The physiological significance of timing of fertilization, erogenous zones, and the refractory period after sexual intercourse.

> 70. **What is fertilization? When is it most likely to occur?**

>

Fertilization is the process by which a sperm and an egg unite, a process that results in the formation of a mature egg.

After being released from the ovary, the sperm travels through the fimbriae of the fallopian tube to the ampulla. If sperm is present at this point...

It enters the body, passes through the cervix and uterus, reaches the fallopian tube, meets the egg, and fertilizes.

A new cell is synthesized-a fertilized egg. We call this process fertilization.

>

The fertilized egg, or zygote, undergoes a 3-4 day "honeymoon" journey after fertilization.

It takes time for the endometrium to travel from the fallopian tubes to the uterus. At this point, the uterine lining is affected by estrogen and progesterone.

Under the influence of elements, and through careful arrangement, it resembles a warm and comfortable palace. (Fertilization)

After cleavage, the egg develops into a human blastocyst, which secretes a protein-degrading enzyme that invades...

> It erodes the uterine lining, allowing a fertilized egg to implant therein, a process medically known as "implantation," which leads to pregnancy.

>

While men can continuously produce sperm during their reproductive years, women produce sperm regularly, month by month.

Ovulation occurs once. Ovulation usually occurs 12-16 days before the next menstrual period. Sperm ejaculation...

The female reproductive tract retains its fertilization capacity for 1-2 days after ovulation.

Life expectancy is generally about 24 ± 6 hours, and the average time for fertilization after intercourse is 12–14 hours.

> 24 hours. Therefore, intercourse should only be performed 1-2 days before or after ovulation in the middle of the menstrual cycle.

There is a possibility of pregnancy. If either sperm or egg has lost its fertility by the time they meet...

If a woman loses her fertilizing ability, she cannot conceive. However, in real life, we can also see cases where women conceive on the [number]th day of their menstrual cycle.

Women who conceived through intercourse within 7 days of intercourse. This is likely due to additional ovulation caused by intercourse.

As for whether the survival time of sperm can be unexpectedly extended, it is not yet fully understood.

>

After the egg is released from the ovary, it enters the fallopian tube approximately 8-10 minutes later.

The sperm will remain at the junction of the fallopian tube and the isthmus (amula of the fallopian tube), where fertilization will occur if sperm is encountered.

>

> 71. **What is the so-called erogenous zone?**

>

Certain parts of the human body have special sensitivities; once these parts are affected...

Stimulation from the opposite sex can arouse sexual desire, hence it is called a "sexual erogenous zone," or simply a...

The "erogenous zone" or "sexual erogenous zone" is significant for receiving stimulation from the opposite sex.

> Enhance sexual arousal and facilitate sexual behavior.

>

Modern sexology classifies human erogenous zones into three areas: A, B, and C, according to their intensity.

Area A is the most sexually sensitive area, specifically the outer...

> The genital area and surrounding areas, such as the buttocks near the vulva, the inner thighs, etc., especially

The penis and other parts of the penis are the contact points for male-female sexual intercourse, and their sexual sensitivity is particularly pronounced.

Area B, specifically the breasts, is less sexually sensitive than area A. This applies to both men and women.

In women, all breasts can become sexually sensitive, with the nipples being the most prominent area.

Under stimulation, a certain degree of congestion will occur, causing the nipples to harden and become erect. Secondly, the nipples...

> Dizziness can also trigger sexual desire. Area C is slightly less sexually sensitive than area B.

> Lips, tongue, cheeks, neck, etc., with the lips and tongue being the center of this area.

>

So, why are these areas sexually sensitive? What's the reason behind it?

The mystery remains unclear to this day. However, there are several explanations: One is...

> Symbols, such as the external genitalia, represent male characteristics and therefore naturally possess...

The ability to strongly evoke emotions. Secondly, the focal point of emotional connection, such as the lips and tongue.

These are often the parts of the body that couples like to touch the most. Thirdly, there are neuroendocrine connections...

The nerve distribution in a given area is closely related to the parts of the central nervous system that control activity.

> Cutting and stimulating these areas can easily increase the production of sex hormones. Obviously...

As can be seen, appropriately and moderately stimulating erogenous zones can not only arouse sexual desire, but also...

This can lead to heightened libido, so erogenous zones are indeed very important in normal sexual activity.

> This is an important part. To achieve a fulfilling sex life, the role of erogenous zones cannot be ignored or simplified.

>

> 72. **What is the refractory period after sexual intercourse?**

>

As people enter middle age, their children grow up and are no longer a burden like they were in infancy.

> As men age, a wife's libido may increase, which is normal. Most women experience a peak in sexual desire.

> This period also falls within this age range. At this time, as a husband, you are unable to satisfy your wife's needs.

Seeking this is a perfectly normal occurrence; it's just that we hadn't noticed it before. This is unique to men.

This is a physiological phenomenon. After one ejaculation, a man is unable to immediately engage in a second ejaculation.

Ejaculation, medically termed the "refractory period," refers to the time after ejaculation occurs, when the penis has ejaculated.

There must be a relaxation phase before a second orgasm occurs, during which even...

Even with sufficient sexual stimulation, it will not arouse sexual desire or impulse.

>

The refractory period after sexual intercourse is quite pronounced in middle-aged men. Men experience a significant refractory period after sexual intercourse.

During orgasm, the ejaculatory ducts, seminal vesicles, prostate, and urethral muscles contract rhythmically and strongly.

Once contraction is complete, these organs immediately transition from a state of tension to a state of relaxation. Additionally...

In addition, the stimulation of strong sexual impulses causes high tension in both the nervous and endocrine systems;

Once the impulse subsides, their activity immediately shifts from excitement to inhibition. This is because male sexual...

Impulses arise quickly and subside just as fast, so this tension and relaxation, excitement and...

Inhibition becomes highly volatile. Therefore, the relaxation and inhibition phases coincide with periods of fatigue and...

The necessary rest period for fatigue is the origin of the refractory period.

>

The refractory period in such men can last from a few minutes to several hours.

The length of the refractory period varies from person to person, and even for the same person, it can vary at different times.

The length of the refractory period also varies greatly. Generally speaking, the male refractory period increases with age.

The refractory period is prolonged with the increase of time; for example, it is short in youth and middle age, and long in old age.

> Length. This is an important sexual physiological phenomenon that distinguishes men from women. Therefore, when

Once you understand this basic physiological fact, you no longer need to worry and doubt whether you have a problem with your sexual function.

>

> 73. **What is the relationship between men and androgens?**

>

The testes secrete male hormones, so some people also call androgens "male hormones."

> Androgens. Although both men and women have androgens, men are the most representative. Its main...

The main function is to stimulate the male secondary sexual organs to develop and mature, maintain normal libido, and promote...

> Promotes sperm maturation, facilitates protein synthesis and skeletal muscle growth, and enables muscle...

> Well-developed muscles; inhibits the increase of body fat, stimulates the production of red blood cells and the growth of long bones.

Growth; promotes the formation of secondary sexual characteristics. For example, in boys, the Adam's apple begins to enlarge around age 11-12.

> And gradually becomes more obvious, while the vocal cords thicken and widen, resulting in a deep and resonant voice; 12

Pubic hair begins to appear around age 13 and gradually becomes thicker and coarser; around age 14-15...

> Appearance of armpit hair, breast swelling, and darkening of nipples; facial hair begins to grow around 16-17 years old.

Skin becomes rough, the subcutaneous fat layer thins, and sebaceous glands secrete excessively, leading to acne.

Acne (also known as pimples); body hair becomes coarse, short, and dark, with longer chest hair.

The forehead features specific indentations at the temples where the hairline recedes. All of these phenomena are characteristic of androgynous men.

This is caused by the effects of sex hormones. Insufficient secretion of male hormones not only affects human fertility...

> During puberty, sexual function declines, and some women may lack male virility.

> Characteristics. Scientists believe that although endocrine glands produce hormones,

However, it is also controlled by the brain's central nervous system. A person's emotions can stimulate the parasympathetic nervous system.

The nervous and endocrine systems, through feedback, enhance the secretion of the endocrine system, promoting...

Improves blood circulation, enhances breathing rhythm, raises body temperature, and accelerates the body's metabolism.

> And the formation of hormones, which makes young men handsome and strong, with smooth and shiny skin.

> Elasticity, bright and piercing eyes, vibrant spirit, and masculine beauty. (Chinese)

As men age, their secretion of male hormones gradually decreases, and their sexual function gradually declines, affecting various systems.

The metabolic function of male hormones is also declining. Therefore, the normal secretion of male hormones is essential for vitamin D.

Maintaining a normal sex life, preserving youthful vitality, and keeping youth alive are all very important for men.