Wk 7a Male reproductive system

What are the main components of the male reproductive system?

The main components are the external genitalia (penis and scrotum) and internal genitalia (testes, epididymis, ductus deferens, seminal vesicles, prostate gland, and urethra).

Where is sperm produced in the male reproductive system?

Sperm is produced in the seminiferous tubules, the tubules are within the lobules which are actually located in the testes

What temperature is optimal for sperm production?

Sperm production requires a temperature of about 34-35 degrees Celsius, lower than the body's core temperature.

What is the function of the epididymis?

The epididymis is where sperm mature and are stored prior to ejaculation. epididymis also acts as a storage site for sperm that were not ejaculated

What is the ductus deferens also known as?

The ductus deferens is also known as the vas deferens.

What do the seminal vesicles secrete?

The seminal vesicles secrete a thick alkaline fluid that contains fructose and prostaglandins.

What is the role of the prostate gland?

The prostate gland secretes a milky fluid (prostatic fluid) that contains citric acid, seminal plasmin, and prostate-specific antigen. to nourish sperm

What does the bulbourethral gland produce?

The bulbourethral gland produces a clear mucus for lubrication of the urethra to protect sperm and neutralise acidic urine residue. they are ocated alongside the membranous urethra, but they "drain" into the bulbous urethra.

What is semen composed of?

Semen is composed of sperm (10%), seminal fluid from the seminal vesicles (60%), prostatic fluid (30%) from the prostate gland, and urethral mucus majorly from bulbourethral and other urethral glands.

How many sperm are typically present in an ejaculate?

Between 80 million to 500 million sperm are present in an ejaculate fluid expelled from the external urethral meatus/orifice) - opening at the base of the penis

What hormone stimulates testosterone production in males?

Luteinizing hormone (LH) stimulates testosterone production in males.

What is the function of the sustentacular cells in the testes?

Sustentacular cells (Sertoli cells) support developing sperm and produce androgen-binding protein which helps in maintaining high testosterone levels in the seminiferous tubules, they nourish sperm

What type of nerve supply is responsible for erection?

The parasympathetic nervous system is responsible for causing an erection . NO activate an enzyme as it moves into smooth muscle - This enzyme creates a molecule called cGMP. It is the cGMP,Arterial Relaxation: The walls of the penile arteries relax and widen (vasodilation), allowing a massive surge of blood to flow in.

• Trabecular Relaxation: The smooth muscle within the corpus cavernosum (the erectile tissue) also relaxes, creating space for that blood to fill the "spongy" gaps. corpus spongiosium also recevees bllod and its mucle relax but it cannot be to hard If the corpus spongiosum became as rigid as the cavernosa it would shut the urethra. ooth muscle relaxation and increased blood flow to the penis). erectile tissue fills with blood and expands, it actually compresses the veins that normally drain blood away from the penis.PDE5 eventually breaks down that cGMP to stop the process and entrapment and allow the penis to become flaccid again.

What happens to blood flow during an erection?

Blood flow increases significantly, filling the erectile bodies and compressing the veins that usually drain blood away. smooth muscles relax. erectile bodies are the specialized tissues within the penis that fill with blood to create an erection,-they are : Two Corpora Cavernosa and One Corpus Spongiosum:

What role do the symphonic and pudendal nerves play in ejaculation?

The sympathetic nerves trigger ejaculation, while the pudendal nerve helps stimulate muscular contraction for emission and expulsion.

What is the refractory period in males?

The refractory period is the time following ejaculation during which a man cannot achieve another erection.

Where is sperm stored after production?

Sperm is stored and mature in the epididymis after production in the testes. sperm is also temporarily stored in vas deferens AKA ductus deferens

What is the function of the tunica albuginea in the testes?

The tunica albuginea is a thick fibrous layer that supports the testis and divides it into lobules about 200 - 400 in one testis, each lobule with up to 1 to 4 high coiled seminiferous tubule where sperm is produced . they provide structural intergrity and compartmentalisation of testisThis layer also helps facilitate the formation of sperm by containing seminiferous tubules.  . Efferent Ductules transport sperm from the rete testis (collection point of all st) seminiferous tubules, out of tunica albuginea then out of testes to the epididymis.

What is the relationship between spermatogonia and sperm production?

Spermatogonia are the initial germ cells which divide and differentiate into sperm cells.

What is spermiogenesis?

Spermiogenesis is the process where spermatids undergo morphological changes to become mature spermatozoa (sperm).

Multiplication	Spermatogonia	These are the "stem/germ cells." They sit at the outer wall of the tubule and divide to create a constant supply of new cells.
2. Division (Meiosis)	Spermatocytes	The cells move toward the centre. They divide their DNA in half (from 46 chromosomes to 23) so that when they meet an egg, the baby has the right amount.
3. Transformation	Spermatids	The cells are now round blobs with half the DNA. They undergo Spermiogenesis (the morphological change).

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The Morphological Change (Spermiogenesis)

This is where the Spermatid "remodels" itself into a Spermatozoon (singular sperm). During this specific phase:

1. The Head forms: DNA is packed tightly into a tiny "bullet" shape.

2. The Acrosome develops: A cap containing enzymes grows on the head (to help break into the egg).

3. The Tail (Flagellum) grows: A long tail forms for swimming.

4. Midpiece formation: Mitochondria (the "engines") wrap around the base of the tail to provide power.

5. Shedding: The cell gets rid of all its "luggage" (excess cytoplasm) to become light and aerodynamic.

Final Result- spermatozoon- singular (spermatozoa -plural)

How long does it take for sperm to travel from production to ejaculation?

It takes about two weeks for sperm to travel from production to ejaculation.

Where does fertilization occur?

Fertilization occurs in the uterine tubes (fallopian tubes). specifically the ampulla region in the fallopian tubes

What prevents urine from being expelled during ejaculation?

The internal urethral sphincter closes to prevent urine from being expelled.

What does progesterone stimulate in males?

Progesterone is not primarily present in males; they mainly produce testosterone.

What is the pathway of sperm during ejaculation?

Sperm travels from the epididymis through the ductus deferens connect to the ductus defences from its tail . Fluid from the seminal vesicle is added right at the junction( where ampulla of ductus deferens and seminal vesicle merge) that forms the start of the ejaculatory duct, creating the fluid-sperm mixture. This mixture then passes through the ejaculatory duct (which runs through the prostate gland), receives additional fluid from the prostate gland, and ultimately travels through the urethra.

What anatomical structure houses the testes?

The scrotum houses the testes.

How do the left and right testicular veins drain?

The right testicular vein drains directly into the inferior vena cava, while the left drains into the left renal vein before the inferior vena cava.

What anatomical landmark separates the left and right scrotal sacs?

The raphe separates the left and right scrotal sacs. scrotal rapheThe raphe is a narrow ridge of tissue that runs along the midline of the symmetrical scrotum,

What are the three layers surrounding the testis and their roles?

The three layers are the tunica vasculosa, tunica vaginalis, and tunica albuginea. the three tissues membrane act as protective, supportive, and nourishing membranes. The tunica vaginalis (outermost) reduces friction, the tunica albuginea (middle) provides structural integrity and compartmentalization, and the tunica vasculosa (innermost) supplies essential nutrients and oxygen to the testicular tissue.

What cell type produces testosterone?

Leydig cells (interstitial cells) produce testosterone. they are located in interstitial connective tissue between semiferous tubules in the testes.

What role do prostaglandins play in reproduction?

Prostaglandins produced by seminal vesicle adding to the semen during ejaculation help increase sperm motility and function. including aiding in the movement of sperm through the female reproductive tract, which is crucial for successful fertilization. they relax cervical mucus for sperm pentration and contract smooth muscle uterus and fallopian transport sperm to ward egg, they also suppress female immune responseto prevent rejection of sperm

What is the structure of the penis that surrounds the urethra called?

The corpus spongiosum surrounds the urethra in the penis.

What can cause a decrease in sperm count in sexually active men?

Frequent ejaculation can lead to a dilution effect, decreasing sperm count.

What is the role of the cremaster muscle and dartos in cold?

The cremaster muscle raises and lowers the testes for temperature regulation.ensure they remain at an optimal temperature for sperm production(spermatogenesis) maintain a constant temperature of roughly 33°C to 34°, prevent overheat and too cold. cremaster contract when it is too cold pull testes to the body to absorb heat. dartos contracts in the cold to wrinkle the scrotal skin,

What is the function of the dartos muscle?

The dartos muscle helps to elevate and lower the scrotum in response to temperature. when it is cold it wrinkles the skin Because the skin is getting tighter and pulling inward, this naturally causes the scrotum and the testes inside it to be elevated and held closer to the body

What is the significance of erectile tissue within the penis?

Erectile tissue allows the penis to engorge with blood, resulting in an erection.

Where does sperm maturation mainly occur?

Sperm maturation mainly occurs in the epididymis.

What is the clinical term for the process of releasing sperm during sexual climax?

The clinical term is ejaculation.

What are the two types of nerves involved in the process of erection and ejaculation, respectively?

Parasympathetic nerves are involved in erection, while sympathetic nerves are involved in ejaculation.

How does the body respond to cold temperatures to protect the testes?

The dartos muscle contracts to elevate the scrotum and maintain temperature.

What happens to unused sperm in the epididymis?

Unused sperm are reabsorbed by the epithelial cells lining the duct of the epididymis.

How does the sympathetic nervous system contribute to the sexual response?

The sympathetic nervous system controls ejaculation and the closing of the internal urethral sphincter.

What is the male equivalent of the female ovary?

The testes (plural)are the male equivalent of the female ovary.

What is the average weight of a human testis?

The average weight of a human testis is about 10 to 12 grams.

What are the three columns of erectile tissue in the penis?

The three columns of erectile tissue in the penis are two corpora cavernosa and one corpus spongiosum.

How is the temperature of the testes regulated within the scrotum?

The testes are regulated by the cremaster muscle and dartos muscle, which raise or lower the testes closer to or further from the body, and by the pampiniform plexus, which cools arterial blood entering the testes.

What is the specific function of nitric oxide (NO) in achieving a penile erection?

Nitric oxide is released by parasympathetic nerve endings, causing smooth muscle relaxation in the arterial walls of the penis, leading to vasodilation and increased blood flow into the erectile tissues.

What are the two distinct phases of ejaculation?

The two phases are emission, where semen moves into the urethra, and expulsion, where semen is ejected from the urethra.

What is the ejaculatory duct formed by?

The ejaculatory duct is formed by the convergence of the ampulla of the ductus deferens and the seminal vesicle duct.

Describe the 'resolution phase' following male orgasm.

The resolution phase is a period of relaxation where sympatheticThe sympathetic nerves release norepinephrine, which causes the smooth muscles in the arterial walls of penis to contract (vasoconstriction). This restricts the "inflow" of blood. stimulation causes vasoconstriction of penile arteries, decreasing blood flow, and the penis returns to its flaccid state. (detumscence)This phase involves a decrease in heart rate and a feeling of relaxation as the body transitions to a resting state.