Scientific Data Surah 86 · Ayah 2
Bootstrap Example
Data Mining and Research:
1. Scientific Data:
Historical background
Since Aristotle had summed up the prevailing theories in his age relating to the creation of the embryo,controversy continued among the supporters of the theory of the full dwarf embryo existing in man’s sperm and those of the theory of the full dwarf embryo created out of the woman’s menstrual blood coagulation (thickening). Most of them believed that man was reduced into that sperm drop, and they drew a figure in which they imagined the embryo as a full creature in the sperm drop, which then grew up in the womb as a small tree.
The dwarf embryo as imagined by Leonardo da Vinci from the 15th century (on the left) and the sperm as miniature human being by Hartsoeker from the 17th century (on the right)
None of both groups could realize that man’s sperm and woman’s ovum participate in the creation of the embryo, as supported by the Italian Scientist “Spallanzani” in the year of 1775. In 1783, Van Beneden was able to confirm this statement, and thus the idea of the dwarf embryo had been discarded. During the years 1888 and 1909 Boveri proved that chromosomes when divided carry the different genetic characteristics. Morgan, in 1912, was able to determine the role of genes, existing in certain parts of chromosomes, in hereditary.
Therefore, it is clear that mankind did not realize that the embryo is created of a man’s sperm mingled with a woman’s ovum except in the 18th century, and only to be confirmed at the beginning of the 20th century.
On the other hand, the Holy Quran and the Prophetic speeches have confirmed in a very accurate scientific manner the creation of man from a mingled fluid-drop (nutfa amshaj), as coined by the Quran, which says ;
( إِنَّا خَلَقْنَا الإِنسَانَ مِنْ نُطْفَةٍ أَمْشَاجٍ نَبْتَلِيهِ فَجَعَلْنَاهُ سَمِيعًا بَصِيرًا) (الإنسان:2)
“Verily We created man from a drop of a mingled fluid-drop (nutfa amshaj), in order to try him: so We gave him (the gifts), of hearing and sight.” (76:2).
It has been agreed upon by commentators of the Holy Quran that “amshaj” means mingling, as man’s water mingles with that of the woman, and this is also what the Prophet (peace be upon him) confirmed in one of his speeches. Imam Ahmed indicated in his book “Al Musnad” that a Jew passed by the Prophet Mohammed (PBUH) while he was addressing his companions. Some people from Quarish said; “O Jew! This man proclaims that he is a prophet.” The Jew said: “I will ask him of something no one knows except a prophet.” He asked the prophet (PBUH); “O Mohammed! What is man created from? The Prophet (PBUH) said; “O Jew! Man is created from both: man’s fluid (nutfa) and woman’s fluid.” The Jew said; “This is said by those prophets before you.”
In the next few pages, the embryological developments as indicated in the Quranic verses will be discussed, while shedding light on the fixed scientific facts in each stage of development.
The Sperm
Scientific facts:
The sperms are formed in the testicles, which in turn are created, as proved by embryology, from cells underneath the kidneys at the back and then go down to the lower abdomen at the last weeks of pregnancy. Man’s fluid mainly contains the following components: the sperms which should be gushing, and motile to cause fertilization and Prostaglandin which causes contractions to the uterus, thus helping the transport of sperms into the place of fertilization. The man's fluid (semen) contains also sugar necessary for providing energy for the sperms, different fluids for neutralizing the acids at the entrance of the uterus and creating a slippery environment for the easy movement of the sperms.
While hundred millions of these sperms (500 m.- 600 m.) enter through the vagina to the uterine cervix, only one sperm is able to fertilize the ovum (Fig. 2); crossing through a long distance to reach the place of fertilization in the Fallopian Uterine Tube which connects the ovary with the uterus. The distance is full of obstacles that can be compared with the distance man takes to reach the moon! After direct fertilization, a quick change occurs to the membrane of the ovum preventing the entrance of the rest of the sperms.
The sperm contains 23 chromosomes, of which one chromosome determines the sex of the embryo. The chromosome in the sperm is either (Y) or (X), while the chromosome in the ovum is always (X). When a sperm of the chromosome type (Y) mingles with an ovum of the chromosome (X), the formed zygote will be male (XY), whereas the embryo will be female (XX) if the sperm (X) mingles with an (X) ovum. So, the sex of the embryo is determined by the sperm (the male), rather than the ovum (the female).
After 5 hours of forming the zygote, which is the primary human cell containing 46 chromosomes, the dominant and recessive genetic characteristics can appear in the parent's sons or grandsons (the stage of genetic programming). The zygote is then divided quickly (Fig. 3) without a change in size and move from the Fallopian Tube (connecting the ovary and the uterus) towards the uterus, where it is implanted as seeds are implanted in the soil.
hundreds of sperms, only one can fertilize the ovum.
The zygote divides within hours of the process of fertilization.
(A picture taken by the Microscope)
The Uterus is the place where the embryo grows and develops before emerging as a fully created and well formed child. The uterus is distinguished as a safe place to perform this function for the following reasons:
1- The location of the uterus in the woman’s pelvis, where it is protected with ligaments and fascia that hold the uterus from the sides and allow its mobility and growth to hundred times its size at full term pregnancy.
2- Muscles of pelvis and perineum fix the uterus in-situ.
3- The secretion of Progesterone (pregnancy hormone) helps stabilize the uterus and slows down the uterine contractions.
4- The embryo in uterus is surrounded with different membranes that produce amniotic fluid which the embryo swims in to protect the embryo from the effect of external traumas .
The process of fertilization and the travel of the zygote to the uterus continue for about 6 days, and the zygote keeps implanting ( known as blastocyst) and growing in the uterus wall for 15 days, when the Alaqa (thick clotted blood) stage begins.
Reflections and comments on related Quranic verses:
“Nutfa” in Arabic means “very little water” or “a drop of water”. This coincides with man’s water which contains sperms as part of its components. The sperm or (spermatozoon) is reproduced from the despised lowly water (nutfa) and looks like a long-tailed fish (this is one of the meanings of Sulalah). Allah the Almighty says;
( الَّذِي أَحْسَنَ كُلَّ شَيْءٍ خَلَقَهُ وَبَدَأَ خَلْقَ الْإِنسَانِ مِن طِينٍ . ثُمَّ جَعَلَ نَسْلَهُ مِن سُلَالَةٍ مِّن مَّاء مَّهِينٍ ) (السجدة :7-8)
“He It is Who created all things in the best way and began the creation of man from clay, and made his progeny from an extract of despised fluid (Sulalah)” (32: 7-8)
The other meaning of Sulalah is "extract", means the essential or best part of something . By either implication, it means "part of a whole" indicating that the origin of creation is from only part of man's fluid and not all of it (which contains many components as shown above) .
Clarifying the role of the nutfa in creation
He the Almighty says;
( فَلْيَنظُرِ الْإِنسَانُ مِمَ خُلِقَ. خُلِقَ مِن مَّاء دَافِقٍ) (الطارق 5-6)
“So, let man consider of what he was created. He was created of gushing water” (86: 5-6)
and also says;
( خَلَقَ الإِنسَانَ مِن نُّطْفَةٍ فَإِذَا هُوَ خَصِيمٌ مُّبِينٌ ) (النحل : 4)
“He has created man from a sperm (fluid-drop) and behold this same (man) becomes an open disputer.” (16: 4).
The Quran tells us also that the essence of man is not the whole semen, but only a small part of it. this is explained in the Quran :
( أَيَحْسَبُ الْإِنسَانُ أَن يُتْرَكَ سُدًى ، أَلَمْ يَكُ نُطْفَةً مِّن مَّنِيٍّ يُمْنَى ) القيامة 36-37
"Does man think that he will be left uncontrolled (without purpose)? Was he not once a fluid-drop of ejected semen?" (75:36-37)
As we have seen, the Quran informs us that man is made not from the entire semen, but only a small part of it. That the particular emphasis in this statement announces a fact only discovered by modern science is evidence that the statement is divine in origin. The divine statement also reiterates that man’s characteristics are determined and decreed in the nutfa stage, as He says
( قُتِلَ الْإِنسَانُ مَا أَكْفَرَهُ . مِنْ أَيِّ شَيْءٍ خَلَقَهُ . مِن نُّطْفَةٍ خَلَقَهُ فَقَدَّرَهُ ) ( عبس17-19)
“Woe to man! What has made him reject (Allah)? From what stuff has He created him? From a nutfa (fluid-drop) He has created him, and then moulds him in due proportions.” (80: 17-19).
And Allah says:
(إِنَّا خَلَقْنَا الإِنسَانَ مِنْ نُطْفَةٍ أَمْشَاجٍ نَبْتَلِيهِ فَجَعَلْنَاهُ سَمِيعًا بَصِيرًا ) (الإنسان:2)
“Verily We created man of a fluid-drop (nutfa), mingling (amshaj), in order to try him: so We gave him (the gifts of) hearing and sight.” (76:2).
The mingled nutfa in this verse reveals the Quran miraculous nature. Nutfa, in Arabic, is a single small drop of water, but it was described here as (amshaj) , which means its structure consists of combined mixtures . This fits with the scientific finding, as the zygote is shaped as a drop, and is simultaneously a mixture of male fluid chromosomes and female ovum chromosomes.
Has anyone ever thought, before the Quran was revealed, that man’s nutfa, when ejected, is responsible for determining if the embryo will be male or female? Has this ever occurred to one’s mind? The Quran says;
( وَأَنَّهُ خَلَقَ الزَّوْجَيْنِ الذَّكَرَ وَالْأُنثَىِ . من نُّطْفَةٍ إِذَا تُمْنَى) ) النجم 45-46 )
“That He created the pairs, male and female, from a fluid-drop sperm as it is emitted.” (53: 45-46), confirming that man’s gender as male or female is determined when the sperm drop is emitted. Who told the Prophet Mohammed that the sperm (nutfa) with one of its types (Y) or (X) is responsible for determining the sex of the embryo? This was not discovered except after the invention of microscopes in the past century, when it was possible then to know that the embryo being a male or female is only determined by the sperm (nutfa), rather than the ovum. In other words, we were in the beginning of the 20th century and the whole of mankind were not aware that the nutfa decrees if the embryo is male or female. While the Quran, which was revealed 14 centuries ago, has stated this fact in a very clear manner.
Here is a remarkable note! We have mentioned earlier that the sperms are formed in the testicles, which in turn are created, as proved by embryology, from cells underneath the kidneys at the back and then go down to the lower abdomen at the last weeks of pregnancy. This is in confirmation of Allah’s saying:
( وإذ أخذ ربك من بني آدم من ظهورهم ذريتهم ) (الأعراف 172)
“And remember when your Lord brought forth from the children of Adam, from their loins, their seeds…” (7: 172).
This is a clear indication that the origin of progeny is at the region of the back where the embryonic testicles are formed. So, praise be to Allah the Omniscient.
The uterus, as mentioned before, is considered as a place settled (Makeen) and safe for the growth and protection of the embryo, according to reasons mentioned earlier. We find that Quran mentions and affirms this fact 14 centuries ago, as He Almighty says:
( فَجَعَلْنَاهُ فِي قَرَارٍ مَّكِينٍ . إِلَى قَدَرٍ مَّعْلُومٍ . فَقَدَرْنَا فَنِعْمَ الْقَادِرُونَ ) ( المرسلات :21-23)
”The which (embryo) We placed in a place of settlement, firmly fixed for a period (of gestation), determined. For We do determine, for We are the best to determine (things). (77: 21-23).
Development of the Male and Female Reproductive Systems
The development of the reproductive systems begins soon after fertilization of the egg, with primordial gonads beginning to develop approximately one month after conception. Reproductive development continues in utero, but there is little change in the reproductive system between infancy and puberty.
Development of the Sexual Organs in the Embryo and Fetus
Females are considered the “fundamental” sex—that is, without much chemical prompting, all fertilized eggs would develop into females. To become a male, an individual must be exposed to the cascade of factors initiated by a single gene on the male Y chromosome. This is called the SRY (Sex-determining Region of the Y chromosome). Because females do not have a Y chromosome, they do not have the SRY gene. Without a functional SRY gene, an individual will be female.
In both male and female embryos, the same group of cells has the potential to develop into either the male or female gonads; this tissue is considered bipotential. The SRY gene actively recruits other genes that begin to develop the testes, and suppresses genes that are important in female development. As part of this SRY-prompted cascade, germ cells in the bipotential gonads differentiate into spermatogonia. Without SRY, different genes are expressed, oogonia form, and primordial follicles develop in the primitive ovary.
Soon after the formation of the testis, the Leydig cells begin to secrete testosterone. Testosterone can influence tissues that are bipotential to become male reproductive structures. For example, with exposure to testosterone, cells that could become either the glans penis or the glans clitoris form the glans penis. Without testosterone, these same cells differentiate into the clitoris.
Not all tissues in the reproductive tract are bipotential. The internal reproductive structures (for example the uterus, uterine tubes, and part of the vagina in females; and the epididymis, ductus deferens, and seminal vesicles in males) form from one of two rudimentary duct systems in the embryo. For proper reproductive function in the adult, one set of these ducts must develop properly, and the other must degrade. In males, secretions from sustentacular cells trigger a degradation of the female duct, called the Müllerian duct. At the same time, testosterone secretion stimulates growth of the male tract, the Wolffian duct. Without such sustentacular cell secretion, the Müllerian duct will develop; without testosterone, the Wolffian duct will degrade. Thus, the developing offspring will be female. For more information and a figure of differentiation of the gonads, seek additional content on fetal development.
During puberty, the release of LH and FSH from the anterior pituitary stimulates the gonads to produce sex hormones in both male and female adolescents.
https://teachmeanatomy.info/the-basics/embryology/reproductive-system/
This article will describe the origins of both male and female sex organs; including the gonads, internal genitalia, and external genitalia.
The reproductive system is a collection of internal and external sex organs which work together for the purpose of sexual reproduction.The development of these reproductive organs begins at an early stage in the embryo.
The Gonads
Indifferent Stage
In the first stage of gonadal development, it is impossible to distinguish between the male and female gonad. Thus, it is known as the indifferent stage.
The gonads begin as genital ridges – a pair of longitudinal ridges derived from intermediate mesoderm and overlying epithelium. They initially do not contain any germ cells.
In the fourth week, germ cells begin to migrate from the endoderm lining of the yolk sac to the genital ridges, via the dorsal mesentery of the hindgut. They reach the genital ridges in the sixth week.
Simultaneously, the epithelium of the genital ridges proliferates and penetrates the intermediate mesoderm to form the primitive sex cords. The combination of germ cells and primitive sex cords forms the indifferent gonad – from which development into the testes or ovaries can occur.
Testes
In a male embryo, the XY sex chromosomes are present. The Y chromosome contains the SRY gene, which stimulates the development of the primitive sex cords to form testis (medullary) cords. The tunica albuginea, a fibrous connective tissue layer, forms around the cords.
A portion of the testis cords breaks off to form the future rete testis. The remaining cords contain two types of cells:
• Germ cells
• Sertoli cells (derived from the surface epithelium of the gland).
In puberty, these cords acquire a lumen and become the seminiferous tubules – the site within which sperm will be formed.
Located between the testis cords are the Leydig cells (derived from the intermediate mesoderm).In the eighth week, they begin production of testosterone – which drives differentiation of the internal and external genitalia.
Ovaries
In a female embryo, the XX sex chromosomes are present. As there is no Y chromosome, there is no SRY gene to influence development. Without it, the primitive sex cords degenerate and do not form the testis cords.
Instead, the epithelium of the gonad continues to proliferate, producing cortical cords. In the third month, these cords break up into clusters, surrounding each oogonium (germ cell) with a layer of epithelial follicular cells, forming a primordial follicle.
The Internal Genitalia
Indifferent Stage
In the first weeks of urogenital development, all embryos have two pairs of ducts, both ending at the cloaca. These are the:
• Mesonephric (Wolffian) ducts
• Paramesonephric (Mullerian) ducts
Male
In the presence of testosterone (produced by the Leydig cells), the mesonephric ducts develop to form the primary male genital ducts. They give rise to the efferent ductules, epididymis, vas deferens and seminal vesicles.
Meanwhile, the paramesonephric ducts degenerate in the presence of anti-Mullerian Hormone produced by sertoli cells in the testes. Its developmental remnant is the appendix testis; a small portion of tissue located on the upper pole of each testicle, which has no physiological function.
Female
In the female, there are no Leydig cells to produce testosterone. In the absence of this hormone, the mesonephric ducts degenerate, leaving behind only a vestigial remnant – Gartner’s duct.
Equally, the absence of anti-Mullerian hormone also allows for development of the paramesonephric ducts. Initially, these ducts can be described as having three parts:
• Cranial – becomes the Fallopian tubes
• Horizontal – becomes the Fallopian tubes
• Caudal – fuses to form the uterus, cervix and upper 1/3 of the vagina.
The lower 2/3 of the vagina is formed by sinovaginal bulbs (derived from the pelvic art of the urogenital sinus).
External genitalia
Indifferent Stage
The development of the external genitalia begins in the third week. Mesenchymal cells from the primitive streak migrate to the cloacal membrane to form a pair of cloacal folds.
Cranially, these folds fuse to form the genital tubercle. Caudally, they divide into the urethral folds (anterior) and anal folds (posterior).
Genital swellings develop either side of the urethral folds.
Male
The development of the indifferent genitalia into the male genitalia is driven by the presence of androgens from the testes, namely dihydrotestosterone (DHT).
There is rapid elongation of the genital tubercle, which becomes the phallus. The urethral folds are pulled to form the urethral groove – this extends along the caudal aspect of the phallus. The folds close over by the 4th month, forming the penile urethra.
The genital swellings become the scrotal swellings, moving caudally to eventually form the scrotum.
Female
Oestrogens in the female embryo are responsible for external genital development. The genital tubercle only elongates slightly to form the clitoris.
The urethral folds and genital swellings do not fuse, but instead form the labia minora and labia majora respectively.
The urogenital groove therefore remains open, forming the vestibule into which the urethra and vagina open.
Decends of gonads
While the gonads arise in the upper lumbar region, they are each tethered to the scrotum or labia by the gubernaculum – a ligamentous structure formed from mesenchyme.
Testes
As the body of the fetus grows, the testes become more caudal. They pass through the inguinal canal around the 28th week, and reach the scrotum by the 33rd week. During their descent, the testes retain their original blood supply, with the testicular arteries branching from the lumbar aorta.
The scrotal ligament is the adult remnant of the gubernaculum.
Ovaries
The ovaries initially migrate caudally in a similar fashion to the testes from their origin on the posterior abdominal wall. However they do not travel as far, reaching their final position just within the true pelvis.
The gubernaculum becomes the ovarian ligament and round ligament of the uterus.
Female reproductive system
https://en.wikipedia.org/wiki/Female_reproductive_system
The female reproductive system is made up of the internal and external sex organs that function in reproduction of new offspring. In the human the female reproductive system is immature at birth and develops to maturity at puberty to be able to produce gametes, and to carry a foetus to full term. The internal sex organs are the uterus, Fallopian tubes, and ovaries. The uterus or womb accommodates the embryo which develops into the foetus. The uterus also produces vaginal and uterine secretions which help the transit of sperm to the Fallopian tubes. The ovaries produce the ova (egg cells). The external sex organs are also known as the genitals and these are the organs of the vulva including the labia, clitoris, and vaginal opening. The vagina is connected to the uterus at the cervix.
At certain intervals, the ovaries release an ovum, which passes through the Fallopian tube into the uterus. If, in this transit, it meets with sperm, a single sperm can enter and merge with the egg, fertilizing it.
Fertilization usually occurs in the Fallopian tubes and marks the beginning of embryogenesis. The zygote will then divide over enough generations of cells to form a blastocyst, which implants itself in the wall of the uterus. This begins the period of gestation and the embryo will continue to develop until full-term.
NEURONAL CONTROL OF EJACULATION
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4896089/
Ejaculation is heavily controlled by the nervous system.
Peripheral Nervous System
Afferents
The main sensory input from the penis comes from the dorsal nerve of the penis, which transmits sensation from the glans, prepuce, and penile shaft. It transmits signals to the upper and lower segments of the sacral spinal cord. The glans contains encapsulated nerve endings, termed Krause-Finger corpuscles, whereas the remaining penile shaft contains free nerve endings. Stimulation of these corpuscles potentiated by stimulation from other genital areas, such the perineum, testes, and penile shaft, play an important role in the ejaculation process. A secondary afferent route is through the hypogastric nerve, which runs through the paravertebral sympathetic chain to enter the spinal cord through the thoracolumbar dorsal roots. The sensory afferents terminate in the medial dorsal horn and the dorsal gray commissure of the spinal cord.
Afferents
The efferent peripheral nervous system constitutes of sympathetic, parasympathetic, and motor nervous components. The soma of the preganglionic sympathetic cell bodies involved in ejaculation are located in the intermediolateral cell column and in the central autonomic region of the thoracolumbar segments (T12-L1).
The preganglionic sympathetic fibers emerge from the ventral roots of the spinal cord and travel through the paravertebral sympathetic chain to relay either directly through the splanchnic nerve, or through relaying first in the celiac superior mesenteric ganglia and then through the intermesenteric nerve, to the inferior mesenteric ganglia. The hypogastric nerve then emanates from the inferior mesenteric ganglia to join the parasympathetic pelvic nerve to form the pelvic plexus, which then sends fibers to the ejaculation structures. The preganglionic parasympathetic cell bodies are located in the sacral parasympathetic nucleus. The sacral parasympathetic nucleus neurons travel then in the pelvic nerve to the post-ganglionic parasympathetic cells located in the pelvic plexus. The motor neurons involved in ejaculation are located in Onuf’s nucleus in the sacral spinal cord, which projects fibers through the motor component of the pudendal nerve to reach the pelvic musculature, including the bulbospongiosus, ischiocavernosus, and external urethral sphincter .
Central Nervous System
Spinal network:The thoracolumbar sympathetic, sacral parasympathetic (mainly sacral parasympathetic nucleus), and somatic sacral Onuf’s nucleus ejaculatory spinal nuclei play an important role in the integration of peripheral and cerebral input and coordinating output to the pelviperineal structures involved in ejaculation (46). An additional spinal center is the SGE located in laminae X and VII of L3-L4 spinal segments ( HYPERLINK "https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4896089/#R51"51). The SGE contains spinal interneurons called lumbar spinothalamic cells, which project fibers to the parvocellular sub parafascicular nucleus of the thalamus in addition to preganglionic sympathetic and parasympathetic neurons innervating the pelvis. The SGE stimulation elicits a complete ejaculatory response resulting in collection of motile spermatozoa in anesthetized rats. Further research on the SGE spinal center is still needed, and it is unclear whether it contains other cells than lumbar spinothalamic cells.
Brain network:Sensory and motor areas in the brain play an important role in the ejaculation, which requires a highly coordinated and integrated central process. The study by Holstege et al. using positron emission tomography showed that certain areas in the brain are activated in the orgasm and ejaculation process. Furthermore, specific areas in the brain have been involved in the ejaculation process, as demonstrated in animal immunohistochemical studies examining Fos protein pattern of expression, and confirmed using a serotonin 1A subtype receptor agonist proejaculatory pharmacologic agent in rats. These are discrete areas within the posteromedial bed nucleus of stria terminalis, the parvicellular part of the subparafascicular thalamus, the posterodorsal preoptic nucleus, and the posterodorsal medial amygdaloid nucleus. There are reciprocal connections that link those areas to the MPOA of the hypothalamus, a brain area with a well-established role in controlling sexual behavior as demonstrated by anatomical and functional studies. Electrical or chemical stimulation of the MPOA elicited ejaculation, whereas an MPOA lesion was shown to abolish both phases of ejaculation. No direct connections of MPOA to the spinal centers for ejaculation were found on neuroanatomical studies; however, there are projections of MPOA to other regions in the brain involved in ejaculation, such as PVN, the periaqueductal gray, and the paragigantocellular nucleus (nPGi).
The PVN projects to pudendal motor neurons located in the L5-L6 spinal segment in addition to autonomic preganglionic neurons in the lumbosacral spinal cord in rats. It also projects to nPGI in the brainstem. Bilateral lesions of the PVN with N-methyl-D-aspartate (NMDA) results in a one-third reduction of the seminal ejaculate material weight. The parvicellular part of the subparafascicular thalamus was found to send projections to bed nucleus of stria terminalis, medial amygdala (MeA), and MPOA and receives input from lumbar spinothalamic cells . The precise role of these regions is still unclear but they are likely involved in relaying genital signals to MPOA. The brainstem regions (nPGI and periaqueductal gray) have recently received increasing attention. The nPGI nucleus likely plays an inhibitory role in ejaculation as evidenced through the urethrogenital reflex experimental model, a rat model for the expulsion phase of ejaculation. Using the same model, the periaqueductal gray was found to be important for the ejaculation process, likely by acting as a relay between MPOA and nPGI. Midbrain structures have a significant role in ejaculation; however, much is still unknown about their exact role and further research is needed.
This figure summarizes the putative brain structures involved in ejaculation.
In conclusion, ejaculation is a complex process involving several anatomical structures and under extensive neurochemical and hormonal regulation.