Your child's heredity
Your contribution to the genetics of a child is determined at the time of conception. Half of it falls on the ovule, and the other half on the sperm. Therefore, it does not matter to whom the child will look like, and you and your spouse, from the point of view of his heredity, have made an equal contribution.
The process of influencing the parameters of your child is surprisingly complex, but it is very easy to understand the natural rule to which it obeys. To better understand how you and your spouse affect the child's parameters, you should first clarify some of the basic provisions of genetics.
GENES AND CHROMOSOMES
Your body consists of millions of cells, each of which is a copy of the fertilized egg from which you derived, and the nuclei( centers) of these cells contain copies of all your genes. Genes are drawings that are for your body a task to form, when you were an embryo, and determine its functions now. These drawings are encoded in DNA.
This acid affects how your child will look. Eye color and visual acuity, hair structure, nose shape, blood type, physique and many other parameters of the child are determined by its genes, which he inherits from you, and you inherited from your parents. In each of the millions of cells there are approximately 30,000 genes, so it is difficult to imagine how small they are - they can only be seen in a very powerful microscope. The combination of these genes makes each person unique.
Genes do not float freely inside cells, they are systematically packaged into structures called chromosomes. Usually in every cell your child has 46 chromosomes that are linked in pairs. One chromosome from each pair is yours, and the other is your partner. A single chromosome carries thousands of genes and is large enough to be seen in a powerful microscope.
YOUR GENETIC STRUCTURE
Who do you look more like-mother or father? You have one pair of genes for each of the parameters: one gene from the mother and one from the father. For some parameters, both of your parents may have given you the same version of the gene, for others - different. Sometimes one variant of the gene prevails over the other, in other cases both equally affect the result. It is the general effect of the combination of all genes that determines your hereditary structure.
Variety - is the spice of life
Many genes exist in a variety of different shapes, reminiscent of the huge number of recipes for baking a chocolate cake. If it were not, all people would look quite similar, and the world would be a very boring place. Because there are so many genes that you inherit from your
parents, you are a genetically unique creature, unless you have the same twin. Even your brothers and sisters will be genetically different, because their genetic heredity is completely dependent on the unique combination of genes partly derived from the egg and partly from the sperm that will manifest in your child and any other children you later give birth.
Some genes are not formed correctly. If both of the two genes are abnormal, this can lead to problems such as fibrosis-cystic degeneration or sickle cell anemia.
Who will your child look like?
If you and your spouse have completely transferred the entire set of 46 chromosomes to an egg and sperm, then your child will have 92 chromosomes in his cells, and their number will double with each generation. Such a system will not work. Instead, in the formation of eggs and spermatozoa, the cells undergo a special division, in which a certain number of chromosomes is formed inside each, therefore, each ovum and sperm contain only 23 chromosomes. Thus, for any given chromosome, you will give your child either the one that they received from their mother or the one they received from their father;your spouse will do the same.
Your child will receive some chromosomes that you inherited from both parents,
so he can have, for example, the physique and color of your father's hair, but the color of his eyes will be like your mother's. If in the future you plan to increase the family, your next child will inherit a slightly modified combination and become another unique addition to your family.
Non-functioning gene
Your child can inherit genes that you did not even know existed. For example, a child may have red hair, even if neither you nor your spouse have any. This is due to the fact that some genes predominate, and some are suppressed, and in pairs of emerging chromosomes, the predominant genes "overwrite" information recorded on recessive genes. Therefore, both you and your spouse can carry a gene of black hair that predominates, and a gene of red hair that is suppressed. In each of you the gene of black hair dominates. However, if both of you gave your child a gene for red hair, then the prevailing gene will be absent, the and will have red hair.
How chromosomes determine the sex of a child
Like physical parameters, your child's sex is laid at the moment of conception. Of the 23 pairs of chromosomes, only one determines who will turn out - a boy or a girl. This decisive pair is the chromosomes of the sex: X and Y. The girls have two X chromosomes, the boys have one X chromosome and one Y chromosome. Because of the way in which the egg and sperm are generated, all the eggs contain one X chromosome. Half of the spermatozoa contain the X chromosome, the other half the Y chromosome. When fertilization, when the sperm and the egg unite their chromosomes, the girl turns out if the sperm carries the X-chromosome, the and the boy, if it carried the Y-chromosome. Ironically, historically, women have been blamed for not giving birth to boys, although the sex of the child is always determined by the father's sperm that fertilized the egg