Paging Dr. Frischer – The Human Body

Let’s take some time to appreciate the incredible things our body does every second of every day…without needing any conscious direction.  The human body is an amazingly complex and intricate system, one that is still capable of baffling doctors and researchers, despite thousands of years of study.  It is truly fascinating. Take our red blood cells:

· About 2 ½ million are produced every second by our bone marrow, and then added to the blood stream.  That’s about equal to the population of Denver.  (When we account for all new cell production including red blood cells, our bodies manufacture about 25 million every second. That’s the entire population of Los Angeles…twice!)

·Red blood cells travel a very long distance each day…about 12,000 miles.

·There are approximately 2 ½ trillion red blood cells in our body at any given time, and each lives for about 120 days.

And when is the last time you ordered your heart to beat?

·Without our conscious control, it beats around 100,000 times every day, or about 36 million times per year.  In a lifetime that could be about 2 3/4 billion times.

·Our heart muscles create enough pressure to squirt blood 30 feet.  No wonder we can feel our heartbeat, and locate our pulse, so easily. What manmade machine works that well?

·The artery into which the heart pumps blood is the aorta.  Its diameter is almost that of a garden hose, even though the average adult heart is only about the size of two fists.  This artery needs to be so large because it is the main supplier of rich, oxygenated blood to the rest of the body.

Let’s move up to our brain.  It is easily the most complex and least understood organ in the body.

·Ever wonder how our reaction time can be so fast?  Nerve impulses travel to and from the brain at up to 170 miles per hour.

·The human brain can hold five times as much information as an old-fashioned encyclopedia set. It’s capacity has been estimated at anywhere from 3 to 1,000 terabytes of data.

·Our brain makes up about 2% of our body mass, yet uses 20% of the oxygen that enters the blood stream – more by far than any other organ.

·Our brain is much more active at night than during the day.  Scientists are not sure why, but when we shut down our conscious mind, our brain gets going.

·The higher our IQ, the more we dream.  On the other hand, some people have trouble recalling their dreams, and that is not a sign of low intelligence.  Sometimes our dreams seem to go on and on, but the average length of a dream is only two to three seconds.

·Eighty percent of the brain is made up of water.  While it looks like a firm, gray mass, it is actually squishy, pink, and full of blood and water.

·The brain doesn’t feel pain.  In fact, patients undergoing brain surgery are sometimes kept awake in order to give feedback to the surgeon.  Note that headaches are not due to pain from brain tissue, but rather from nerves, tissues and blood vessels surrounding the brain.

·Neurons continue to grow until we die.  Let’s use this as a reminder to continue to learn as we age.

Yes, our bodies are pretty impressive.  Let’s continue to explore fascinating facts about our bodies in my next column.

Dr. Alan Frischer is former chief of staff and former chief of medicine at Downey Regional Medical Center. Write to him in care of this newspaper at 8301 E. Florence Ave., Suite 100, Downey, CA 90240.

 

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Published: July 24, 2014 - Volume 13 - Issue 15

Jennifer DeKay