Male Reproductive Tract

Question 1

What is the average weight of testis

Answer 1

15-19g

Question 2

What is the capsule of the testis

Answer 2

Tunica vaginalis - projection of the peritoneum. parietal and visceral

Tunica albuginea

Tunica vasculosa

Question 3

Describe the tunica vaginalis

Answer 3

Flattened layer of mesothelial cells

Question 4

Describe the tunica albuginea

Answer 4

Collagen fibres with some fibroblasts, monocytes, nerve fibres

Question 5

Describe the tunica vasculosa

Answer 5

Loose connective tissue containing blood vessels and lymphatics

Question 6

Describe the histology of the testis

Answer 6

Testicular parenchyma is divided inro lobules by septa originating from the capsule

apprx.250 lobules

Each lobule contains 1-4 seminiferous tubules

Question 7

What are the subdivisions of spermatogonia

Answer 7

Type A - dark and pale cells

Type B

Question 8

Describe Sertoli cells

Answer 8

Columnar cells on the basement membrane of the tubule

Send cytoplasmic projections around the germ cells

Nuclei are irregularly shaped, folded and have prominent nucleolus (helps to distinguish from germ cells)

Supportive, phagocytotic and secretory functions

Question 9

Describe the structure of spermatozoa

Answer 9

Head
- acrosomal cap
- nucleus

Midpiece
- spiral mitochondria

Tail
- neck - centrioles
- axoneme
- plasma membrane

Question 10

Describe leydig cells

Answer 10

Present singly and in clusters in the intersitium between tubules

Abundant cytoplasm containing lipid

Reinke’s crystalloids - not seen before puberty

Produce testosterone

Question 11

What cells secrete testosterone

Answer 11

Leydig cells

Question 12

Describe the rete testis

Answer 12

Anastomosing network of tubules at the hilum of the testis

Receive luminal contents from seminiferous tubules

Lined by simple squamous or low columnar epithelium on a relatively thick basement membrane

Have cilia at the luminal surface

Question 13

What is the role of the rete testis

Answer 13

Mixing chamber for contents of seminiferous tubules

Possible secretions

Reabsorption of protein from the luminal contents

Question 14

Describe the rete testis efferent ducts

Answer 14

12-15 convoluted tubules which empty into epididymis

Lined by ciliated and non ciliated columnar epithelium with interspersed cuboidal cells (basal cells) giving pseudostratified appearance

Question 15

Describe the epididymis

Answer 15

A tubular structure 4-5cm long containing a highly convoluted epididymal duct

Lined by tall columnar cells with long atypical cilia (sterocilia - non mobile)

Epithelium supported by a thick basement membrane surrounding which is a well defined muscular coat

Question 16

Describe the vas deferens

Answer 16

30-40cm tubular structure arising from the caudal portion of epididymis

Distal part enlarged to form the ampulla which joins the excretory duct of the seminal vesicle to form the ejaculatory duct

Lined by pseudostratified columnar epithelium comprising of columnar and basal cells

Has thick muscular wall of 3 layers

Question 17

What is the lobes of the prostate

Answer 17

Anterior, middle, posterior and lateral lobes

Peripheral (site of cancer)
Central (enlargement)

Question 18

Describe the prostate

Answer 18

Covered by an ill-defined fibro-connective tissue capsule

Glandular and non glandular components

Ducts
- large primary and small secondary

Acini
- 30 to 50 tubuloalveolar glands with convoluted edges

Question 19

Describe the acini of the prostate

Answer 19

Lined by secretory cells, basal cells and neuroendocrine cells

Secretory cells - located in luminal side. Secrete PSA and PAP into the seminal fluid

Basal cells - form continuous layer

Cells rest on a basement membrane

Question 20

Describe the seminal vesicles

Answer 20

Paired highly coiled tubular structures posterolateral to the bladder

The duct empties into the ejaculatory duct

Lined by tall non-ciliated columnar epithelium

Vacuoles and lipofuscin

Mucosa is folded
Smooth muscle (2 layers)
Adventitia

Question 21

Describe the penis

Answer 21

Corpora caveronsa and corpus spongiosum has same histological features

Irregular vascular spaces separated by fibroelastic tissue and smooth muscles