Unit 12 Physiology of the Human Regulation and Reproduction Assignment 4: The Reproductive System
P6. Explain the roles of the sex organs in production of ova and sperm/ P7. Explain how the structure of the reproductive system relates to their functions
Male Reproductive System
The male reproductive system consists of organs; having functions that produces a new individual, to accomplish reproduction. The male reproductive system consist of t a pair of testes, also having a network of excretory ducts (epididymis, ducts deferens vas deferens), and the ejaculatory ducts), prostate, seminal vesicles, the bulbourethral glands and the penis.
Every testis is an oval structure around 5 cm long and 3 cm in diameter. It has a tough, white stringy connective tissue capsule which the tunica albuginea, encompasses every testis and stretches out internally, in order to help keep form septa that partition of the organ into lobules. There are roughly around 250 lobules in each testis. Each lobule contains about 1 to 4 highly coiled seminiferous tubules that focalize to shape a solitary straight tubule, which therefore leads into the rete testis. Short efferent ducts leave the testicles. Interstitial help produces male sex hormones, are situated between the seminiferous tubules inside a lobule.
• Testes –The male gonads, testes or testicles, begin their improvement high in the abdominal cavity, close to the kidneys. In the most recent of two months before birth, or not too long after birth, they begin to descend through the inguinal canal into the scrotum, the pouch that extends below the abdomen, then posterior to the penis. In spite of the fact that this area of the testicles, outside the abdominal cavity, may appear to make them vulnerable to injury, it gives a temperature at around 3° C below the body’s normal temperature. This lower temperature is vital for the production of viable sperm.
• Epididymis –The sperm leaves the testicles through an efferent duct that enters the epididymis. Each of the epididymis is a long tube that is tightly coiled up to frame a comma-shaped organ, which are located superior and posterior margins of the testicles. The process of the maturation is then finished when they later on become fertile, as they travel through the epididymis. The mature sperm will be put away at places in the lower portion, or tail, of the epididymis.
• Scrotum –The scrotum mostly consists of skin and subcutaneous tissue. The vertical septum, or segment, of subcutaneous tissue in the centre partitions it into two sections, as each containing one testis. However, the smooth muscle fibres, in the subcutaneous tissue contracts to give the scrotum its wrinkled appearance. At the point when these fibres are relaxed, the scrotum is smooth. Another muscle, the cremaster muscle, comprises of skeletal muscle fibres and controls the position of the scrotum and testicles. When it is cold or a man is sexually aroused, this muscle contracts to pull the testicles nearer to the body for warmth.
• Vas Deferens – The ductus deferens, also known as vas deferens, is a fibromuscular tube that is persistent with the epididymis. It starts at the bottom (tail) of the epididymis at that point turns sharply upward along the posterior margin of the testicles. The ductus deferens enters the abdominopelvic cavity through the inguinal canal and goes along the lateral pelvic wall. It traverses the ureter and posterior portion of the urinary bladder, and after that descend along the posterior portion of the bladder toward the prostate gland. Just before it achieves the prostate gland, each ductus deferens enlarges to form an ampulla. Sperm are put away in the proximal segment of the ductus deferens, close to the epididymis, and movements propel the sperm through the tube.
The proximal part of the ductus deferens is a segment of the spermatic cord, which contains vascular and neural structures that supply the testicles. The spermatic cord contains the ductus deferens, testicular artery, veins, lymph vessels, testicular nerve and cremaster muscle that raises the testicles for warmth and now and again of sexual stimulation, and a connective tissue covering.
• Penis –The penis, is the male copulatory organ, has a cylindrical and hollow pendant organ found in the anterior to the scrotum and is functioned to transfer the sperm to the vagina. As the penis comprises of three sections of erectile tissue that are enclosed by connective tissue and which is covered with the skin. The two dorsal sections are the corpora cavernosa. The single, midline ventral section encompasses the urethra and is known as the corpus spongiosum. The penis has a root, body (shaft), and glans penis. The foundation or root of the penis appends it to the pubic curve, and the body is the visible to the pendant portion. The corpus spongiosum expands at the distal end to form the glans penis. The urethra, which reaches out all through the length of the corpus spongiosum, opens through the outside urethral orifice at the tip of the glans penis. A loose fold of skin, called the prepuce, or foreskin, covers the glans penis.
• Accessory Glands –The accessory glands of the male reproductive system are the seminal vesicles, prostate gland and the bulbourethral glands. These glands secrete fluids that enter the urethra.
Sperm are created by spermatogenesis inside the seminiferous tubules. A transverse area of a seminiferous tubule demonstrates that it is pressed with cells in different phases of improvement. Packed with these cells, there are expansive cells that reach out from the periphery of the tubule to the lumen. These vast cells are the supporting, or sustentacular cells which bolster and sustain alternate cells.
At the early stage of the embryonic development, the primordial germ cells enter the testicles and differentiate into spermatogonia, as the immature cells that remain dormant until puberty. Spermatogonia are diploid cells, each with 46 chromosomes (23 pairs) situated around the periphery of the seminiferous tubules. As puberty, hormones stimulate these cells to start partitioning (dividing) by mitosis. A few of the female cells in which is produced by mitosis stay at the periphery as spermatogonia. However, the other are pushed toward the lumen, a few changes, and become primary spermatocytes. Since they are created by mitosis, the primary spermatocytes, as spermatogonia, are diploid and have 46 chromosomes.
Each primary spermatocytes goes through the first meiotic division, meiosis I, to produce two secondary spermatocytes, each with 23 chromosomes (haploid). Just prior to this division, the genetic material is replicated so that each chromosome consists of two strands, called chromatids that are joined by a centromere. During meiosis I, one chromosome, consisting of two chromatids, goes to each secondary spermatocytes. In the second meiotic division, meiosis II, each secondary spermatocytes divides to produce two spermatids. There is no replication of genetic material in this division, but the centromere divides so that a single-stranded chromatid goes to each cell. As a result of the two meiotic divisions, each primary spermatocyte produces four spermatids. During spermatogenesis there are two cellular divisions, but only one replication of DNA so that each spermatid has 23 chromosomes (haploid), one from each pair in the original primary spermatocytes. Each successive stage in spermatogenesis is pushed toward the centre of the tubule so that the more immature cells are at the periphery and the more differentiated cells are nearer the centre.
Spermatogenesis (and oogenesis in the female) differs from mitosis because the resulting cells have only half the number of chromosomes as the original cell. When the sperm cell nucleus unites with an egg cell nucleus, the full number of chromosomes is restored. If sperm and egg cells were produced by mitosis, then each successive generation would have twice the number of chromosomes as the preceding one.
The final step in the development of sperm is called spermatogenesis. In this process, the spermatids formed from spermatogenesis become mature spermatozoa, or sperm. The mature sperm cell has a head, midpiece, and tail. The head, also called the nuclear region, contains the 23 chromosomes surrounded by a nuclear membrane. The tip of the head is covered by an acrosome, which contains enzymes that help the sperm penetrate the female gamete. The midpiece, metabolic region contains mitochondria that provide adenosine triphosphate (ATP). The tail or locomotor region uses a typical flagellum for locomotion. The sperm are released into the lumen of the seminiferous tubule and leave the testes. They then enter the epididymis where they undergo their final maturation and become capable of fertilizing a female gamete.
Sperm production begins at puberty and continues throughout the life of a male. The entire process, beginning with a primary spermatocyte, takes about 74 days. After ejaculation, the sperm can live for about 48 hours in the female reproductive tract.
Additionally, in each of the primary spermatocytes goes through a first meiosis division, to create two optional spermatocytes, each with 23 chromosomes (haploid). The genetic material is replicated for each of the chromosomes comprises of two strands, called chromatids that are joined by a centromere. I, one chromosome, comprising of two chromatids, goes to every auxiliary spermatocytes. In the second meiotic division, meiosis II, every optional spermatocytes partitions to create two spermatids. There is no replication of hereditary material in this division, however the centromere isolates with the goal that a solitary stranded chromatid goes to every cell. Because of the two meiotic divisions, every essential spermatocyte produces four spermatids. Amid spermatogenesis there are two cell divisions, yet just a single replication of DNA with the goal that every spermatid has 23 chromosomes (haploid), one from each combine in the first essential spermatocytes. Each progressive stage in spermatogenesis is pushed toward the focal point of the tubule so the more juvenile cells are at the outskirts and the more separated cells are closer the inside.
Spermatogenesis (and oogenesis in the female) contrasts from mitosis on the grounds that the subsequent cells have just a large portion of the quantity of chromosomes as the first cell. At the point when the sperm cell core joins with an egg cell core, the full number of chromosomes is re-established. On the off chance that sperm and egg cells were created by mitosis, at that point each progressive age would have double the quantity of chromosomes as the previous one.
The last advance in the improvement of sperm is called spermatogenesis. In this procedure, the spermatids framed from spermatogenesis end up develop spermatozoa, or sperm. The develop sperm cell has a head, midpiece, and tail. The head, likewise called the atomic locale, contains the 23 chromosomes encompassed by an atomic layer. The tip of the head is secured by an acrosome, which contains catalysts that assistance the sperm infiltrate the female gamete. The midpiece, metabolic district contains mitochondria that give adenosine triphosphate (ATP). The tail or locomotor locale utilizes a commonplace flagellum for velocity. The sperm are discharged into the lumen of the seminiferous tubule and leave the testicles. They at that point enter the epididymis where they experience their last development and end up fit for preparing a female gamete.
Sperm generation starts at pubescence and proceeds for the duration of the life of a male. The whole procedure, starting with an essential spermatocyte, takes around 74 days. After discharge, the sperm can live for around 48 hours in the female regenerative tract.
Female Reproductive System
The organs of the female reproductive system produce and sustain the female sex cells. As these transport these cells to a site where they may be fertilized by sperm, provide a favourable environment for the developing fetus, move the fetus to the outside at the end of the development period, and produce the female sex hormones. The female reproductive system includes the ovaries, Fallopian tubes, uterus, vagina, accessory glands, and external genital organs.
The ovaries are covered on the outside by a layer of simple cuboidal epithelium called germinal (ovarian) epithelium. This is actually the visceral peritoneum that envelops the ovaries. Underneath this layer is a dense connective tissue capsule, the tunica albuginea. The substance of the ovaries is distinctly divided into an outer cortex and an inner medulla. The cortex appears more dense and granular due to the presence of numerous ovarian follicles in various stages of development. Each of the follicles contains an oocyte, a female germ cell. The medulla is a loose connective tissue with abundant blood vessels, lymphatic vessels, and nerve fibres.
• Ovary – The primary female reproductive organs, or gonads, are the two ovaries. Each ovary is a solid, ovoid structure about the size and shapes of an almond, about 3.5 cm in length, 2 cm wide, and 1 cm thick. The ovaries are located in shallow depressions, called ovarian fossae, one on each side of the uterus, in the lateral walls of the pelvic cavity. They are held loosely in place by peritoneal ligaments.
• Oviduct – An oviduct is a tube that links the ovary to the uterus; allowing the ovulated oocyte travel down, in order to become0 fertilised by the sperm present in the female fallopian tube.
• Uterus – The uterus is a muscular organ that receives the fertilized oocyte and provides an appropriate environment for the developing fetus. Before the first pregnancy, the uterus is about the size and shape of a pear, with the narrow portion directed inferiorly. After childbirth, the uterus is usually larger, and then regresses after menopause.
• Vagina – The vagina is a fibro muscular tube, about 10 cm long that extends from the cervix of the uterus to the outside. It is located between the rectum and the urinary bladder. Because the vagina is tilted posterior as it ascends and the cervix is tilted interiorly, the cervix projects into the vagina at nearly a right angle. The vagina serves as a passageway for menstrual flow, receives the erect penis during intercourse, and is the birth canal during childbirth.
• External genitalia – The external genitalia are the accessory structures of the female reproductive system that are external to the vagina. They are also referred to as the vulva or pudendum. The external genitalia include the labia majora, mons pubis, labia minora, clitoris, and glands within the vestibule. The clitoris is an erectile organ, similar to the male penis that responds to sexual stimulation. Posterior to the clitoris, the urethra, vagina, par urethral glands and greater vestibular glands open into the vestibule.
• Mammary Glands – Functionally, the mammary glands produce milk; structurally, they are modified sweat glands. Mammary glands, which are located in the breast overlying the pectoralis major muscles, are present in both sexes, but usually are functional only in the female. Prolactin from the anterior pituitary stimulates the production of milk within the glandular tissue, and oxytocin causes the ejection of milk from the glands.
Female sex cells, or gametes, develop in the ovaries by a form of meiosis called oogenesis. The sequence of events in oogenesis is similar to the sequence in spermatogenesis, but the timing and final result is different. Early in fetal development, primitive germ cells in the ovaries differentiate into oogonia. These divide rapidly to form thousands of cells, still called oogonia, which have a full complement of 46 (23 pairs) chromosomes. Oogonia then enter a growth phase, enlarge, and become primary oocyte. The diploid (46 chromosomes) primary oocyte replicates their DNA and begins the first meiotic division, but the process stops in prophase and the cells remain in this suspended state until puberty. Many of the primary oocyte degenerates before birth, but even with this decline, the two ovaries together contain approximately 700,000 oocyte at birth. This is the lifetime supply, and no more will develop. This is quite different than the male in which spermatogonia and primary spermatocytes continue to be produced throughout the reproductive lifetime. By puberty the number of primary oocyte has further declined to about 400,000.
Beginning at puberty, under the influence of follicle-stimulating hormone, several primary oocyte start to grow again each month. One of the primary oocyte seems to outgrow the others and it resumes meiosis I. The other cells degenerate. The large cell undergoes an unequal division so that nearly all the cytoplasm, organelles, and half the chromosomes go to one cell, which becomes a secondary oocyte. The remaining half of the chromosomes go to a smaller cell called the first polar body. The secondary oocyte begins the second meiotic division, but the process stops in metaphase. At this point ovulation occurs. If fertilization occurs, meiosis II continues. Again this is an unequal division with all of the cytoplasm going to the ovum, which has 23 single-stranded chromosomes. The smaller cell from this division is a second polar body. The first polar body also usually divides in meiosis I to produce two even smaller polar bodies. If fertilization does not occur, the second meiotic division is never completed and the secondary oocyte degenerates. Here again there are obvious differences between the male and female. In spermatogenesis, four functional sperm develop from each primary spermatocytes. In oogenesis, only one functional fertilizable cell develops from a primary oocyte. The other three cells are polar bodies and they degenerate.
Female sex cells, or gametes, create in the ovaries by a type of meiosis called oogenesis. The arrangement of occasions in oogenesis is like the succession in spermatogenesis, however the planning and last outcome is extraordinary. Ahead of schedule in fetal advancement, crude germ cells in the ovaries separate into oogonia. These gap quickly to frame a huge number of cells, still called oogonia, which have a full supplement of 46 (23 sets) chromosomes. Oogonia at that point enter a development stage, broaden, and end up essential oocyte. The diploid (46 chromosomes) essential oocyte repeats their DNA and starts the primary meiotic division, however the procedure stops in prophase and the cells stay in this suspended state until adolescence. A considerable lot of the essential oocyte deteriorates before birth, yet even with this decay, the two ovaries together contain around 700,000 oocyte during childbirth. This is the lifetime supply, and no more will create. This is very unique in relation to the male in which spermatogonia and essential spermatocytes keep on being delivered all through the conceptive lifetime. By pubescence the quantity of essential oocyte has additionally declined to around 400,000.
Starting at adolescence, affected by follicle-empowering hormone, a few essential oocyte begin to become again each month
M5. Report on the common tests performed to measure fertility.
Causes of Infertility in Males
Infertility in men are caused by poor quality semen, as fluids containing the sperm that’s ejaculated during sex. An abnormal semen could include: a lack of sperm, sperm that aren’t moving properly and an abnormal sperm. When a testicle is b
Sperm transport problems are found in one in every five infertile men, including those who had a vasectomy. Therefore, the blockages in the tube leads the sperm away from the testes the penis, which causes a lack of sperm in the ejaculated semen.
However, there are other less common causes of infertility which includes sexual problems that affects the semen being able to enter the woman’s vagina for fertilisation to take place. Other common causes of infertility are low levels of hormones made in the pituitary gland which acts on the testes, and sperm antibodies which are found in some men who are infertile. Sperm antibodies may not affect a chance of a pregnancy but in some male’s sperm antibodies reduces fertility.
Causes of Infertility in Females
The most common causes of infertility in females are ovulation, damage to the fallopian tubes or the uterus, or even problems with the cervix. However, age can contribute in female infertility.
Female infertility that may affect the woman’s ability is to be able to conceive naturally is: smoking, stress, alcohol, being overweight and underweight and also sexually transmitted infections.
In ovulation disorder, they affect the woman’s ability to conceive naturally, which is meant that when a woman ovulates infrequently, or not at all.
Tests for Men
Male fertility requires that the testicles produce enough healthy sperm, which the sperm ejaculates effectively into the woman’s vagina as it travels to the egg. However, for the male infertility attempts to determine whether any of the processes are impaired.
A doctor will ask for one or more semen specimens. Semen can be obtained by masturbating or interrupting an intercourse and ejaculating semen into a clear container. The lab analyses your semen specimen. Also semen can also be tested in some cases through urinating. However, these samples can be collected at home and kept at room temperature, and get the sample to the doctor within an hour. Your doctor may ask you not to masturbate for 2 to 5 days before your test, in order to make sure your sperm count is as high as possible. If you do avoid ejaculation for about 2 weeks than the sample may have sperm that are less active.
When drinking alcohol before semen analysis, you should be required to tell your doctor about it and also any medications you’ve taken as well. Finally, when using lubricants to collect your semen sample his can affect how easily the sperm moves around.
Doctors may also require you to provide with more than one sample over a period of three months to ensure that they can get accurate results.
Sperm Count -a normal sperm count is between 15 million and 200 million sperm millimetre of semen. As your sperm count would usually be considered as low if you have below that range.
Sperm motility -the doctor will generally look at the numbers of sperms that actually move. About 50% or more of your sperm sample should be active.
Morphology -the sperms size and shape matters, as it could affect their ability to fertilise an egg. Potentially, the doctor would be looking for the volume, chemical makeup, liquefaction time and your fructose level.
• Volume- the doctor notes down the amount of semen that you’re able to provide for your sample. However, a normal amount is 2.5 millimetres. If the sample is less than 2.5 millimetres than it could mean the seminal vesicles isn’t making enough fluid or due to it being blocked. This could also mean that there could be issue with your prostate.
• Chemical Makeup-the pH level measure the acidity of your semen. Therefore the normal pH level is between7.1 to 8.0. Having a low pH could mean that you may have an acidic semen, as for having a high pH level this could mean that it’s alkaline. However, having an abnormal pH can affect the health of your sperm and how well it moves.
• Liquefaction- time- when ejaculating having a thick semen is normal. The liquefaction time looks at how long it would take before it becomes liquid, which should take about 20 minutes, not any longer. If it does take any longer than 20 minutes or doesn’t become a liquid this would mean that there could be an issue.
• Fructose level-when the doctor doesn’t find any sperm in our semen analysis, than the doctor will try to check it for seminal fructose, which are produced by your seminal vesicles. At low levels or no fructose would mean that there could be an obstruction.
The process of hormone testing is through having a blood test in order to determine the level of testosterone and other male hormones.
Chlamydia is a bacteria, which requires the doctor to check chlamydia screening test to see whether their patient has the infection or not. They recommend people take yearly test due to the rate of chlamydia being in the highest group. However, for pregnant woman they should be tested for chlamydia during their first ever prenatal exam.
Tests chlamydia for men usually requires them to take a urine test. A sample of urine is analysed in the laboratory to indicate the presence of the infection.
Test for Women
Fertility for women mostly would rely on the ovaries releasing healthy eggs. The female’s reproductive tract must allow an egg to pass into the fallopian tube so it could join with the sperm for fertilisation. As the fertilised egg ravels towards the uterus and then implant in the lining. However, the test for female infertility it to determine the process that are impaired.
Transvaginal Ultrasound scan
An ultrasound test uses the high frequency to create an image of the internal organs. These imaging test allow to see the abnormalities that occur, in order for the doctor to help diagnose these conditions. However, a transvaginal ultrasound is a pelvic ultrasound used by the doctors to examine the female’s reproductive organs such as the uterus, fallopian tubes, ovaries, cervix and the vagina. However, the transvaginal ultrasound can even be used in cases such as infertility. Your doctor might recommend if you get the procedure done during pregnancy to identify any abnormalities that occur. A transvaginal ultrasound scan can help diagnose conditions such as:
• Ectopic pregnancy
These scan can help check the blockages that are in the fallopian tubes, which could allow the egg to stop from travelling along the tubes and into the womb. About one-third of woman may have this issue, of a blockage in the fallopian tube or damaged fallopian tube.
Female Hormone Testing
The level of hormone in a woman’s blood are al almost linked to ovulation, as when the ovaries release an egg into the fallopian tubes. If hormone imbalances are caused in a female this would mean that there might be an ovulation issue. This is why a doctor needs a sample of blood to test a female’s hormonal level to determine whether this is happening or not. When a female have no periods or irregular periods, this could possibly show signs of ovulation problems, as the common issue of this symptom could be polycystic ovary syndrome.
Progesterone is produced primarily by the corpus luteum of the ovary in the menstruating women and lesser extent by the adrenal cortex.
In the 6 week period of pregnancy, the placenta will eventually become the major producer of progesterone.
The major functions
Progesterone test is carried out by the Chemiluminescent Micro particle. As blood is collected by the Phlebotomist nurse.
As for females test for chlamydia requires them to take a swab test. The doctor would take a swab of the discharged cervix for the culture or antigen testing for chlamydia. Women’s prefer to swab their vagina themselves, which are as diagnostic as the doctor obtained swabs.
Urinary Dip Sticks
Doctors tend to use urinary dip sticks on female patients, which are widely used for ovulation detection. Testing urine are also used for screening people for drug use and for a women is pregnant. Doctors can tell from a test, by the way the urine looks and smells. An example a dark urine can symbolise dehydration; a cloudy appearance can show infection, and if the urine shows a reddish colour then there may be blood in the urine, also if a urine has a sweet smell, this can be a sign of diabetes.
X-ray of the Fallopian Tubes (Hysterosalpingogram)
Hysterosalpingogram is a procedure that uses an x-ray to look at the fallopian tube and uterus. The doctor would generally do a procedure after your period but before you ovulate, due it’s less likely you’ll pregnant during this time. This would happen at the first half of the cycle, roughly between day 1 and day 14.
• Positive and Negative effect in Hormonal treatments to improve fertility in females
If a women has infertility issues then a doctor will help by prescribing the patient with medicine in order to help the patient get pregnant. These medicines are fertility drugs, which helps causing the body to release hormones which regulates ovulation; the release of an egg from the ovary.
IVF (in vitro fertilisation) are methods in which females use to help increase their chances of getting pregnant, but using a fertility drug is also vital as it is part of the treatment.
The possible side effects of using the fertility drugs are is generally mild, but it can include hot flashes, blurred vision, nausea, bloating and headaches.
• Possible ways of increasing the chances of getting pregnant
Increasing the chances of getting pregnant would require that both partners are in good health. Alternating your lifestyle can help improve the chances of getting pregnant, also having a healthy pregnancy as well.
However, if there are medical conditions such as diabetes, asthma, obesity and other problems can affect your pregnancy. Being overweight or underweight can have an effect on your chances of conceiving. Having too much fat can also make periods irregular or even stop them completely. This is why having a healthy BMI is important. When it comes to alcohol and smoking this can have a great impact in your chances of conceiving, as for smoking reduces fertility in women.
D4. Evaluate data concerning the levels of sex hormones at different times in the menstrual cycle in relation to fertility
The Menstrual Cycle – Females
The menstrual cycle lasts up to 28 days, in which a woman’s uterus prepares for a fertilised egg to settle and grow into a baby. As for the human fertility is regulated by four hormones (luteinizing hormone, follicle-stimulating hormone, and the female sex hormones estrogen and progesterone) which are produced by the pituitary gland, promoting ovulation and to stimulate the ovaries, In order to produce estrogen and progesterone, which are involved in specialised cells. The chromosomes carry genetic information for the formation of offspring especially the gender. Chromosomes are able to pass the genetic disorder. However, the fertility treatment is used to help treat the difficulties with the conception. These events are divided into three phases, these phases are:
• The Follicular Phase (before release of the egg)
• The Ovulatory Phase (egg release)
• The Luteal Phase (after egg release)
When the follicular phase begins, the levels of estrogen and progesterone become low, as the menstrual cycle will first begin to discharge blood from the uterus. From day 1 to about day 5 the top layers of the thickened lining of the uterus, also known as endometrium, which breaks down and are shed, and the menstrual bleeding occurs. During this time the follicle-stimulating hormone levels will increase slightly, as stimulating the development of several follicles in the ovaries. Each of the follicular contains egg. Later in this phase, the follicular-stimulating phase level decreases, as only one of the follicle will develop and eventually produces oestrogen.
This phase begins when the level of luteinizing hormone surges. The luteinizing hormone stimulates the dominant follicle to bulge from the surface of the ovary and then finalise its rupture, releasing the egg. The level of follicle-stimulating hormone increases to a lesser degree. However, the function of the increase in follicle-stimulating hormone is not understood.
The ovulatory phase usually lasts 16 to 32 hours. It ends when the egg is released, about 10 to 12 hours after the surge in the level of luteinizing hormone. The egg can be fertilized for only up to about 12 hours after its release.
The surge in luteinizing hormone can be detected by measuring the level of this hormone in urine. This measurement can be used to determine when women are fertile. Fertilization is more likely when sperm are present in the reproductive tract before the egg is released. Most pregnancies occur when intercourse occurs within 3 days before ovulation.
Around the time of ovulation, some women feel a dull pain on one side of the lower abdomen. This pain is known as mittelschmerz (literally, middle pain). The pain may last for a few minutes to a few hours. The pain is usually felt on the same side as the ovary that released the egg, but the precise cause of the pain is unknown. The pain may precede or follow the rupture of the follicle and may not occur in all cycles.
Egg release does not alternate between the two ovaries and appears to be random. If one ovary is removed, the remaining ovary releases an egg every month.
This phase begins after ovulation. It lasts about 14 days (unless fertilization occurs) and ends just before a menstrual period. In this phase, the ruptured follicle closes after releasing the egg and forms a structure called a corpus luteum, which produces increasing quantities of progesterone. The progesterone produced by the corpus luteum prepares the uterus in case an embryo is implanted. The progesterone causes the endometrium to thicken, filling with fluids and nutrients to nourish a potential embryo. Progesterone causes the mucus in the cervix to thicken, so that sperm or bacteria are less likely to enter the uterus. Progesterone also causes body temperature to increase slightly during the luteal phase and remain elevated until a menstrual period begins. This increase in temperature can be used to estimate whether ovulation has occurred. During most of the luteal phase, the estrogen level is high. Estrogen also stimulates the endometrium to thicken.
The increase in estrogen and progesterone levels causes milk ducts in the breasts to widen (dilate). As a result, the breasts may swell and become tender.
If the egg is not fertilized or if the fertilized egg does not implant, the corpus luteum degenerates after 14 days, levels of estrogen and progesterone decrease, and a new menstrual cycle begins.
If the embryo is implanted, the cells around the developing embryo begin to produce a hormone called human chorionic gonadotropin. This hormone maintains the corpus luteum, which continues to produce progesterone, until the growing foetus can produce its own hormones. Pregnancy tests are based on detecting an increase in the human chorionic gonadotropin level.
The Hormone Cycle – Males
Male’s hormones cycle are different than female’s hormone cycle because males have a daily hormone cycle. Female’s produce testosterone as well as male’s, as their menstrual cycle is governed by hormones known as estrogen and progesterone. As for male’s they produce estrogen and progesterone; making their dominant hormone is testosterone.
In the morning Men’s testosterone levels is at its peak, this makes them more attentive, energetic, talkative, aggressive and competitive. For men mornings is the best time to participate or focus on tasks that are needed to be completed.
In the afternoon, the testosterone levels wanes, as its still present in significant amounts. At this time of the day the men are much calmer in the afternoon in comparison to mornings, but they are still happy and upbeat. In the afternoon they become more creative and open to discussion in this stage.
In the evening the testosterone is at its lowest, this changes the men’s mood making them feel tired. At this stage men become quite passive