The miracle of life is a process of human reproduction. Four and half billion years ago the young plant earth was a mass of cosmic dust and particles. It was almost completely engulfed by the shallow primordial seas. Powerful winds gathered random molecules form the atmosphere. Some were deposited in the seas, tides and currents swept the molecules together, and somewhere in this ancient ocean the miracle of life began. The first organism of primitive life was the protozoa. Millions of protozoa populated the ancient seas. These early organisms were completely self-sufficient. They moved about their aquatic environment feeding on bacteria and other organisms. They are covered with a hundred little hairs called cilia. From these one cell organism evolved all life on earth and the foundation of life, the cell. The cell has endured unchanged since the first time the organisms swam in the cradle of life, the sea. Every living being is made up of cells, the basic units of life on earth. All cells reproduce themselves by dividing themselves into two identical cells. There now becomes two cells exactly like the parent. In the cell’s nucleus is a strong substance known as DNA. The DNA is contained in forty-six chromosomes in every cell of the human body. Each chromosome is in turn made up of thousands of genes, discrete segments of DNA which lie along the chromosome. Penetrating even deeper into the structure of the chromosome there are DNA molecules themselves. The DNA contains all the genetic information of the cell. DNA is the only living substance capable of reproducing itself exactly. Without DNA duplication and therefore life itself is not possible. All DNA and all living organisms are chemically identically but its arrangement in genes and chromosomes determine what the cell will become. For example tiny primitive organism, the protozoa to the massive complex mammal like the elephant, a palm tree swaying in the breeze, or even a human being. The actual conception and growth of a new human being is a wondrous and complex process. Each beginning lies deep inside the mother’s body called the ovaries. Each ovary contains a quarter of a million egg cells which reach full development even before the woman herself was born. The eggs each contain twenty-three chromosomes, the mother’s genetic contribution to her future offspring. During each menstrual cycle, the ovaries produce hormones which stimulate the growth of a single one of the eggs. At the midpoint of her cycle, the follicle which encloses the egg in its protective layers ruptures. This is ovulation, the egg travels through the fallopian tube which connects the ovary and the uterus or womb. In the tube the egg waits for sperm form the father to fertilize it. The fertilized egg now with genetic material from both the parents’ moves through the tube where it attaches itself to the nutrient rich lining. Here the ovary itself becomes mature and it becomes surrounded by its nutritive layers. When it is fully developed the follicle which encloses the egg will swell with liquid fluid. Inside the follicle the egg and its nutritive layers floats in the water of life which has the same salt content as the sea. The swollen follicle is then gently brushed by the swaying outer most fridges of the fallopian tube. These fringes are activated by the hormones just before ovulation. They sweep over the seas of the ovary looking for the newly released egg. As ovulation nears the fringes become filled with blood. The follicle bursts and the liquid fluid pours out of the follicle concealed somewhere within it is the egg. The fringes search for the newly released egg and it lies surrounded by a cloud of its own nutritive cells. It is only the size of a grain of sand. The egg is drawn into the fallopian tube; deep inside the egg is the nucleus of new life itself. The mouth of the fallopian tube and its imperceptible muscle contractions move the egg along towards the uterus. The egg then reaches the interior of the tube itself, these many fold of tissue are lined with tiny cilia which maintain a constant gentle motion that draws the egg along its length. The inside of the tube is actually only the thickness of a human hair. It takes the eggs three to four days just to travel five inches. The translucent egg lies deep in the muscle fold in the fallopian tube. The cilia lines the tube gently moving the egg along they are exactly just like cilia of the primitive protozoa. The egg and the sperm must join together within twenty-four hours of leaving the ovary for conception to take place. If no sperm are present the egg disintegrates and the same cycle continues the following month and the same cycle will continue throughout the woman’s child bearing years. This remarkable cycle is made possible by complex molecules; the sex hormones. Hormones control a women’s entire reproductive cycle. Hormones control a men’s reproductive ability as well. Only seven weeks after conception the fetal system is permanently synthesized to the male or female by the sex hormones. One fetus will develop ovaries and its brain will be programmed to release hormones in cycles, it is female. Another fetus will develop testicles and its brain will programmed to release constant levels of sex hormones. Seventy-seven million human beings have lived on this planet and every year one hundred and twenty-eight million are born. After having talked about the females reproductive and genetic contributions I will now talk about the man’s reproductive and genetic contribution. During a man’s life time the testicles produce billions of sperm. The prostate gland releases an alkaline fluid to protect the sperm. During ejaculation the sperm goes through a tube in the body cavity and as they approach the vesicles the prostate gland releases the fluid in combination with the sperm. The blended semen then continues out of the man’s body through the urethra in the penis. During sexual arousal the valve in the bladder stops urine form entering the urethra. Near the bladder the urethra passes through the prostate gland. The walls of the prostate squeeze out prostate fluid when sperm passes through the urethra, it is about a size of a gulf ball but acts as a sponge. Inside it is filled with a small cavity that produces the fluid. Unlike the ovaries in the female counterpart the testicles lie outside of the body cavity. The testicles are made up of tightly coiled tubules which have a total length of seven hundred feet. In the tubules, sperm is produced at an extraordinary rate of one million every twenty four hours. In the tissue between the tubules, the sex hormone testosterone is produced. The testicles are the essential male organs of reproduction. They function well only under very specific conditions. One of these specific conditions is temperature. Sperm is produced below normal body temperature. The scrotum keeps the testicles away from the body’s heat. At the center of the tubule lies the transport canal which carries mature sperm away for storage. Smaller compartments produce many new immature sperm every thirty-six hours. When they become more mature they move closer to the center of the canal. The average man produces over four hundred billion sperm in his life time. They are tightly packed within the tubule. Their hands and tails intertwine. Inside the developing sperm heads the normal body cells forty-sixty chromosomes have been reduced to twenty-three chromosomes but this reduction of chromosomes is so essential to the future of reproduction of species puts the sperm in more danger. The sperm are defended by the nurse cell. They form special protective barriers around the mature sperm cells. Each nurse cell cares for many sperm cells at a time. The nurse cells are connected to one hundred and fifty cells through the tendrils. The tendrils enable the nurse cells to feed and protect the maturing sperm cell and to move them closer to the transport canal. During its development it lays in passivity and protected by the nurse cell. When mature it is transported by the nurse cell to the transport canal. Millions of sperm are densely packed in these tubules which if stretched out are fifteen to twenty feet long. The mature sperm will pass out of the man’s body through ejaculation or they will eventually die and will be reabsorbed. These sperm carry the man’s genetic material and are fully mature but not yet they are not yet able to fertilize a woman’s egg. They do not attain that ability until they are up inside the woman’s body. The sperm during this time they develop the ability to swim. A sperm propels itself through means of a tail known as the flagella which lashes vigorously from side to side. This single activity has only one purpose and that is to deliver the genetic material from the sperms head quickly and preciously to the woman’s egg. On the tip of the sperm’s head are layers of enzymes, and enzyme inhibitors. The enzyme inhibitors will be saved for later as they are about to penetrate the woman’s egg. The propulsion of the sperm is actually made up of tiny thin strands of filaments. About twenty percent of the man’s sperm is deformed or imperfect. One reason man produces so many sperm is because so many things can go wrong with the sperm. Some have two or three tails, some are attacked by bacteria, and some have tails that are detached from the head. Most of the deformities can occur from a slight change in temperature of the testicles. Overcrowding, stress, smoking, chemical population of air and water, occupational hazards, radiation, and poor nutrition are all part of modern life. Even modern clothing may affect sperm production, for example, tight blue jeans may hold the testicles up closer to the body which can raise the temperature those few critical degrees which can affect sperm.
Despite these obstacles human beings have been successfully reproducing for many millions of years. Since the first organisms swam in the sea, the cycle of life has been continuous fueled by the need and the drive to reproduce. Among human beings that drive is intimately linked with attraction and desire. Affection and romantic love may initiate the dance of courtship which may lead to conception. Sexuality, affection, and tenderness are all the complex rituals of mating but desire and physical love posses a silent language on their own that signal partners’ readiness to each other. The eyes are part of that silent language; visual impressions stimulate and excite special nerve cells in the sexual areas throughout the body. The skin is also part of that silent language it is extremely sensitive and responsive to the touch. It contains millions of sensory receptors which when stimulated direct messages of sexual arousal to the brain. Many of these are concentrated in the bodies most responsive zones known as the erogenous areas. The man’s penis is densely packed with sensory receptors. They relay messages of sexual stimulation to the brain which triggers the sequence of complex events leading up to ejaculation. The length of the penis is made up of many small cavities known as erectile tissue. When a man is sexual aroused the signals from the brain cause these erectile tissues to be gorged with blood. The sudden flow of blood in the penis raises its temperature. The man’s blood pressure, heart beat, and respiration increase and the blood causes the man’s penis to be erect and fully elongated so sperm can be easily delivered to the woman’s egg. As sexual arousal reaches its peak the entire male system must function properly for ejaculation to take place. As semen enters the woman’s body it immediately slows down. The environment in the vagina is extremely acidic it protects the woman from bacteria and infections but it is extremely inhospitable. Nearly one quarter of the sperm will die immediately. The surviving sperm become extremely active and begin to rapidly swim upwards towards the downward current. The sperm’s activity has one goal and that is to find and fertilize the egg. The sperm release their digestive enzymes to be able to reach the egg but in the end only one will be able to fertilize the egg. As soon as one sperm fertilizes the egg, the egg then becomes impermeable and rejects all other sperm. The genetic material of the mother’s egg and the father’s sperm combine. When cell division is in the form of mitosis it is usually associated with cell growth, nourishment, and reproduction. The process of human reproduction involves the duplication of the DNA and the splitting of the nucleus. Mitosis is a type of cell division that produces two genetically identical cells from a single cell. Mitosis is basically a process that a cell goes through to form two new nuclei, with each nuclei containing the same number of chromosomes. Mitosis is used by many unicellular eukaryotic organisms for reproduction. Multicellular organisms use mitosis for growth, nourishment, and reproduction. It is when two cells have joined to form a new cell and within twenty-four hours the cell begins to divide. Once the cell begins to divide it is known as a zygote. As the zygote divides it moves towards the uterus. Within ten days of fertilization the zygote firmly implants itself in the lining of the uterus. The coming of the two parent cells give rise to a unicellular zygote, through cellular division and cell growth, this process is completed to perfection every time with every rarely a mistake or imperfection. Although embryonic development takes approximately nine months, the greatest amount of cellular growth takes place during the first several weeks of pregnancy. This period is known as embryogenesis. After two weeks the embryo is elongated. At the top is what will become the head and at the bottom is a tail that will nourish it. At four weeks the embryo has arm buds and is distinctly curved, it also has the beginning of eyes. At five weeks the nose takes shape and at six weeks the leg buds are apparent. At seven weeks the embryo has clearly defined hands and can move them. At week eight the organs begin to be visible and the eye lenses are formed. At ten weeks the embryo is considered a fetus and still has a tail. At thirteen weeks it develops an umbilical cord and is three inches long. By fourteen weeks it can bring its hands together. The umbilical cord is the source of nutrient and air supply. They always say the greatest miracle in life is life itself and this holds true as reproduction is the driving force of growth so it is after nine months a beautiful child is born and this is the miracle of life.
In conclusion, the cell has endured unchanged since the first time the organisms swam in the cradle of life, the sea. Every living being is made up of cells, the basic units of life on earth. All cells reproduce themselves by dividing themselves into two identical cells. There now becomes two cells exactly like the parent. In the cell’s nucleus is a strong substance known as DNA. The DNA is contained in forty-six chromosomes in every cell of the human body. Each chromosome is in turn made up of thousands of genes, discrete segments of DNA which lie along the chromosome. Penetrating even deeper into the structure of the chromosome there are DNA molecules themselves. The DNA contains all the genetic information of the cell. DNA is the only living substance capable of reproducing itself exactly. Without DNA duplication and therefore life itself is not possible. All DNA and all living organisms are chemically identically but its arrangement in genes and chromosomes determine what the cell will become and this is the miracle of life.
Despite these obstacles human beings have been successfully reproducing for many millions of years. Since the first organisms swam in the sea, the cycle of life has been continuous fueled by the need and the drive to reproduce. Among human beings that drive is intimately linked with attraction and desire. Affection and romantic love may initiate the dance of courtship which may lead to conception. Sexuality, affection, and tenderness are all the complex rituals of mating but desire and physical love posses a silent language on their own that signal partners’ readiness to each other. The eyes are part of that silent language; visual impressions stimulate and excite special nerve cells in the sexual areas throughout the body. The skin is also part of that silent language it is extremely sensitive and responsive to the touch. It contains millions of sensory receptors which when stimulated direct messages of sexual arousal to the brain. Many of these are concentrated in the bodies most responsive zones known as the erogenous areas. The man’s penis is densely packed with sensory receptors. They relay messages of sexual stimulation to the brain which triggers the sequence of complex events leading up to ejaculation. The length of the penis is made up of many small cavities known as erectile tissue. When a man is sexual aroused the signals from the brain cause these erectile tissues to be gorged with blood. The sudden flow of blood in the penis raises its temperature. The man’s blood pressure, heart beat, and respiration increase and the blood causes the man’s penis to be erect and fully elongated so sperm can be easily delivered to the woman’s egg. As sexual arousal reaches its peak the entire male system must function properly for ejaculation to take place. As semen enters the woman’s body it immediately slows down. The environment in the vagina is extremely acidic it protects the woman from bacteria and infections but it is extremely inhospitable. Nearly one quarter of the sperm will die immediately. The surviving sperm become extremely active and begin to rapidly swim upwards towards the downward current. The sperm’s activity has one goal and that is to find and fertilize the egg. The sperm release their digestive enzymes to be able to reach the egg but in the end only one will be able to fertilize the egg. As soon as one sperm fertilizes the egg, the egg then becomes impermeable and rejects all other sperm. The genetic material of the mother’s egg and the father’s sperm combine. When cell division is in the form of mitosis it is usually associated with cell growth, nourishment, and reproduction. The process of human reproduction involves the duplication of the DNA and the splitting of the nucleus. Mitosis is a type of cell division that produces two genetically identical cells from a single cell. Mitosis is basically a process that a cell goes through to form two new nuclei, with each nuclei containing the same number of chromosomes. Mitosis is used by many unicellular eukaryotic organisms for reproduction. Multicellular organisms use mitosis for growth, nourishment, and reproduction. It is when two cells have joined to form a new cell and within twenty-four hours the cell begins to divide. Once the cell begins to divide it is known as a zygote. As the zygote divides it moves towards the uterus. Within ten days of fertilization the zygote firmly implants itself in the lining of the uterus. The coming of the two parent cells give rise to a unicellular zygote, through cellular division and cell growth, this process is completed to perfection every time with every rarely a mistake or imperfection. Although embryonic development takes approximately nine months, the greatest amount of cellular growth takes place during the first several weeks of pregnancy. This period is known as embryogenesis. After two weeks the embryo is elongated. At the top is what will become the head and at the bottom is a tail that will nourish it. At four weeks the embryo has arm buds and is distinctly curved, it also has the beginning of eyes. At five weeks the nose takes shape and at six weeks the leg buds are apparent. At seven weeks the embryo has clearly defined hands and can move them. At week eight the organs begin to be visible and the eye lenses are formed. At ten weeks the embryo is considered a fetus and still has a tail. At thirteen weeks it develops an umbilical cord and is three inches long. By fourteen weeks it can bring its hands together. The umbilical cord is the source of nutrient and air supply. They always say the greatest miracle in life is life itself and this holds true as reproduction is the driving force of growth so it is after nine months a beautiful child is born and this is the miracle of life.
In conclusion, the cell has endured unchanged since the first time the organisms swam in the cradle of life, the sea. Every living being is made up of cells, the basic units of life on earth. All cells reproduce themselves by dividing themselves into two identical cells. There now becomes two cells exactly like the parent. In the cell’s nucleus is a strong substance known as DNA. The DNA is contained in forty-six chromosomes in every cell of the human body. Each chromosome is in turn made up of thousands of genes, discrete segments of DNA which lie along the chromosome. Penetrating even deeper into the structure of the chromosome there are DNA molecules themselves. The DNA contains all the genetic information of the cell. DNA is the only living substance capable of reproducing itself exactly. Without DNA duplication and therefore life itself is not possible. All DNA and all living organisms are chemically identically but its arrangement in genes and chromosomes determine what the cell will become and this is the miracle of life.
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