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WHAT YOU NEED TO KNOW ABOUT CHILDBIRTH

                                 The nine-month wait is finally over, and the baby so longed for is about to be born. The expectant mother’s cervix has remained firmly shut, keeping the fetus safely in the womb. But now her cervix thins, softens, and relaxes. The miracle of birth begins.     What is behind the marvelous process of childbirth? Of the several factors involved, two are especially amazing. First, OXYTOCIN , a hormone produced in the brain, is released. Both men and women produce this substance, but a great quantity of it is released in the pregnant mother when labor begins, causing the cervix to dilate and the uterus to contract.        Just how the pituitary gland of the expectant mother knows when to begin releasing this hormones is a mystery. The book incredible Voyage- Exploring the Human Body states: somehow her brain senses that gestation is complete and that it is time for the powerful uterine muscles … to take on their brief but heroic job.  

MYSTERIES SURROUNDING CLONING

                                    In the hands of a trained craftsman, a lump of soft clay can be formed into practical any shape. Embryonic stem cells are the living equivalent of that piece of moist clay; they have the prospective to give rise to virtually all of the over 200 cell types making up the human body. How do they do this? Consider what happens to a newly fertilized egg cell.           Soon after fertilization an egg cell begins to divide. In humans about five days of cell division results in a minute ball of cells called a BLASTOCYST . It is essentially a hollow sphere that is composed of a shell-like outer cell layer and a small cluster of about 30 cells called the inner cell mass, which is attached to the inside wall of the sphere. The outer cell layer becomes the PLACENTA ; the inner cell mass, the human embryo.          At the blastocyst stage, though, the cells of the inner cell mass have not yet begun to specialize into specific cell types, such as nerve

THE MYSTERIOUS PROCESS OF CHILDBIRTH

     The nine-month wait is finally over, and the baby so longed for is about to be born. The expectant mother’s cervix has remained firmly shut, keeping the fetus safely in the womb. But now her cervix thins, softens, and relaxes. The miracle of birth begins.     What is behind the marvelous process of childbirth? Of the several factors involved, two are especially amazing. First, OXYTOCIN , a hormone produced in the brain, is released. Both men and women produce this substance, but a great quantity of it is released in the pregnant mother when labor begins, causing the cervix to dilate and the uterus to contract.        Just how the pituitary gland of the expectant mother knows when to begin releasing this hormones is a mystery. The book incredible Voyage- Exploring the Human Body states: somehow her brain senses that gestation is complete and that it is time for the powerful uterine muscles … to take on their brief but heroic job.        A second factor involved in this