(1.S) Male Histology & Spermatogenesis

Question 1

What cells are found in the Testis? What are their roles?

Answer 1

• Developing sperms: Spermatogonia -> Spermatocytes -> Spermatids
• Sertoli cells: support developing germ cells & respond to FSH and Testosterone & secrete Mullerian Inhibitory Hormone
• Leydig cells: secrete Testosterone

Question 2

What is the tough fibrous structure surrounds the testes called?

Answer 2

Tunica albuginea

Question 3

What cells produce Testosterone?

Answer 3

Leydig cells (peri-tubular)

Question 4

What cells support the maturing sperm cells?

Answer 4

Sertoli cells (tubular epithelial cells)

Question 5

What cells secrete Mullerian Inhibitory Hormone?

Answer 5

Sertoli cells

Question 6

What are the names changed of developing sperms?

Answer 6

Spermatogonia -> Spermatocytes -> Spermatids

Question 7

Describe the ductual system.

Answer 7

Semiferous Tubule -> Rete Tetis -> Efferent Ductules -> Epididymis -> Vas deferens -> Ejaculatory Duct

Question 8

Describe the course of Vas deferens.

Answer 8

Through Inguinal Canal -> over Internal Iliac vessels -> above and medial to Ureter -> behind Seminal Vesicles -> join and form Ejaculatory Duct

Question 9

What are the epithelial linings of Epididymis and Vas deferens? How does it help with transporting sperm cells?

Answer 9

Pseudostratified Columnar, lined by Stereocilia (more in Epididymis)

Question 10

What forms the septae inside the Prostate Gland? What structures are formed?

Answer 10

• Fibromuscular capsule
• Transitional Zone anteriorly
• Central Zone posteriorly
• Peripheral Zone

Question 11

In which zone does Benign Prostatic Hyperplasia most likely to occur? What symptoms does it cause?

Answer 11

• Transitional and Central zones
• Dysuria, nocturia, urgency
• Due to lie closely to urethra

Question 12

In which zone does Prostatic Carcinoma most likely to occur? Why is it often delayed in diagnosis? How is it diagnosed?

Answer 12

• Peripheral zone
• Late symptoms
• Elevated Prostate Specific Antigen
• Digital Rectal Examination

Question 13

What is the Spermatogenic Cycle?

Answer 13

The amount of time for the development of one A1 Spermatogonia into 256 Spermatids.

Question 14

What is the Spermatogenic Wave?

Answer 14

The distance of the segments in the Semiferous Tubule where the sperms are found at the same developmental stage.

Question 15

What do the germ cells that colonise the sex cords in the Primordial gonad of men proliferate to become?

Answer 15

Spermatogonia stem cells

Question 16

What do A1 Spermatogonia go on to produce?

Answer 16

Further differentiate into:

• more Type A Spermatogonia
• Type B Spermatogonia

Question 17

What cells do Type B Spermatogonia derive to?

Answer 17

64 mitosis -> 64 Primary Spermatocytes

Question 18

What is produced from one Primary Spermatocyte after meiosis?

Answer 18

• Meiosis I -> 2 Diploid Secondary Spermatocytes

- Meiosis II -> 4 Haploid Spermatids

Question 19

How are the primary Spermatocytes connected to each other in a chain?

Answer 19

Cytoplasmic bridges

Question 20

Briefly describe the process of Spermatogenesis.

Answer 20

• Germ cells colonise the Sex Cords (after puberty become Semiferous Tubules)
• Before birth Germ cells emerge into Type A Spermatogonia stem cells
• Type A Spermatogonia differentiate into more Type A and Type B Spermatogonia
• Each Type B Spermatogonium undergoes 64 mitosis into 64 Primary Spermatocytes that are connected by Cytoplasmic bridges
• Each Primary Spermatocyte undergoes meiosis into 4 Spermatids that form a Spermatozoa Chain

Question 21

Name 3 parts of the male reproductive tract that are lined with Pseudostratified columnar epithelium.

Answer 21

• Epididymis
• Vas deferens
• Seminal Vesicles

Question 22

How many days does it take for Spermatozoa to mature? Which two places foes it occur?

Answer 22

• 74 days
• Semiferous Tubules
• Epidydimis