Histology of the Testis and Excretory Ducts Flashcards Preview

Block I: Reproduction & Sexuality > Histology of the Testis and Excretory Ducts > Flashcards

Flashcards in Histology of the Testis and Excretory Ducts Deck (45):
1

2 functions of the male reproductive system

  • Elaboration of sex hormones
  • Formation and delivery of the male gametes into the female reproductive tract

2

Primary function of the testis

Production of spermatozoa (male gamete)

3

 Androgen-producing cell of the testis

Leydig cell

4

4 functions of androgens

  1. Embryo development of male fetus
  2. Initiation and maintenance of spermatozoa production
  3. Development of accessory organs and secondary sex characteristics
  4. Secretion of accessory glands

5

Capsule of connective tissue surrounding the testis

Tunica albuginea

6

Tubules contained in the lobules of the testis

Seminiferous tubules

7

End of the seminiferous tubules

Rete testis

8

What embeds the seminiferous tubules in the lobules of the testis?

Connective tissue stroma (interstitium)

9

Location of Leydig cells

Interstitium surrounding the seminiferous tubules

10

6 histological characteristics of Leydig cells

  • Polyhedral
  • Round, homogenous nuclei
  • Triangular clusters
  • Acidophilic
  • Elaborate SER
  • Large juxtanuclear Golgi apparatus
  • Abundant mitochondria
  • Peroxisomes

11

2 electron micrograph characteristics of steroid producing cells

  • Lots of mitochondria
  • Lots of SER

12

Hormone that stimulates Leydig cells to secrete androgens

LH

13

2 effects of Mullerian inhibiting substance (MIS)

  • Implication in the regulation of steroidogenesis
  • Mullerian duct regression

14

Contractile elements of the seminiferous tubules

Myoid cells

15

Function of myoid cells of the seminiferous tubules

Peristaltic movement to transport the currently immotile spermatozoa from the seminiferous tubule towards the rete testis

16

5 contents of the interestitium of the lumen of the testis

  • Leydig cells
  • Lymphatics
  • Blood vessels
  • Fibrocytes
  • Macrophages

17

Function of macrophages in proximity to Leydig cells

Production of cytokines that can crosstalk with Leydig cells

18

Somatic cells of the seminiferous epithelium

Sertoli cells

19

7 functions of the Sertoli cell

  1. Supportive or sustentacular (structural support)
  2. Nurse cells (biochemical support)
  3. Formation of the Blood-Testis Barrier (tight junctions)
  4. Secrete lumincal fluids including several proteins, such as enzymes and transport proteins
  5. Secrete hormones and factors
  6. Endocytic (receptor-mediated endocytosis) and phagocytic function
  7. Serve as lifts displacing the early spermatocytes from the basal compartment to the adluminal compartment (so blood-testis barrier is not disrupted)

20

How are Leydig cells able to renew their cytoplasm

Autophagocytosis

21

Enzymes secreted by Sertoli cells

Proteases

22

3 types of transport proteins secreted by Sertoli cells

  • Androgen binding protein
  • Transferrin
  • Apolipoprotein J

23

2 hormones and factors secreted by sertoli cells

  • Inhibin
  • Anti-Muellerian Hormone

24

Function of inhibin

Suppression of FSH

25

Function of Anti-Muellerian Hormone

Promote regression of the Muellerian ducts

26

Define rete testis

Anastomosed channels lined with a simple epithelium of low cuboidal cells. The epithelium of the rete testis is not surrounded by myoid cells

27

Two types of cells in the epithelium of the efferent ducts (ductuli efferentes) and their respective functions

Non-ciliated = absorption (endocytic)

Ciliated = move sperm towards epididymis

28

Role of estrogen in the ductuli efferentes

Stimulate non-ciliated cells of the epithelium to absorb (if receptor gene is knocked out, testis becomes full of fluid)

29

3 regions of the epididymis

  • Head (caput)
  • Body
  • Tail (cauda)

30

Type of epithelium in the epididymis

Pseudostratified

31

Describe the function of the epididymis epithelial cells

Taller columnar cells contain stereocilia that are actually microvilli engaged in absorption

32

Site of maturation of spermatozoa

Epididymis

33

Describe the histology of the vas deferens

  • Surrounded by lamina propria (several layers of myoid cells)
  • Outer smooth muscle cells (non-specifically oriented)
  • Taller epithelial cells have stereocilia (pseudostratified)

34

Type of tissue surrounding the urethra in the penis and what it becomes towards the tip

Corpus spongiosum, which enlarges to form the glans

35

Erectile tissue of the penis

Corpus cavernosum and corpus spongiosum (contains smooth muscle and endothelium as well as deep arteries)

36

Tissue surrounding the corpus cavernosum of the penis

Tunica albuginea (NOTE: Different from that of the testis)

37

Describe the non-erect state of the penis in terms of blood flow

Minimal

38

Describe how erection physiologically occurs in the penis

  1. Vasodilator impulses of parasympathetic origin causes relaxation of penile vessels and cavernous smooth muscle
  2. Amount of blood increases in the vascular spaces of the corpus cavernosa and corpus spongiosum --> rigidity of the penis as it enlarges within the confines of the tough connective tissue of the tunica albuginea.

39

Define erectile dysfunction

Inability to develop or mantain an erection of the penis for a satisfactory sexual performance

40

Define Peyronie's disease

Most consistent abnormality occurs in the orientation and character of the collagen that comprises the tunica albuginea. Plaque is formed and causes erect penis to curve to one side (may be painful and require corrective surgery)

41

3 types of spermatogenic cells

  • Spermatogonia
  • Spermatocyte
  • Spermatid

42

Location within the epithelium of seminiferous tubules of spermatogonia

Resting on the basement membrane

43

Location within the epithelium of seminiferous tubules of spermatocytes

Generally located in the middle of the seminiferous epithelium

44

Location within the epithelium of seminiferous tubules of spermatids (round and elongated)

Adluminal region

45

5 histologic characteristics of Sertoli cells

  • Elaborate endoplasmic reticulum
  • Well-developed Golgi apparatus
  • Generally ovoid or triangular nuclei
  • Euchromatin and distinct nucleolus in nuclei
  • Large number of lysosomes