We occasionally hear the accusation “their god is their stomach.” It scarcely needs pointing out, however, that the god of gastroenterology cannot compete with the God of eternity. “God designed the human machine to run on Himself,” explains C. S. Lewis. “He Himself is the fuel our spirits were designed to burn, or the food our spirits were designed to feed on. There is no other. That is why it is just no good asking God to make us happy in our own way without bothering about religion. God cannot give us a happiness and peace apart from Himself, because it is not there. There is no such thing.”19
When the disciples encouraged Jesus to eat, He replied: “I have food to eat that you know nothing about. … My food … is to do the will of him who sent me.”20
Musculoskeletal System
The adult human has 206 bones, a number 40 percent decreased since infancy due to the fusion of adjacent bones. Bones are a composition of mineral crystals (mostly calcium and phosphorus), collagen, and cells. The resultant material is as strong as granite in compression and twenty-five times stronger than granite under tension.21
People are routinely shocked to discover the pressure bones must withstand. Considering the twenty-six bones in each foot, orthopedist Dr. Brand observes that “a soccer player subjects these small bones to a cumulative force of over one thousand tons per foot over the course of a match.”22 The femur is stronger than reinforced concrete and must bear an average of 1,200 pounds of pressure per square inch with every step. The mid-shaft of the femur is capable of supporting a force of six tons before it fractures.23
Why are humans six feet tall and not sixty? For one reason, if we were sixty feet tall we would fracture our femur with every step—which would make going to get the mail feel like a rugby match. It is all a matter of geometry and gravity.24 God no doubt had the math worked out with the original blueprint, and I’m glad He didn’t misplace a decimal point.
Of interest (although of surprisingly little relevance to our skeletal system), the weight of the atmosphere pressing down on our shoulders is one ton. If it feels at times that we are supporting a huge load in life, we are. Yet it is not our bones that bear this burden, but instead the support of equal air pressure on all sides. Despite this scientific brush-off of atmospheric tonnage, in another sense we do indeed labor under another enormous weight—namely our own collective fallenness. What will it feel like, on the other side of eternity, to have this exhausting and painful daily weight removed?
Bone is living tissue with a vibrant blood and nerve supply. Yet by volume, only 2 percent of bone is made up of cells. These cells are capable of destroying old bone structure (the osteoclasts) and rebuilding new bone (the osteoblasts). Our skeleton, on average, replaces itself totally about every seven years.
After damage to the bone, osteoclasts are recruited to the site of injury where they resorb the impaired bone material. When their job is finished, the osteoclasts undergo programmed cell death. Next, osteoblasts are recruited to the site. They make layers of osteoid that slowly refills the cavity. When the osteoid reaches six microns thick (two ten-thousandths of an inch), it begins to mineralize. Even after the cavity has been filled with bone, still for months the crystals of mineral are packed more closely and the new bone density continues to increase.25 When the process is complete, the bone will be as strong as before the original injury.
Of the two to four pounds of calcium in the body, nearly 99 percent is in the bones and teeth. The remaining 1 percent, however, is of critical importance in blood clotting, nerve transmission, muscle contraction, and heart function. The body keeps the blood level of calcium within a narrow range, and if needed, the bone releases it readily.26 This is made possible by the exceptionally large total surface area of the tiny mineral crystals within the bone, equal to one hundred acres! Each of the small crystalline surfaces is exposed to a watery solution that permits the ready exchange of chemicals on demand.27
The core of many bones contains marrow, a remarkable blood cell factory that turns out a trillion cells daily. It produces red blood cells (with a life span of 120 days), platelets (with a life span of 6 days), and white blood cells (with a life span of 1 day or less). If blood loss occurs in the body, the marrow can dramatically increase the RBCs and platelets according to need. If infection threatens, the WBC numbers surge. Cells of the immune system also are initially derived from the bone marrow. In addition, the marrow contains a small number of invaluable stem cells that assure the continuation of future generations of marrow cells.
Where one bone is joined with another, the connecting tissue is called a ligament. Where a bone is joined to a muscle, the connecting tissue is called a tendon. The body’s 200 bones and 600 muscles work together as integrated units, often hinged by joints. Just lifting a forkful of food from the plate to the mouth involves the use of more than thirty joints. If our spiritual sensitivity were sufficiently alert, the eye-brain-nerve-bone-joint-muscle coordination permitting such a movement would consistently inspire awe each time it was successfully completed.
The mechanism regulating muscle function is extraordinarily complex and still, after all these years, not completely understood. Perhaps we can agree together to skip the details (of myofibrils, filaments, sarcolemma, sarcoplasm, sarcoplasmic reticulum, A bands, I bands, H zone, Z line, actin, myosin, tropomyosin, troponin, myoglobin, ADP, ATP, creatine phosphate, pyruvic acid, lactic acid, membrane potential, myoneural junction, and motor end plates) and instead simply point out that the facial muscles are capable of seven thousand movements, that striated muscle can contract in one-tenth of a second, that jaw muscles can exert 200 pounds of pressure, and that the total tension that could be developed by all the muscles in the body of an adult man is nearly twenty-five tons.
Compare this to the best bionic efforts of engineers. In 1999, for example, NASA built the first artificial muscles and staged the world’s first myo-bionic handshake. But the resultant “grip,” generated by four polymer strips designed to bend in response to electrical charges, was barely noticeable.28 God, with a twinkle in His eye, watched in amusement.
Additional Evidence of God’s Genius
Everywhere we look in the human design we find displays of God’s precision. No tissue, no organ system is so simplistic that it fails to elicit awe. And still we have not exhausted all the evidence available for us to uncover.
Each kidney has over one million nephrons, with each nephron being a complete urine-forming unit. The renal system receives 1,800 quarts of blood a day. In the glomeruli and tubules, the blood undergoes a sophisticated process of filtration and reabsorption. The glomeruli produce 190 quarts of filtrate daily, which is then passed on down the line to the tubules. In the tubules, 99 percent of the water (along with important chemicals and electrolytes) is reabsorbed. The final result is 11/2 quarts of urine, thus removing from the body toxins and harmful byproducts of metabolism.
The kidneys play an important role in fluid conservation. Approximately 60 percent of our body is made up of water . The brain, for example, is 70 percent water, the skeletal muscle 75 percent, and the lung tissue nearly 90 percent. If we lose even as much as 3 percent of our total body water, the resultant dehydration causes both fatigue and dysfunction. The loss of 10 percent threatens life.
How did God do so much with plain water? It is not that He uses exotic ingredients to construct the body—in fact, He uses common materials. His secret lay in the brilliant use of design. To the non-integrationist, our body is three-fourths water and fat. To the theistic integrationist, however, we are much more. When we factor in the spark of the divine, the picture comes into focus. Instead of semi-organized piles of random fat and water, we are “fearfully and wonderfully made.”29 Even in his suffering Job understood: “Your hands shaped me and made me. … You gave me life and showed me kindness, and in your providence watched over my spirit.”30
The ovaries contain two million primordial eggs, all formed before birth. Only about 400 of these will develop into maturity,
one per month. The all-time record for childbirth was set by a Russian woman who produced sixty-nine children between the years 1725 and 1765.31 There is reason to suspect it is one record that might yet stand for another 250 years.
The sperm, in contrast to the pre-formed egg cells, are produced each day—120 million of them. Formed in the testicles, they are then stored in the redundant twenty-foot-long epididymis. An ejaculate can contain 200 to 400 million sperm. Of these, a few hundred thousand will reach the uterus; a thousand or so will reach the Fallopian tube; and about a hundred survive to reach the targeted egg cell.32
Once the winning sperm hits the egg cell, rapid chemical changes occur in the egg that preclude any other sperm from entering. At that point the DNA in the egg and sperm merge, finally settling on one unique individual configuration among tens of millions of genetic possibilities. Thus begins the miraculous construction of yet one more Image bearer.
We know from Christ’s example that God is partial to little children. Is He perhaps then present in these early DNA details, at the exact moment of conception? I rather think so. “You knit me together in my mother’s womb,” said David.33 Perhaps it is all simply too exciting for Him to stay away.
Our BODY, His TEMPLE
EVERY human body is a miracle exceeding comprehension. The complexity and dimensions involved are staggering to the mind, straining our abilities to apprehend the grandeur. Yet if we make the effort to reach for the meaning behind the biology, we will find ourselves edified on several levels.
First, we will see anew the power and precision of God. When we think of the majesty of God, we don’t have to look through a telescope to the distant recesses of the universe—we need only look in the nearest mirror. If we doubt His abilities to help us with the intricacies of our day-to-day problems, we ought doubt no more. No human dilemma, no matter how convoluted or refractory, can begin to challenge God’s demonstrated mastery of detail as seen in the previous chapters.
Second, we will be increasingly aware of the intimacy with which He carries out His creative efforts. This is a hands-on God, both in the creating and sustaining phases. He has not drifted off to sleep, nor is He preoccupied with some difficult problem on the other side of the universe. In fact, He watches over us more intimately than the human mind has the ability to perceive. Think of the red blood cell shed from the cross that had your name on it. Take a deep breath, and remember that you just inhaled 150 million air molecules that Jesus Himself breathed. Christ has a closeness and a familiarity with those for whom He died as He breathes new life into anyone willing to receive it.
Third, we will benefit from the reminder that God has a triple claim on us: as creator, redeemer, and sustainer. In light of such a claim we relinquish our bodies back, yielding to the One who cares more for us than we do for ourselves. In this yielding we find not defeat, but an unexpected freedom. May our surrender be a glad surrender.
God’s Human Body Project
It is perhaps beneficial to collect the most impressive of God’s human body accomplishments in one place and regard them all together. As we review, I might suggest that we develop a cumulative impression of what this picture reveals about the genius, power, sophistication, and artistry of God.
The human body is composed of ten thousand trillion trillion atoms—a number greater than the stars in the universe. In each person, more than a trillion of these atoms are replaced every one-millionth of a second.
These atoms, in turn, are comprised of subatomic particles, some of which have a life span of less than a billion billionth of a second. It is entirely possible that we have no subatomic bottom. As the technology becomes increasingly sophisticated, we discover yet smaller particles. We are, perhaps, infinite in the subatomic direction.
Each human cell is made up of a trillion atoms. The body contains between 10 and 100 trillion cells. We tear down and rebuild over a trillion cells every day. Each cell is remarkable in its own miniaturized way, with electric fields, protein factories, and hundreds of ATP energy motors 200 thousand times smaller than a pinhead.
In a lifetime, the heart beats over two billion times and pumps sixty million gallons of blood through sixty thousand miles of blood vessels. The smallest capillary vessels have seventy thousand square feet of surface area, a delicate wall several thousand times more fragile than toilet tissue. We each manufacture over two million red blood cells every second. Laid side by side, our red blood cells would stretch 100 thousand miles.
We breathe 600 million times over an average life span, with every breath containing over a billion trillion air molecules. These air molecules enter 300 million alveoli that provide a total surface area half the size of a tennis court. The hemoglobin in each red blood cell can carry a million molecules of oxygen to the cells.
The retina of the eye contains over 100 million rods and cones that take continuous pictures under light conditions that can vary by a factor of ten billion. Individual retinal photoelectric cells are so sensitive that they can be triggered by one billion-billionth the amount of light emitted by a flashlight. In one-third of a second, the retina solves the equivalent of nonlinear differential equations that would take a supercomputer 100 years to solve.
The ear has a million moving parts, can vibrate twenty thousand times per second, can hear sounds over a range of intensity that varies by a trillion, and can distinguish among two thousand different pitches. Sound waves that move the eardrum less than the diameter of a hydrogen molecule can be perceived by the brain, with the faintest sound audible having the negligible pressure of one ten-thousandth the push of a healthy mosquito. The ear can gauge the direction of a sound’s origin based on a 0.00003 second difference in its arrival from one ear to the other, and it has a sophisticated balance mechanism containing 100 thousand hair cells.
The human nose can distinguish ten thousand different smells, including some chemicals present in only 1 part to 400 million parts air. We have nine thousand taste buds in our mouths and over 400 touch cells per square inch of skin. We can “feel” a pressure on our face that depresses the skin 0.00004 inch.
Our three-pound brain is the most complex arrangement of matter ever discovered in the universe. It contains ten billion neurons (possibly ten times as many) and has 100 trillion neurological interconnections that if stretched out would extend 100 thousand miles. The brain fires at a rate of a thousand trillion computations per second and can hold information equivalent to that contained in twenty-five million books. From Einstein to savants, we are known for prodigious feats of memory. Each of us carries around a mental videotape cassette containing three trillion pictures. We are the only species with the gift of language, are capable of thinking at a rate of 800 words per minute, and have use and recognition vocabularies of ten thousand and forty thousand words, respectively.
Billions of skin cells are replaced every day and the entire epidermis is replaced every couple of weeks. We each have five million hair follicles on our bodies and, in a lifetime, grow over two million feet of hair on our scalp.
Our twenty-two feet of small intestine has an absorptive surface area equal to that of a tennis court and is equipped with a “second brain.” As an energy extractor, the digestive tract is 95 percent efficient. The liver has 300 billion cells that perform over 500 functions and can almost completely regrow itself if needed.
The adult human has over 200 bones that are as strong as granite in compression and twenty-five times stronger under tension. The femur is stronger than reinforced concrete, must bear an average of 1,200 pounds of pressure per square inch with every step, and is capable of supporting a force of six tons before it fractures. A soccer player bears a cumulative force exceeding one thousand tons per foot over the course of a match.
Our skeleton replaces itself totally about every seven years, contains a marrow that produces a trillion blood cells daily, and has a mineral crystal surface area of 100 acres, thus allowing for the quick exchange of calcium and other minerals as needed. We
have over 600 muscles, including facial muscles capable of seven thousand movements. The total tension that can be developed by all the muscles of an adult man is nearly twenty-five tons.
Each kidney has over one million nephrons, and the renal system processes 1,800 quarts of blood a day. The female ovaries contain two million primordial eggs, all formed before birth. Only about 400 of these will develop into maturity. In contrast, the male produces over 100 million sperm each day, which are stored in the redundant twenty-foot-long epididymis. When the egg and sperm meet, the DNA must settle on one unique individual configuration among tens of millions of genetic possibilities.
The nucleus of this initial fertilized egg contains DNA-based chromosomes with 100 thousand genes and three billion base pairs. This initial single-cell DNA is over five feet long but only fifty-trillionths of an inch wide, weighing 0.2 millionth of a millionth of an ounce. The DNA from all the cells in one human body would stretch over ten billion miles.
From Dust to Honor
The biology involved is obviously stunning. What about the theology? Scripture teaches that we are made in God’s very image, in His likeness.1 We are made a little lower than the angels and crowned with glory and honor.2
God knows us even before He first forms our frame. He realizes that we are “dust,” and knows that we are frail. He knows every word before it is on our tongue. He knows the thoughts of our mind and the intents of our heart. As it turns out, we were not just some science project for a rainy day in Heaven, but instead a creative effort treasured by the Father. He made us for His glory and His pleasure.
When we gain a picture of what this creative God has done within us, it helps us to understand that we are more than a random collection of organized atoms. Within the miracle of the human body, there is sanctity, hope, and glory. More important, this same awareness also helps us to appreciate that such a Creator is rightly regarded with awe.
More Than Meets the Eye Page 9
