From Fertilization to Birth, Term Paper Example
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Undoubtedly having a baby is the most exhilarating and joyous experience in the woman life. Giving a baby birth is not a simple task for a hopeful mother; most of the women during baby birth go through a painful labour, and they put a number of efforts just to be capable of baby delivery. In this stage of life, a hoping mother must have better understanding of all this process do that the emotionally, physically, and financially complications can be avoided.
All human beings start life from a single cell that is formed when the sperm of father fertilizes the egg of mother. Normally, the fertilization occurs in the Fallopian tube of mother, which links the womb (uterus) with the ovary. The uterus is considered the shape and size of a large pear: it is made with the muscle, and it stretches or extends to allow the growth of baby throughout the pregnancy months. A woman normally has two types of tubes and two types of ovaries, from which one is on each side of the uterus.
Every month one from these two ovaries in sequence releases an ovum or egg, which slowly passes with the tube in direction to the womb cavity. If within 12 hours of this egg releases, it is not fertilized with the sperm of man or so of being released, it eventually dies; it cannot grow further. But if the woman does the sexual intercourse during her monthly cycle days immediately at or before the time when an egg of a woman has been come out from the ovary, then number of sperm cells discharged by man or her partner may move to the Fallopian tube of woman and in this way one sperm cell may fertilize the woman egg. When the fertilization process has been done and the sperm and nucleus of egg have combined the existence of a new being taken place, which is further capable of the development and called the zygote. As the man and woman are human and belonging to the Homo sapiens species, then as a result the new being is also called human. Fertilization is believed as the starting point of the human lifespan.
The zygote consists on the 46 chromosomes that are considered the inherited blueprint for the development of an individual. It takes approximately nine moths (or 266 days) for the zygote to turn into a fetus of hundred thousand of cells, which is ready to be born. This prenatal development is, in fact, consisted on three periods or stages, i.e., the period of germinal, the period of embryo and the fetal period.
The germinal period remains approximately for fifteen days of two weeks. In the first week or two, the zygote splits a number of times through mitosis creating the blastocyst which is a like a hollow ball which consist approximately 150 cells that in size like a head of a pin. When the blastocyst moves to the uterus approximately on day 6, it implants or inserts tendrils into the blood veins of the uterine wall from its external layer. This is fairly an achievement; merely, around fifty percent of all fertilized ova are implanted successfully in the uterus.
The embryonic period starts from the third week and ends in the eighth week after fertilization or conception. In this short period, all major organs get the shape, in a primitive shape at least, in a process, which is known as organogenesis. Throughout the embryonic period, the cell rate differentiation strengthen, the cells support system form, and organ eventually appears. In three week three, an embryo, the human-to-be is just of 2mm or 1/10 of an inch long. It has stretched out, and as a result three layers develop – the mesoderm, ectoderm, and endoderm.
In the week four, the embryo curved to the extent, which shows that as two ends touch almost. The external layer called an ectoderm crease in the neural tube. From the stage of mesoderm, a little heart develops and starts to beat. The endoderm distinguishes into a gastrointestinal lung and tract. Between 21 days and 28 days, eyes emerge. In the next week, mouth, ears, and throat shapes take place. Buds of arms and legs appear. The important stage of sexual isolation starts in this period. During the last week of this period, the majority of organs and structures are present.
The fetal period starts from the 9th week of pregnancy and remains until the birth takes place. Neuron’s proliferation persists at a stunning rate throughout this period; by one estimation, the figure of neurons intensifies by 250, 000 in every minute all through the period of pregnancy, with an intense proliferation period taking place between ten and twenty weeks after the fertilization. Because of this quick proliferation, the little infant has approximately 100 billion neurons. The system of organs that appeared in the embryonic period persists to develop and start to function. Destructive agents will no longer become the reason of major abnormality since the organs have formed already, but they can exploit the development of the fetus and impede with the wiring of its quickly growing nervous system.
During the third month of getting pregnant, apparent sex organs emerge externally; the muscles and bones develop, and the fetus starts playing. In the end of third month, fetus moves its legs, arms, makes fists, and even revolves around somersaults. Yes, the woman possibly does not feel all these activities since the fetus is approximately three inches long. However, this little being can take food, digest it and urinate. All these activities contribute to the exact and normal development of digestive system, nervous system, and other body systems.
During the fourth, fifth, and sixth month’s period, which is also called second trimester, more developed activities emerge, for example, thumb sucking, and at the end of second trimester the sensory organs start working. Early infants as little as 25 weeks replied to bright lights and loud noise. At around 24 to 25 weeks after fertilization, in the middle of the fifth month, the baby reaches the viability age, when survival external to the uterus is probable if the respiratory and brain systems are sufficiently developed.
During the seventh, eighth and ninth months, which is also called third trimester, the baby starts gains weight rapidly. This time is also critical in the development of the brain, as is the complete prenatal period. In the start of the pregnancy, the primitive structure of the nervous system is developed. And in the second half of pregnancy, the neurons not merely increase at a surprising proliferation rate, but their size also increases and an insulating cover developed that enhance their power to convey signals quickly. Most significantly, directed by both early sensory experiences and a genetic blueprint, the neurons link with each other and arrange into functioning groups that control memory, vision, motor behavior, and some other functions.
Parents, for the good reasons, must think about harm to the growing human in the first three months of pregnancy, which is also called trimester, which is the time of brain and other organs formation. Nonetheless, they must not ignore the importance of the second and third trimesters, which are also significant to normal brain working and thus to normal growth of the infant. As the brain grows, the fetus behavior turns out more like the adaptive and organized behavior that can be seen in the new-born baby. Only at thirty six weeks of development performed heart rate activity and movement turns into more arranged into consistent patterns of sleeping and waking called infant states. They were less irritable, more alert, capable to maintain their concentration, and more obviously to retain the control even in the stressful components of the postnatal analysis.
In the research, it has been found that, with the progress in age; fetal rates of heart turn out more receptive to such a type of stimuli as a vibrator has been placed on the abdomen of mother. On average fetuses moved approximately once in a minute and remain active 25% to 30% of the time. On reaching at 20-week periods, babies spent about 17% of their time only in one or another arranged state of infant, for instance, active sleep, quiet sleep, or active waking. At the end period which is called the prenatal period, they are in one different situation or another at least 80% of the total time.
The babies spent most of the time in snoozing, particularly in active sleep. While in the 20th week of having pregnancy babies are almost never awake and active, by the end of 21st weeks they spend 10% to 16% of their time in a waking, active state. The positions identified in this and other researches recommend that significant changes in the nervous system take place in 28 to 32 weeks after the fertilization, when premature babies are usually well prepared to live. As the nervous system turns our more arranged, so does perform some activities.
In the end of ninth month, the infant is so big that its most relaxed position in the womb heads downward with limbs curled in. The uterus of mother contracts at improper gaps in the last month of pregnancy. When such contractions are frequent, strong, and regular, the woman is in the first phase of labor and in this way the prenatal period comes to an end. In normal situations, birth usually occurs within hours of this phase.
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