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Week 4 of Pregnancy
by HFCadmin ·
Week 4. At the end of this week you wonder where zapropastilis monthly, and you begin to suspect they are pregnant. Your child is on the third day after fertilization, began to produce the hormone hcg (human chorionic gonadotropin). During this week your child a zygote becomes an embryo, and so we call it before the 10th week. At the end of the week your baby is the size of 0,4-1 mm – as a grain of sand. Week 5. Notice the amazing (for those who have not yet had children), fatigue, breasts can become super sensitive. Last week the child consisted of two layers, this week added a third.
Ectoderm becomes the skin, hair, nervous system, tooth enamel. Endoderm will develop in the limbs and digestive tract. Mesoderm becomes a skeleton, muscles, excretory, reproductive and circulatory systems. On the back of the embryo is formed a groove, which is folding, will be nervous tube. Neural tube sequence becomes a chord, spinal cord and nervous system. By the end of the week on both sides of the neural tube formed segments – prototypes of the muscles and bones. It starts with the formation of cardio- vascular system. First of all mesodermal cells flasks appear – in a child, in the yolk sac and in a yellow body. In the chest there is a primitive heart – a tube, at the end of the week blood cells come from the shell yolk sac and are sold through a child by contractions of the heart-tube.
Tags: women's health
