What is the difference between ovogenesis and spermatogenesis?

In this paper, we suggest distinguishing the difference between ovogenesis and spermatogenesis, and talking about these processes themselves. Of course, we will not disregard sex cells, we will also explain their structure and functions in detail.

Reproduction is the main purpose of all living creatures of our planet, it helps to continue the race, that is, our planet will never become empty. On the contrary, now the number of living beings, especially people, grows exponentially. The egg and spermatozoa are the sex cells of women and men, respectively. Our article will be devoted to them. By gametogenesis is understood the process of formation of sex cells. If we are talking about spermatozoa, then it has the name spermatogenesis, if it's about eggs, then oogenesis. All this in more detail you will learn further.

Gametogenesis

Ovogenesis and spermatogenesis, the difference between them is not critical, have many similar features, can be called one common term - "gametogenesis." Now this is a little more detailed.

To begin with, we will analyze the concept itself, we can distinguish two words: "gamete" and "genesis," the latter from the Greek language can be translated so - "origin". That is, literally the term "gametogenesis" means "the origin of gametes." Gametes are germ cells, men have spermatozoa, women have oocytes. The gametogenesis itself can also be divided by sex: gametogenesis, occurring in the body of a man, is called spermatogenesis, and in the body of a woman - oogenesis. But here we come to the first difference of these processes. Ovogenesis begins before the birth of a girl, and spermatogenesis is manifested in boys who reached a certain age, usually 12-13 years.

Sexual maturity of girls

The process of egg formation, that is, oogenesis, occurs still in the womb, while puberty, or rather, its first stage, is about nine years. We suggest a little more to consider the stages of puberty girls:

• 1st stage - increased growth, there are cases when the girl is gaining more than 10 centimeters in height, this is considered the norm. As a rule, now girls outrun boys.
• 2-nd step - a change in secondary sexual characteristics. At about 12 years old, the girl begins to leave the image of an ugly duckling. The breast begins to grow, the waist decreases, the hair grows in the pubic region and in the armpits. Approximately at this stage, conserved egg cells wake up and begin their further development. Soon the girl will find out what the monthly ones are.
• The third stage is the final stage. He has about 18 years. Now the girl is considered fully formed, she can reproduce healthy offspring.

Sexual maturity of the boy

As we mentioned earlier, girls form eggs in the womb, the boys are doing it a little differently. Spermatozoa begin their development only when they reach 12-14 years. Before this stage of puberty there are also changes:

• Increase in penis size;
• Increased scrotum;
• Grow hair on the pubic area, in the armpits, on the legs and face.

At the age of 12-14, a young man can begin to lead a sexual life, but his parents should warn him, because he can already cause unwanted early pregnancy of his companion. Now let's go directly to the male and female sex cells, consider their structure, the stages of formation, similarity and difference.

Egg

Let's start with the female sex cells, the characterization of the oogenesis will be considered a little later. First we suggest to consider the structure and functions of the egg.

The egg is a relatively large and immobile cell, its dimensions reach 170 microns, which is much larger than the male sex cells (up to 70 microns). Each of them contains the necessary nutrients, where we will see:

• Substances necessary for protein biosynthesis;
• Regulatory substances;
• yolk.

Cells can be divided by the amount of yolk:

• On the alecital;
• Polycital;
• Mesocyt;
• Oligolecital.

From a negligible amount to a very large, respectively. If we consider a female egg, then it can be attributed to the alecital and isoletsitalnuyu type. That is, it has little yolk, which can be explained by the fact that the human embryo quickly passes to the hematotrophic type of nutrition. Isoletsitalny type means that the yolk is distributed evenly and the core is in the center.

The egg has the following shells:

• cytoplasm;
• protective shell;
• Radiant crown.

All shells have a protective function, they do not allow to penetrate into the ovum more than one sperm needed for fertilization. All others are blocked.

Now select the functions of the egg:

• Providing the embryo with energy;
• Provision of nutrients at the initial stage of the embryo.

Sperm

Everyone knows that a sperm is a male germ cell, but how is it arranged? We suggest to sort out this question a little. You can see the appearance of gametes in the photo of this section. In its structure, the following parts can be distinguished:

• head;
• neck;
• middle part;
• tail.

The head of the spermatozoon is filled with the nucleus, it is she who carries the hereditary information. During fertilization, the oocyte passes precisely it. The sex of the unborn child depends on the sperm. If he carries the X chromosome, then there will be a girl, if Y, then a boy.

The neck is represented as a small narrowing in front of the middle part of the spermatozoon, it is this part that is responsible for the active movement, otherwise it would be impossible to fertilize.

Next comes the body, which also generates energy for the movement of gametes. The tail is represented by a flagella, which performs a very important task - movement.

Before we look at the peculiarities of spermatogenesis and oogenesis, we propose to highlight the basic function of spermatozoa - this is the communication of the genetic material to the egg.

Ovogenesis

Let's start with the formation of the female sexual cell, select the periods of oogenesis and characterize each of them. So, the phases are:

• Reproduction;
• Growth;
• Maturing.

Now we can already name the first difference in ovogenesis from spermatogenesis: in the first case, the birth of female sex cells (oocytes), and in the second - the male (sperm cells). Let's characterize each stage of oogenesis.

At the stage of reproduction, the original cells (germinal) in the parenchyma are divided by mitosis. Thus, the accumulation of ovonia occurs in the cortical layer of the ovaries. They accumulate:

• Proteins;
• Fats;
• Glucose.

Now they are very different from their predecessors, the resulting ovony is much larger than the rudimentary, but their genetic makeup is identical. It is also important to note that this process takes place before the birth of the girl, that is, in the womb of the mother.

The next stage occurs shortly before the girl's birth. This stage is usually called growth. Now there is a division of mitosis, this is how the oocytes of the first order are formed. In comparison with ovoniyami they become smaller, but then rapidly increase in size. Now the oocytes are waiting for a slight embarrassment, they are trapped in the granulosa and stop at the stage of the primordial follicle. In total there are about two million such cells, but only a few will develop further (approximately 450).

The third stage (maturation) occurs shortly before the appearance of the first monthly girls. One of the fallen asleep follicles wakes up and continues its development, which stopped about 12-13 years ago.

Spermatogenesis

We have already singled out one difference between ovogenesis and spermatogenesis (different sex cells develop), one can also distinguish from the read that the ovogenesis begins before the girl's birth, while the process of spermatogenesis - at the age of 12-14. We have already identified two differences, then we will denote this once again to consolidate knowledge.

Stages of spermatogenesis also differ slightly from the stages of ovogenesis (the presence of another stage). The following stages of spermatogenesis are distinguished:

• Reproduction;
• growth;
• maturation;
• Formation.

Here we see the similarity of these processes, the first three stages are the same, only at the stage of maturation oogenesis ends, and spermatogenesis continues, the stage of formation begins.

Differences

You have almost finished reading this article, try it yourself - name the differences between spermatogenesis and oogenesis. Now check how you did the job.

The first difference between ovogenesis and spermatogenesis is the different start time of the process. In girls, the process of gametogenesis begins during intrauterine development, in boys - at 12-14 years.

The second difference is that in the process of ovogenesis, egg cells develop, and spermatogenesis develops spermatozoa.

The third difference is the life span of germ cells. The sperm live from a hundred to one hundred and ten days (if you take into account the whole process of spermatogenesis, about 74 days), the female reproductive cell is the result of a long wait in the ovary (12 to 40 years).

The fourth difference is the number. For all of life, men come to light many hundreds of billions of spermatozoa, and completely all stages of ovogenesis pass about 450 eggs.

Similarities

During the writing of the article, we distinguished both similarities and differences in spermatogenesis and oogenesis. Now once again we generalize, we will designate in the form of a list of similarities of these processes.

• Three common stages (reproduction, growth, maturation).
• Spermatocytes and oocytes are formed by mitosis.
• The growth stage in both ovogenesis and spermatogenesis is characterized by an increase in gametes.
• The stage of ripening occurs by meiosis.