From parent to child : From parent to child

All animals except the simplest, produce special cells, which under favorable circumstances, have the means to evolve into new individuals. These cells are produced by female animals, known as the egg. Egg is often called the Latin word ovum, which means “egg”. Hen’s egg – the egg, with which we are all familiar. In this example, you immediately can see how much egg is different from other cells. Look at the egg and remember that this is just only individual cells. And now compare it with the cells, which are so small that they can only be seen under a microscope. In fact, the living is only a microscopic speck on the surface of the egg yolk. All the rest – just supply food. Chicken will take three weeks to grow out of this microscopic speck in the little creature, filling the shell. The egg must contain all the calories, vitamins and minerals, in which the chicken will need during these three weeks.
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From parent to child : Man and woman

The first question asked of any of the newborn child: “A boy or a girl?” You may ask, when it is determined by the child’s sex. The answer to this may surprise you. Sex of the child is determined at the time when the sperm cell fertilizes the egg.

Let’s see why this is so. As we have said, all human cells (except the egg and sperm cells) contain 24 chromosomes Nara. In fact, it is not entirely correct. The cells of women actually contain 24 committed couples. The cells of males, however, are 23 committed couples, plus 24-th pair, which is a little unusual. 24-th pair of men consists of one chromosome and one perfect little sickly partner. Full-fledged chromosome called the X-chromosome. Chakhlov partner called the Y-chromosome. In other words, the 24-th pair of men do not have an adequate “spare parts”. Continue reading “From parent to child : Man and woman”

From parent to child : Variations among the genes

As we have said, the genes control the development of enzymes and thus control the nature of physical characteristics. Unfortunately, our knowledge of the chemistry of cells is very limited. We can hardly ever know exactly what kind of enzyme or enzymes in the usual physical characteristics. In fact, we know that the enzyme tyrosinase is required for the formation of melanin, and it determines the color of skin, hair and eyes. We believe, however, that this process also requires other enzymes.

For this reason, you can skip the details of the enzyme, and only connect with the physical characteristics of the gene. For example, we could talk about baldness gene, the gene of the five fingers or eye color gene. Sometimes we would feel comfortable talking about the different genes that affect the same physical characteristics, but in different ways. Eye color – a good example. We could talk about the gene for brown eyes and blue eye gene.
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