Specifics of the twins-Part Four

The most important thing to remember parents of twins, you and all the other children to respect them as individuals, to love each of them, noticing personal successes, avoid extremes and time to respond to children's problems. Having twins is hard happiness, but happiness!
Gemini has since man existed, only that they are born rarely. As is known, there are identical twins (EYAB) - a unique case of equal inheritance and genetic identity and fraternal twins (DYAB) that genetically resemble as much as all the other brothers and sisters.

Identical or fraternal

When we meet twins almost automatically ask ourselves: identical or fraternal?
Most often the answer is obtained at a glance
If twins are heterosexual, the conclusion can generally only be '' fraternal ''. If they have sex, they do not look alike, usually find them also '' fraternal ''. But here already assessment can sometimes be wrong and, because identical twins can have different appearance, driven by severe disturbances during pregnancy, disease, eating disorders or accidents of birth. For anyone interested in a much more complex, but also more attractive task would be to determine what sex twins with great similarity between them. Here the probability of error in the conclusion reached by seemingly too large. Eventually a proper assessment can be reached only after careful comparisons and certain medical anthropological analysis. Today there are many twins or parents of twins who do not know whether, respectively. their children are identical or fraternal.
From a biological point of view and EYAB DYAB differ fundamentally. While EYAB genetic counterparts and have the same hereditary potential DYAB differ genetically as much as all brothers and sisters.
How can you explain this? What biological mechanisms underlying these differences? How to create and EYAB DYAB?
The answer to these questions forces us to make a short and understandable for all introduction to embryology. We need to stop the process of fertilization and the first days after it in order to clarify basically creating the twins. Because whether you conceive twins and what type is decided by fertilization or (at EYAB) in the first two weeks of fetal life.
When people are generally born one child. During each menstrual cycle is usually prepared, and one oocyte is discharged from the ovary with ovulation. It retains its ability to fertilize only from 4 to 20 hours, and passed for 4 to 6 days in the fallopian tube into the uterus. Hence fertilization occurs in the first day following ovulation in the upper part of the fallopian tube. A male reproductive cell penetrates the egg. At the time of penetrating the egg shrinks rapidly and thus be retained by the other germ cells. At this point, new life is emerging genetic combination takes place in the egg. The act of fertilization is determined family, racial and numerous physical signs, construction and function of organs. Here, of course, exclude any pathological processes. Without exaggeration, we can say that this is the most important moment of a person's life, there is no rich in consequences. Shortly after fertilization in the zygote (fertilized egg) occurs division. This process takes place even during transport in the fallopian tube. For about 6 days after ovulation zygote is poselva in the lining of the uterus.