Male Reproductive

Question 1

What encodes TDF?

Answer 1

Testis-determining factor is encoded by the SRY gene, has a molecular domain that binds into a specific region of DNA and alters its structure.

Question 2

What gene is required for the development of the urogenital system?

Answer 2

WT-1 gene is required for the formation of the urogenital system and the regulation of the SRY transcription.

Question 3

Children with familial Wilm’s tumor and children with accompanied genitourinary malformations have a mutation on what gene?

Answer 3

WT-1 gene mutation

Question 4

What does the SOX-9 gene do?

Answer 4

It is found in the genital ridges, activates the AMH gene that is responsible for mullerian-inhibiting factor synthesis.

Question 5

what does the SF-1 gene do?

Answer 5

Regulates the expression of a number of steroidogenic genes.

Question 6

What is DAX-1 gene responsible for?

A mutation in this gene will cause what kind of hypoplasia?

Answer 6

Encodes for nuclear receptor DAX-1. Activation of this receptor suppresses the SRY gene during gonadal sex differentiation and its mutation is responsible for congenital adrenal hypoplasia.

Question 7

Where do the testes developed?

Answer 7

In the posterior wall of the abdomen, and later descend into the scrotum.

Question 8

Testes like ovaries, are derived from three souces…..

Answer 8

Intermedial mesoderm
Mesodermal epithelium
Primordial germ cells

Question 9

What derives from intermediate mesoderm?

Answer 9

It forms the urogenital ridges on the posterior abdominal walls, giving rise to Leydig cells (interstitial cells) and myoid cells (peritubular contractile cells).

Question 10

What derives from Mesodermal epithelium?

Answer 10

Coelomic mesothelium, lines the urogenital ridges and gives rise to sertoli cells.

Question 11

What derives from primordial germ cells?

Answer 11

They migrate from yolk sac into developing gonads, where they divide and differentiate into spermatogonia.

Question 12

what causes development and differentiation of external genitalia?

Answer 12

Dihydrotestosterone (DHT)

Question 13

What enzyme coverts testosterone to DHT?

Answer 13

5-alpha-reductase

Question 14

What causes cryptorchidism?

What corrects it?

Answer 14

Obstructed descend of testis (undescended testes). This condition is common 30% in premature newborns and about 1% in full term.

A Orchiopexy should be performed, preferably before histologic changes become irreversible at approx. 2 years of age.

Question 15

Embryology: Testosterone acts on ? to give rise to ?

Answer 15

a. Acts on mesonephric ducts and tubules to form:
i. Efferent tubules
ii. Epididymis
iii. Ductus deferens
iv. Seminal vesicles
v. Ejaculatory duct

Question 16

Embryology: DHT acts on ? to give rise to ?

Answer 16

a. Acts on urogenital sinus indifferent genitalia to form:
i. Penis
ii. Scrotum
iii. Prostate gland
iv. Prostatic urethra
v. Penile urethra.

Question 17

How do testes get their blood supply?

Answer 17

Each testis receives blood through a testicular artery, a direct branch of the abdominal aorta

Question 18

What muscle responds to changes in ambient temperature for the testes?

Answer 18

Cremaster muscle. When it contracts moves testes closer to the abdomen, when it relaxes , it lowers them within the scrotum.

Question 19

What does contraction of dartos muscle do?

Answer 19

It helps the scrotum to wrinkle when cold to help regulate heat loss.

Question 20

What does the tunica vaginalis do?

Answer 20

Tunica vaginalis: covers the anterolateral surface of the testes.

Question 21

What does the tunica albuginea do?

Answer 21

Covers each testis. The inner part of this capsule, the tunica vasculosa (loose connective tissue that contains blood vessels).

Question 22

What can lead to sexual precocity in pubertal boys, and gynecomastia and feminization in adult males?

Answer 22

Leydig cells tumors. This represent predominantely benign tumor, which occur during two distinct periods (in childhood or adults between 20-60).

They are hormone active and secrete androgens or combination of androgens and estrogens.

Question 23

What does the acrosomal cap contains?

Answer 23

Hyaluronidase, neuraminidase, acid phosphate, and a trypsin-like protease called acrosin.

These are essential for penetration to the zona pellucida of the ovum.

Question 24

Where do sperm cells acquire their motility?

Answer 24

Newly released sperm cells are processed in the epididymis where they acquire motility and undergo further maturation.

Question 25

What regulates sperm cell motility?

Answer 25

Initiation of sperm cell motility during cell transit through the epididymis is most likely related to changes in the intracellular levels of i- cAMP
ii- Ca 2+
iii- Intracellular pH.

Question 26

Histologically , what kind of cells are sertoli cells?

Answer 26

Tall columnar, non-replicating epithelial cells that rest on the thick multilayered basal lamina of the seminiferous epithelium.

Question 27

Where do we find inclusion bodies (of Charcot-Bottcher)?

Answer 27

They are found in the basal cytoplasm of sertoli cells.

Question 28

What receptors do sertoli cells have?

Answer 28

FSH and testosterone receptors are on Sertoli cells which controls its secretions.

Question 29

What are the secretions of sertoli cells?

Answer 29

1. Fluid that facilitates passage of the maturing sperm along the siminiferous tubules to the intratesticular ducts.
2. Androgen binding protein (ABP).
3. Inhibin: glycoprotein hormone that inhibits FSH release from anterior pituitary
4. Plasminogen activator: converts
   plaminogen to plasmin, transferrin, and ceruloplasmin (copper transporter).
5. They also secrete growth factors or paracrine factors MIF, stem cell factor SCF and glial cell line-derived neurotrophic factor GDNF.

Question 30

What are the intratesticular ducts lined with?

Answer 30

They are lined only with sertoli cells. Straight tubules or tubuli recti. Near their termination, the lining changes to a simple cuboidal epithelium.

Question 31

What is the immunologic importance of blood-testis barrier?

Answer 31

1. Spermatozoa and spermatogenic cells possess molecules that are unique to these cells and are recognized as “foreign” by the immune system.
2. Spermatozoa are first produced at puberty, long after the individual has become immunocompetent.

Failure of the spermatogenic cells and spematoza to remain isolate results in the production of sperm-specific antibodies. This can result after a vasectomy also, as spermatozoa maybe exposed to body. This causes infertily, the antibodies cause the sperm to agglutinate, preventing movement and interaction with the ovum.

Question 32

What are the efferent ductules lined with?

Answer 32

They are lined with pseudostratified columnar epithelium.

Question 33

What kind of cells does the epididymis have?

What are the migrating lymphocytes called?

Answer 33

It has principal and basal cells. Migrating lymphocytes called Halo cells are often found within the epithelium.

Question 34

What does the spermatic cord contains?

Answer 34

• Ductus deferens
• Testicular artery.
• Small arteries to the ductus deferens and cremaster muscle.
• The pampiniform plexus.
• lymphatic vessels.
• sympathetic nerve fibers.

And the genital branch of the genitofemoral nerve.

Question 35

What lines the ductus deferens?

Answer 35

Pseudostratified columnar epithelium.

Question 36

Seminal vesicles are posterior to what structure?

Answer 36

Urinary bladder.

Question 37

Where is the prostate gland located and what does it secrete?

Answer 37

The larges accessory gland. It main function is to secrete clear, slightly alkaline pH 7.29 fluid that contributes tot eh formation of the seminal fluid. The gland is located in the pelvis inferior to the bladder.

Question 38

What does the prostate glands secretes?

Answer 38

• Prostate gland secretes prostatic acid phosphatase (PAP), fibrinolysis, citric acid, and prostate-specific antigen (PSA).

Question 39

A large amount of PSA in blood is indicative of what? 4-10 or greater than 10 ng/mL.

Answer 39

Prostate cancer. It can also be associated with prostatitis, interrupted blood flow to the prostate or BPH.

Prostate-specific antigen (PSA): PSA is secreted into prosttatic gland alveoli and ultimately incorporated into seminal fluid. Because PSA is predominately released into prostatic secretion, only very small amoung of PSA is circulating in the blood of a healthy individual. However, prostate cancer, serum PSA increases.

Question 40

Where are the parasympathetic pre-ganglionic fibers for the female repro system?

Answer 40

S2 to S4, axons from the pelvic sphlanic nerves, which interact with the inferior hypogastric plexus.

Question 41

What are the sympathetic pre-ganglionic axons located? female repro

Answer 41

Sacral splanchnic nerves

Question 42

Post gaglionic neuronal cell bodies are located? female repro.

Answer 42

In the inferior hypogastric plexus?