moon’s shape.



Finger nails grow 0.5 millimeters or 0.02 inches each month. Nails grow faster in the summer and more slowly in the winter. If you are right handed, the finger nails on that hand will grow faster than the fingers on your left hand. A similar statement applies to left handed people.



Breathing is automatic with an average breath taking in 0.4 liters or nearly one pint of air every four seconds. Your diaphragm arches upward against your lungs as you exhale and downward as you inhale.



We breathe to get oxygen, which makes up 21 percent of the air. The airways are coated with mucus to trap dust and other small particles so they don’t go into your lungs. Your lungs have about 300 million alveoli (air sacs) where the oxygen can pass into capillaries and bind with a red blood cell.



The carbon dioxide (our waste gas) is dissolved in the blood plasma. Then the blood carries its load of carbon dioxide into the alveoli where it is released to the air there and discharged upon exhaling.



Coughing is the body’s way of removing dust or irritants in the airways and lungs. When you cough, you are expelling 2.5 liters of air out of your lungs. Coughing is usually a reflex action, although you can cough voluntarily.



Saliva is fluid that is mixed with your
food as you chew it in your mouth. It is made by salivary glands in the mouth. Saliva contains enzymes that start the digestion process. Your mouth makes up to 1.5 liters of saliva a day.



Mucus is valuable in trapping small particles in the air that we breathe. Your stomach has a protective layer of mucus on its interior lining to prevent the strong gastric acids from digesting the stomach itself. Your small intestine is also lined with a protective layer of mucus to keep the small intestines from dissolving itself.



Your digestive tract is nearly six times as long as you are tall. It needs to be that long so you can properly extract nourishment from your food. After being chewed, the food passes down the esophagus into your stomach.



An empty stomach is only 0.5 liters in volume (about a pint) but after a big meal can stretch to four liters in volume. The stomach churns the food into a gooey substance called chyme, taking up to five hours to process the food before it is released. Next is the small intestine, about six meters or nearly 20 feet long. In the first part of the small intestine, the chyme is infused with enzymes and bile to break it down into molecules. In the second part of the small intestine, the food is absorbed.



All through the digestive tract the food is pushed along by waves of contraction called peristalsis. This action is involuntary; your innards know what to do with food.



The main part of your large intestine is the colon, almost as long as your height. Here is where liquids are converted into solid waste. Your colon soaks up to three quarts of water every day.



There is a vast multitude of bacteria living in the colon (dozens of trillions). The bacterial residents there make vitamins K and B. Then the feces collect at the end of the colon and await a time when they can be excreted.

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Bob Doyle - Astronomy
  • It’s hotter here than in D.C. or Baltimore

    At this time of the year, the weather is a frequent subject of conversation, particularly the temperatures. We are now in the “Dog Days,” usually the hottest days of the year. The term comes from our sun appearing to be near the “Dog Star” (Sirius) and the “Little Dog Star” (Procyon). In reality, the sun is now about 94.5 million miles away while Sirius is 8.6 light years away with Procyon at 11 light years distance. Sunlight takes only 507 seconds to reach us, while the two dog stars’ light takes about a decade to travel to our eyes. So our sun is in the same direction (but not distance) as these two bright winter evening stars.

    July 20, 2014

  • Fronts, highs, lows determine weather

    Weather news on television and internet focus on violent weather, extreme temperatures and flooding.

    July 13, 2014

  • A long and winding road faces our food

    Last week’s column dealt with organs you can do without, our DNA (molecular blueprint for our bodies) and hair. My reference is “Body: Discover What’s Beneath Your Skin,” a Miles Kelly Book, written by John Farndon and Nicki Lampon and published in 2010. This column will consider finger and toe nails, breathing and coughing, saliva, mucus and your food’s long and torturous journey. Most cities and mid sized towns have nail shops where you can have your finger nails and toe nails adorned. Nail painting can be traced back 5,000 years.

    July 6, 2014

  • Here’s a look at what goes on inside you

    In high school, my favorite science course was biology. I can remember Mr. Munley in his wheelchair. Our class went on a field trip to the University of Miami Medical School where we saw the cadavers used by the medical students.

    June 28, 2014

  • Moon-watching easy when you know how

    Long before the first writing (scratches on clay tablets) appeared, our early ancestors noticed that the moon went through a regular cycle of shapes in about 30 days.

    June 21, 2014

  • Here’s how you can tell the stars, planets

    How can one tell one star from another at night? It’s a matter of knowing the sky areas (constellations).

    June 15, 2014

  • Smithsonian guide to stars is a good one

    At a local book store, I yielded to temptation and bought “Stars and Planets,” a Smithsonian Nature Guide written by four authors. Dinwoodie, Gater, Sparrow and Stott. It’s another Dorling Kindersley product with ISBN 978-0-7566-9040-3 and a 2012 copyright. “Stars and Planets” is a trade size paperback that is beautifully illustrated with appealing diagrams. “Stars and Planets” begins with the biggest topic, the Universe. There is a striking visual showing the known universe on the hugest scale, a delicate lacework of superclusters of galaxies with large voids. It resembles a bubble bath!

    June 8, 2014

  • Think a little more and be less frazzled

    Last Sunday’s column dealt with using technology carefully in education. What about technology in everyday life? There is a marvelous book “The Thinking Life,” by P.M. Forni, of The Johns Hopkins University which addresses this issue as well as timeless suggestions for living by Greek and Roman thinkers. “The Thinking Life: How To Thrive in the Age of Distraction” was published by St. Martin’s Press in 2011 with ISBN 978-0-312-62571-9. Dr. Forni also wrote “Choosing Civility” and “The Civility Solution”.

    May 25, 2014

  • Technology helps with learning, but take care

    Since I have been involved in teaching, two different technologies have been applied to learning at the secondary and collegiate level. The first was video (from videocassettes to DVDs) where a student or class might watch a presentation of some historical event, or a set of scientific principles or even a simulated exploration of the human body.

    May 18, 2014

  • Here are numbers that apply in our lives

    One of the best exercises is walking. Cardiologists suggest that each of us walk 10,000 steps per day. Assume each step is 0.5 meters or 19.7 inches. Then 10,000 steps would cover 5,000 meters or 3.11 miles. But studies find that the average American (from age 4 and up) takes only 2,000 steps/day or 1 kilometer.

    May 11, 2014

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