Chromosomes are present in the nuclei of all cells. Each chromosome contains hereditary instructions - genes.
Deoxyribonucleic acid (DNA) molecules store the information needed to build cellular structures body. DNA molecules are twisted into a spiral and packed into chromosomes. Each DNA molecule forms 1 chromosome. The nuclei of almost all human cells contain 46 chromosomes, and the nuclei of germ cells contain 23 chromosomes. In a DNA molecule, 2 interconnected chains are twisted around one another, forming a double helix. The chains are held together by the nitrogenous bases they contain. There are 4 types of bases, and their exact sequence in the DNA molecule serves as the genetic code that determines the structure and function of cells.
There are about 100,000 genes in the human body. 1 gene is a small section of a DNA molecule. Each gene contains instructions for the synthesis of 1 protein in the cell. Since proteins regulate metabolism, it turns out that genes control everything chemical reactions in the body, determine the structure and functions of our body.
All cells, except sex cells, contain 46 chromosomes, united in 23 pairs. Each pair consists of 1 maternal and 1 paternal chromosome. Paired chromosomes have the same set of genes, presented respectively in 2 variants - maternal and paternal. 2 variants of the same gene responsible for a certain trait form a pair. In a pair of genes, one usually dominates and suppresses the action of the other. For example, if there is a dominant gene on the maternal chromosome brown eyes, and in the father’s, there is a blue gene, the child’s eyes will be brown.
Today scientists are working on the Human Genome Project. They aim to determine the sequence of nitrogenous bases in human DNA, identifying each gene and figuring out what it controls.
Chromosomes
Chromosomes contain thousands of genes. Genes are passed on from parents to offspring. In the ovaries and testes, as a result of a special cell division - meiosis - germ cells (eggs and sperm) are formed with a unique set of genes in which new hereditary properties are encoded. Individual characteristics different people are caused precisely by different combinations of genes. Sex cells contain 23 chromosomes. During fertilization, the sperm fuses with the egg and the full set of 46 chromosomes is restored. 1 pair of chromosomes, namely the sex chromosomes, differs from the other 22 pairs. In males, the longer X chromosome is paired with the shorter Y chromosome. Women have 2 X chromosomes. The presence of XY chromosomes in the embryo means it will be a boy.
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It is quite logical that any couple expecting or planning procreation is interested in what determines the sex of the child. Unfortunately, the issue of a baby’s gender is surrounded by illogical myths that contradict common sense and the laws of biology and physiology.
In our article we will dispel these myths and figure out what the sex of a person’s child depends on, and also consider who exactly it depends on – a man or a woman. We will separately touch upon the question of what determines the sex of a child when conceiving a child, and how this process can be influenced.
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Each human somatic cell contains 23 pairs of chromosomes, which carry genetic information - such a set of chromosomes is called diploid (46 chromosomes). 22 pairs are called autosomes and do not depend on the sex of the person; therefore, they are the same in men and women.
The chromosomes of the 23rd pair are called sex chromosomes, since they determine gender. These chromosomes can differ in shape, and they are usually designated by the letters X or Y. If a person has a combination of X and Y chromosomes in the 23rd pair, this is a male individual; if these are two identical X chromosomes, it is female. Therefore, cells female body have a set of 46XX (46 chromosomes; identical sex X chromosomes), and males have a set of 46XY (46 chromosomes; different sex X and Y chromosomes).
Human sex cells, sperm and eggs, contain 23 chromosomes instead of 46 - this set is called haploid. This set of chromosomes is necessary for the formation of a diploid zygote - a cell formed by the fusion of a sperm and an egg, which is the first stage of embryo development. But still, the gender of the child depends on the man. Why? Let's figure it out now.
Chromosome set of man and woman
On whom does it depend more - on a woman or a man?
Many people still ask the question: “Who determines the gender of a child: a woman or a man?” The answer is obvious if you understand which sex chromosomes the sex cells carry.
An egg always has a sex X chromosome, but a sperm can contain both an X and a Y chromosome. If the egg is fertilized by a sperm with an X chromosome, the sex of the baby will be female (23X+23X=46XX). In the case when a sperm with a Y chromosome fuses with an egg, the sex of the child will be male (23X+23Y=46XY). So who determines the gender of the child?
What gender the child will be depends purely on the sperm that fertilizes the egg. It turns out that the gender of the child depends on the man.
What determines the sex of a child at conception? This is a random process when the probability of fertilizing an egg with one or another sperm is approximately the same. The fact that the baby will be a boy or a girl is a coincidence.
Women with feminist inclinations will either have to accept the fact that the gender of the child depends on the man, or women will try long and tediously to influence themselves by modifying their diet, frequency of sexual intercourse and sleep time, without in any way increasing the likelihood of having a boy or a girl. .
Why exactly does a sperm with a Y chromosome fertilize an egg?
During the ovulatory phase menstrual cycle The egg is released into the fallopian tube. If at this time a woman has sexual contact with a man, the sperm in the semen enter the vagina, the cervical canal, and then into the uterus and fallopian tubes.
On the way to the egg, sperm have many obstacles:
- acidic vaginal environment;
- thick mucus in the cervical canal;
- reverse flow of fluid in the fallopian tubes;
- woman's immune system;
- corona radiata and zona pellucida.
Only one sperm can fertilize an egg, and this sperm can be either a carrier of the X chromosome or the Y chromosome. The position in which sexual intercourse occurs, what diet the man followed, etc. does not affect which sperm will be the “winner”.
There is an opinion that X-sperm are more resistant to the “aggressive” environment in the female genital organs, but at the same time they are slower than Y-sperm, but there is no reliable evidence for this.
Why shouldn’t folk methods and signs be taken seriously?
But because if you turn on logic and common sense, they have no justification. What are these methods?
- Ancient calendar methods, for example:
- Chinese method of sex planning depending on the woman’s age and month of conception;
- Japanese method, where the sex of the baby depends on the month of birth of the mother and father;
- Methods associated with sexual intercourse: abstinence (for the appearance of a girl) and unrestraint (for the appearance of a boy), various positions as a predictor of the male or female gender of the baby;
- Dietary Methods:
- to get a girl child - foods with calcium (eggs, milk, nuts, beets, honey, apples...);
- to get a boy child - foods with potassium (mushrooms, potatoes, oranges, bananas, peas...).
Now let’s put everything into pieces.
Chinese and Japanese methods involve the use of special tables to predict the sex of the baby. Who determines the sex of a child at conception? From the sperm that will fertilize the egg. The Chinese stubbornly believed that the sex of the baby depends on the mother, therefore, this method is already devoid of any logical rationale.
Does the sex of the fetus depend on the woman? In any case, the egg contains only the X chromosome, therefore, it is not responsible for whether a girl or a boy is born.
You can rely on the Japanese method if you firmly believe that the compatibility of couples is determined solely by the horoscope, because the essence of this option for determining gender is the same. Let’s remember what determines the sex of the unborn child at conception by studying this method!
Can the dates of birth of two partners influence the fact that after many years the X- or Y-sperm will be the most agile and powerful from a man’s sperm? Especially considering the randomness of the latter. This also includes all kinds of methods that promise the birth of a child of one gender or another depending on the day of the menstrual cycle.
Another way to determine the sex of the unborn child
The pace of sexual activity, as well as diet, can affect the quality of sperm and the likelihood of fertilization, but not the gender of the potential baby. Modifications of sexual life are not among those factors on which the sex of the unborn child depends, since they cannot speed up movement or increase the endurance of the “same” sperm.
Yes, both X- and Y-spermatozoa differ not in the amount of calcium and potassium, but only in a fragment of a chromosome containing DNA. And there’s no need to talk about a woman’s influence at all - we all remember which parent determines the gender of the child.
Hence, traditional methods planning the sex of a baby are based on myths and ignorance of the peculiarities of the fertilization process, therefore they cannot be taken seriously. But you will find out what methods you can use to determine pregnancy at home.
Does the sex of the fetus affect the occurrence of toxicosis?
What was previously called toxicosis is now called gestosis. Preeclampsia is the result of pathological adaptation of the female body to pregnancy. The causes of gestosis include disruption of hormonal regulation of pregnancy, immunological changes, hereditary predisposition, peculiarities of placenta attachment and many other factors.
Preeclampsia manifests itself in the form of hemodynamic disturbances (for example, an increase in blood pressure), deterioration of the function of the urinary system (nephropathy of pregnancy, manifested in the form of edema, the appearance of protein in the urine, etc.), in severe cases, a pathology of blood clotting is observed.
To the popular question “Does toxicosis depend on the gender of the unborn child?” There is only one answer: definitely not. None of the factors that cause gestosis can be influenced by the gender of the fetus.
All the first signs of pregnancy are described in detail in. A – it is described at what time and with the help of ultrasound you can reliably find out the sex of the unborn child.
Useful video
It is known that the sex of the unborn child is determined at the moment of conception and depends on which sperm fertilizes the egg. Is this connection random, or can it be influenced in some way:
Conclusion
- Sperm are produced by the male gonads, which suggests who determines the sex of the unborn child.
- The fact that an egg can be fertilized by a sperm with both an X and a Y chromosome answers the question why the sex of a child depends on the father and not on the mother.
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