The Amazing Heart
By Chun-Wai Chan, M.D.
The Amazing Function
A beating heart signifies life. The main mission of the heart is to keep the body’s circulatory system going. Transporting blood to 60,000 miles of blood vessels, it delivers oxygen from the lungs, nutrients from the gastrointestinal tract, hormones from endocrine glands, as well as other substances to the cells. It carries waste products from the cells to the liver or kidneys to be broken down or excreted outside the body. In addition, the circulating blood maintains body temperature, acid-base balance, and readiness for deployment of the immune system. All this is essential for cells to survive.
The main driving force of the body’s transport system is the heart. It beats about 80,000 to 100,000 times a day, transporting about 2,000 gallons (7,600 liters) of blood via the blood vessels. The heart of an 80-year-old person, for example, would have transported approximately 50 billion gallons (190 billion liters) of blood in his or her lifetime! Despite such a large load, the heart works continuously on its own without resting or closing for maintenance. No manufactured machine can come close to such performance and durability! The survival of every organ depends on the heart. When the heart stops pumping, the entire body shuts down. Without oxygen, all the organs stop functioning, and within half an hour, the cells begin to die.
The Amazing Formation
The way the heart and blood vessels are formed is truly amazing! New life starts when a sperm meets an egg, forming a zygote. Immediately, successive cell divisions begin with one cell becoming two, two becoming four, and four becoming eight, etc. This cluster of cells forms the primitive embryo. Within three weeks of conception, the primitive embryo has three primary cell layers: the ectoderm (outer layer), mesoderm (middle layer), and endoderm (inner layer). In general, cells in the outer layer develop into the nervous system, eyes, inner ears, skin, and connective tissues. Those in the middle layer develop into the circulatory system, skeleton, muscle, and kidneys, and those in the inner layer, the respiratory system, digestive system, bladder, etc. These cells differentiate in a predictable and orderly fashion, as if they receive certain instructions to do so. The way each cell from the same layer is pre-destined to develop into distinctive tissues and organs is a mystery for scientists.
The writer of Ecclesiastes reminds us: “He (God) has made everything beautiful in its time. He has also set eternity in the hearts of men, yet they cannot fathom what God has done from beginning to end” (3:11).
The circulatory system, which develops from the mesoderm, the middle layer, is the first system formed, and the heart is the first organ formed in the baby. Within three months of conception, the fetal heart is fully functional, just like the heart of a newborn. Meanwhile, the blood vessels continue to grow and become arteries and veins for various parts of the fetus, completing the initial development of the circulatory system.
The Amazing Design
The driving force of the heart comes from the heart muscles. The key to the heart’s powerful contractile force is its unique structural composition providing excellent mechanical advantages. Scientific research about the heart has led to two conclusions: 1) There is still a lot we do not understand about the heart; and 2) We must admit that both the heart, muscles, blood vessels, and nerves are perfectly designed to give the heart incredible functions and durability.
Every part of the body—not just the heart—is wonderfully made! Nothing is randomly made. God the Creator has wonderfully designed the human body. As King David of Israel once proclaimed: “For you created my inmost being. You knit me together in my mother’s womb. I praise you because I am fearfully and wonderfully made. Your works are wonderful; I know that full well” (Psalm 139:13–14).
In His designing of the human body, our wonderful God created both male and female. The genetic codes are passed on from generation to generation through marriage and reproduction. Sadly, throughout human history, people rarely ponder or show appreciation for the mysteries of His creation. Instead of glorifying God and praising His name, they refuse to acknowledge the existence of an infinite God. As in Adam and Eve’s rebellion against God, they pass on the sinful nature to future generations, with thoughts and deeds which contradict God’s holiness.
The Bible teaches that we all have sinned, and the consequence of sin is death. But our loving God sent His son Jesus Christ to this world, born of the virgin Mary, to die on the cross to redeem us from our sins. He arose from death on the third day and promises us: “I am the resurrection and the life. Whoever believes in me will live, even though they die; and whoever lives by believing in me will never die” (John 11:25–26). If we believe in Him, confess our sins and repent, He will redeem us, accept us as His children, and grant us eternal life. This is one of God’s mysteries that is beyond our comprehension. And it is the source of true blessings.