Virgin mothers



Most of the world's multicellular animals reproduce through sexual reproduction, that is, males and females have sexual intercourse, which fertilizes the ovaries of the females with the sperm of the males and produces the next generation. This is because of the diversity of species that leads to evolution - the higher the genetic diversity in any species, the more likely it is that despite the sudden change in the environment. Some people will adapt to the new environment and continue to breed - on the contrary, if the next generation is born asexually, the next generation will inevitably have more or less the same genes as the current generation. This species will lack genetic diversity and will be more likely to become extinct if the environment suddenly changes for some reason.

But there are also some species of multicellular animals in which the female can produce offspring or fertilize eggs without sexual intercourse. I have seen - in wild animals it is practically impossible to see whether an animal is giving birth as a result of sexual intercourse - but in zoos the animals are monitored all the time and the behavior of the animals is observed in every possible way. Is done-

In 2016, male and female sharks laid eggs in separate tanks at an Australian aquarium, but a female shark laid eggs, three of which were hatched. These babies were clones of the female shark, meaning their genes. One hundred percent of these females resembled sharks. Similarly, in a zoo in the United States, a female dragon laid six eggs and all the eggs gave birth to offspring. The female had never seen a male dragon in her life and there was no possibility of that. There was no evidence that the female had sex with a male dragon without being seen by zoo staff - a Komodo dragon in a zoo in England also gave birth to a male without a male.

Let's see how this asexual reproduction is possible - to understand asexual reproduction we must first understand how sexual reproduction takes place.

Sexual reproduction:

Ovaries are formed in the ovaries of females and in the testicles of sperm males - the knowledge of the formation of sex cells is called meiosis - if we take the example of humans, raw cells (including 23 pairs of chromosomes) are involved in this process of meiosis. That is, there are 46 chromosomes (dividing into sex cells), each of which contains 23 chromosomes (half the chromosomes of normal cells).

Each of our cells has 23 pairs of chromosomes, making a total of 46 chromosomes - 23 of which are matched by the mother and 23 by the father - the genes that are found in the normal cells and the genes that are found in the father. They are found in separate strands, ie they do not mix with each other - the process of forming sperms takes place in the testicles where a raw cell divides to form the first two cells in which the genes found in the mother and father mix with each other. (Just like the red and black leaves of a card are separated and when they are spun, the red and black leaves are mixed together) - After this process, each cell has 46 chromosomes, but now the mother and father. The chromosomes of K are not separated but have been mixed together - then each of these two cells divides into two more cells and 23 chromosomes remain in each cell - thus now a total of four cells have been formed. Each of these has 23 chromosomes - each of which will become sperm

In ovaries, the process of cell division takes place in the same way, and from one raw cell, four cells are formed, each containing 23 chromosomes - but the difference is that only one of these four cells forms an ovum and the other three Cells are called polar bodies. Polar bodies do not have organelles like other cells and these cells are not used for reproduction but are lost.

The process of sexual reproduction begins with the union of the ovum and the sperm of the male - when the sperm and the ovum meet, the ovum is fertilized, and the genetic material of the sperm and ovum combines to complete the complete genetic material of the baby. The first cell of the next generation is formed.

This is how reproduction is determined in most multicellular animals in the world - however, some animals do not require sperm for ovulation.

Asexual reproduction:

All unicellular animals reproduce their next generation by asexual reproduction, that is, one cell divides into two cells and copies its genetic material in this process - although in most single-celled animals, most animals reproduce through reproductive reproduction. But there are also some species whose females are capable of reproducing their next offspring from asexual reproduction when needed (ie, if no males are available in the vicinity) - two different processes of asexual reproduction in multicellular animals. Are

We mentioned about sexual reproduction that during the division of cells in the ovaries of a female, where one ovum is formed, three polar bodies are also formed which are not normally useful in reproduction. These polar bodies are similar to the ovaries. This is because they also have half the number of chromosomes as normal cells - but they do not have the rest of the organelles of the cells - sometimes a polar body merges into the ovum instead of being lost and thus the chromosomes in the ovum are completed.

These eggs are also fertile and can give birth to offspring. The offspring of these eggs are always female, but because their genetic material undergoes meiosis, some genes are involved. Mother's genes may be different وہ they always come from one gene in the mother's DNA, from one grandma and from another grandma but in polar bodies and eggs since grandma and grandma's genes have been shuffled Therefore, it is quite possible that in the fertilization of the polar body and the egg, both copies of some genes are from the grandmother and both copies of some genes are from the grandmother - so such children are not clones of the mother. Rather, it may be different from the mother

The second process of asexual reproduction is cloning. In this process, the raw cells do not undergo the process of meiosis, ie they do not divide into cells that have half the number of chromosomes as compared to the rest of the cells, but instead form ovaries directly. The number of chromosomes is complete, that is, each chromosome has two copies, one from the grandparent and one from the grandma. The eggs that are born from such eggs not only have sex, but also sleep. Percentage is their mother's copy

What types of virgin mothers can become:

Asexual reproduction is more common in relatively small invertebrates because it can be difficult for such animals to be close to males for fertilization - insects that live in social environments such as ants, bees, and wasps. I also see asexual reproduction - in addition to vertebrate animals that live either in the desert or on the islands - in both cases there is a possibility. There are no males around the female - these include snakes and many kinds of lizards.

In some animals, despite sexual intercourse with the male, the ovum does not contain the male's genetic material, and the ovum contains only the mother's genetic material - but with the presence of sperm (although this does not include the genetic material of the sperm). As soon as the egg undergoes chemical changes, the egg begins to divide like a fertilized egg - such asexual growth has been observed in salamanders, flatworms, and some other insects.

Even in animals that have asexual reproduction,asexual reproduction occurs only if males are not available - if males are available in the vicinity, females prefer to reproduce by mating with males - however, lizards There are also species in which males have become extinct and only females reproduce through asexual reproduction.

Mammals do not have asexual reproduction.

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