Conception To Birth

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Conception to Birth About one month before conception almost all adult produce thousands of sperm each second. The number of chromosomes in each sperm produced is half the normal number 23 instead of 46. They take a month or so to travel from a testicle through a long tube. Each sperm counts human DNA but only one complete a set of chromosomes. One day before conception the woman ovulates and produces one mature ovum. During the conception process one sperm out of millions by the man may penetrate the outside layer of the ovum and fertilize it. The start of pregnancy is about 10 days after conception. 14 days after conception it has now developed into the fetus central nervous system. Its heart begins to beat and at this time the woman might have noticed that her menstrual period is late. During the first month of pregnancy (4weeks) the baby develops into about 1/5 inch long. The structure that will develop into a head is visible which a noticeable tail is. The embryo has structures like gills of a fish in the area that will later develop into a throat. The heart, digestive system, backbone and spinal cord begin to form also the placenta begins to develop. Hands with web between the fingers have formed during the second month of pregnancy (8 weeks). The heart is functioning. Eyes, nose, lips, tongue, ears, and teeth are forming. Baby is moving even though the mother cannot yet feel the movement. The baby will now be 1-1/8 inch long. Nails start to develop and earlobes are formed. Arms, hands, fingers, legs, feet, and toes are fully formed. The eyes are almost fully developed. Also the baby has developed most of he/she organs and tissues, reaching the weight of ½ to an ounce in the third month (12 weeks). When reaching the fourth month (16 weeks) will be very exciting for the parents because the sex is identifiable. The baby is developing reflexes, such as sucking
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