WEEK 4: ANATOMY OF THE MALE REPRODUCTIVE SYSTEM

Question 1

State the 2 main division of the male reproductive system

Answer 1

*internal genitalia
*external genitalia

Question 2

What are the 3 main parts of the penis?

Answer 2

*The shaft/ body
*The glans
*the root

Question 3

What are the 3 erectile bodies found in the shaft of the penis and their function?

Answer 3

*2 corpus cavernosum: fuse in the median plane except posteriorly to form crura of the penis
*1 corpus spongoisum :contains spongy urethra

Question 4

Divide the parts of the male reproductive system as internal and external organs

Answer 4

INTERNAL: testes, epididymis, vas deferens, seminal vesicle, ejaculatory ducts, prostate gland, urethra , bulbo-urethral gland

EXTERNAL: penis and scrotum

Question 5

What is the largest accessory gland of the male reproductive system?

Answer 5

Prostate gland

Question 6

What makes up the ejaculatory duct?

Answer 6

*Joining together of the seminal vesicle duct and vas deferens
*These ducts are formed by the fusion of the vas deferens and the seminal vesicles duct

Question 7

What suspends the testes from the scrotum?

Answer 7

spermatic cord

Question 8

Name the cells in the testes that produce male sex hormones.
Where are they located?

Answer 8

*Interstitial cells (cells of Leydig), which produce male sex hormones,
*In the interstitial tissue between the seminiferous tubules

Question 9

Name the 3 structures which are found at the root of the penis

Answer 9

*Right crura
*Left crura
*bulb of the penis

Question 10

Which part of the penis formed by the distal expansion of the corpus spongiosum.

Answer 10

The glans (head)

Question 11

What is another name for foreskin?

Answer 11

prepuce

Question 12

State the muscles of the scrotum that in the subcutaneous tissue contract to give the scrotum its wrinkled appearance. When these fibers are relaxed, the scrotum is smooth

Answer 12

Dartos muscle

Question 13

What are functions of the cremaster muscles?

Answer 13

controls the position of the scrotum and testes. When it is cold or a man is sexually aroused, this muscle contracts to pull the testes closer to the body for warmth.

Question 14

State the two main function of the penis

Answer 14

*Micturition: urinating
*sexual intercourse

Question 15

State the functions of the scrotum

Answer 15

*It holds the testicles (also called testes), as well as many nerves and blood vessels.

Question 16

State the functions of the epididymis

Answer 16

*It carries and stores sperm cells that are created in the testes
*to bring the sperm to maturity — the sperm that emerge from the testes are immature and incapable offertilization

Question 17

State the function of the seminal vesicle

Answer 17

*The seminal vesicles make a sugar-rich fluid (fructose) that provides sperm with a source of energy and helps with the sperms’ ability to move (motility).
*The fluid of the seminal vesicles makes up most of the volume of your ejaculatory fluid, or ejaculate which helps wash the sperm into the urethra and dilutes the thick mass of sperm enabling them to be mobile
* Secretes prostaglandins which stimulate contraction of the smooth muscles in both male and female reproductive tracts which in help transportation from their storage site in male to the site of fertilization in female oviduct
*Secretes fibrinogen

Question 18

Name the 3 portions of the urethra

Answer 18

*Prostatic urethra: the uppermost segment within the prostate
*Membrous urethra: the segment within the urethral sphincter
*Penile/ spongy urethra/ carvenous urethra :the lowermost and longest section within the penis

Question 19

What is the function of the ejaculatory ducts?

Answer 19

*Drain and open into the penile urethra

Question 20

How is the urethra able to carry out its two way function?

Answer 20

*When the penis is erect during sex, the flow of urine is blocked from the urethra, allowing only semen to be ejaculated at orgasm.

Question 21

State the function of the prostate gland

Answer 21

*contributes additional fluid to the ejaculate
*Prostate fluids also help to nourish the sperm.
*It secretesproteolytic enzymesinto the semen, which act to break down clotting factors in the ejaculate. This allows the semen to remain in a fluid state, moving throughout the female reproductive tract for potential fertilisation.
*Secretes alkaline fluid that neutralizes the acidic vaginal secretions,sperms are viable in neutral environments
*Releases prostatic clotting enzymes Which acts on the fibrinogen from seminal vesicles to produce fibrin, which clots the semen thus keeping the ejaculated sperms in the female reproductive tract during withdrawal of the penis
* It produces prostate specific antigen,a fibrin degrading enzyme,thus releasing mobile sperm within the female tract

Question 22

State the function of the bulbo-urethral gland

Answer 22

*produce a clear, slippery fluid that empties directly into the urethra during sexual arousal.
*This fluid serves to lubricate the urethra and to neutralize any acidity that may be present due to residual drops of urine in the urethra.

Question 23

State the function of the erectile tissue

Answer 23

The erectile tissues fill with blood during sexual arousal, producing anerection.
The root and body of the penis are spanned by three masses of erectile tissue.

Question 24

Name the 2 paired muscles located in the root of the penis and their functions

Answer 24

*Bulbospongiosus(x2) – associated with the bulb of the penis. It contracts to empty the spongy urethra of any residual semen and urine
*The anterior fibres also aid in maintaining erection by increasing the pressure in the bulb of the penis.

*Ischiocavernosus(x2) – surrounds the left and right crura of the penis.
* It contracts to force blood from the cavernous spaces in the crura into the corpora cavernosa – this helps maintain erection.

Question 25

State the ligaments found at the root of the penis

Answer 25

Suspensory ligament– a condensation of deep fascia. It connects the erectile bodies of the penis to the pubic symphysis.

*Fundiform ligament– a condensation of abdominal subcutaneous tissue. It runs down from the linea alba, surrounding the penis like a sling, and attaching to the pubic symphysis.

Question 26

Which ligament at the root of the penis is a condensation of abdominal subcutaneous tissue.

Answer 26

Fundiform ligament

Question 27

Which ligament connects the erectile bodies of the penis to the pubic symphysis?

Answer 27

suspensory ligament

Question 28

What connects the foreskin to the glans?

Answer 28

*Frenulum

Question 29

What is the potential space between the glans and prepuce is termed ?t

Answer 29

Thepreputial sac.

Question 30

Describe arterial supply to the penis

Answer 30

Main: internal iliac artery branches into internal pudendal artery which gives the:

*the deep arteries of the penis
*dorsal artery of the penis
*bulbo-urethral artery

Question 31

Describe venous drainage to the penis

Answer 31

*The cavernous spaces are drained by thedeep dorsal vein of the penis
– this empties into the prostatic venous plexus.

*Thesuperficial dorsal veins
drain the superficial structures of the penis, such as the skin and cutaneous tissues.

Question 32

Describe the blood supply to the scrotum

Answer 32

*External pudendal artery gives the anterior scrotal artery
*Internal pudendal artery branches into the posterior scrotal artery

Question 33

Describe venous drainage to the scrotum

Answer 33

Scrotal veins drain into the external pudental veins

Question 34

State the fascia layers of the erectal tissue of the penis

Answer 34

*external fascia ofColles(which is in continuity with the fascia of Scarpa which covers the abdominal wall).
*thedeep fascia of the penis(also known asBuck’s fascia)
*tunica albuginea
,forming an individual capsule around each cavernous body and fused in the midline

Question 35

What arteries supplies blood to the testes?

venous supply??

Answer 35

*testicular arteries ,which arise directly from the abdominal aorta
*However, the testes are also supplied by branches of thecremasteric artery(from the inferior epigastric artery) and the artery of the vas deferens (from the inferior vesical artery). These branches give anastomoses to the main testicular artery.

*Thepampiniform plexusin the scrotum – a network of veins wrapped around the testicular artery

*In the retroperitoneal space of the abdomen, the left testicular vein drains into the leftrenal vein, while the right testicular vein drains directly into theinferior vena cava.

Question 36

What is pampiniform plexus?

Answer 36

*a network of veins wrapped around the testicular artery
*Coiling of the testicular v. around the testicular a. in the spermatic cord.

Question 37

What is a frenulum?

Answer 37

a median fold of skin on the ventral surface of the penis.
an elastic band that connects the foreskin and penis glans

Question 38

What is the potential space between the glans and prepuce?

Answer 38

Preputial sac

Question 39

List structures found in the spermatic cord

Answer 39

*the ductus deferens, testiculararteryandveins,lymphvessels, testicularnerve,cremaster musclethat elevates the testes for warmth and at times of sexual stimulation, and aconnective tissue
covering.
*

Question 40

What is the function of the pampiniform plexus?

Answer 40

*Function is to decrease the temperature of the blood coming to the testis through the artery.

*The association of the veins of the pampiniform plexus with the testicular artery constitutes a countercurrent exchange system to cool the blood somewhat on its way to the testis

Question 41

Where is the cremaster m. derived from?

Answer 41

Internal abdominal oblique muscle

Question 41

Describe the pathway of sperm from the testis.

Answer 41

Testis => Head of epididymis => Body of epididymis => Tail of epididymis => Ductus deferens => Ejaculatory Orifice (accessory sex glands also dump secretions into the pelvic urethra creating semen) => Pelvic urethra => Penile urethra = External urethral orifice

Question 42

Name the part of the testes that produce sperms

Answer 42

seminiferous tubules

Question 43

Name the 3 accessory glands of the male reproductive system

Answer 43

Seminal vesicles, prostate gland, bulbourethral gland

Question 44

Where is prostate specific antigen produced!
What disease is it used to screen for?

Answer 44

Prostate gland
Prostate cancer, benign prostatic hypertrophy

Question 45

What are prostaglandins derived from?

Answer 45

Arachidonic acid