Male Reproductive System

Front 1

Intratesticular ducts

Back 1

1. Tubuli Recti
2. Rete Testis
3. Ductus efferentes

Front 2

Extratesticular ducts

Back 2

1. Ductus epididymis
2. Ductus deferens
3. Ejaculatory ducts
4. Urethra

Front 3

Accessory male organs

Back 3

1. Seminal vesicles
2. Prostate
3. Bulbourethral gland

Front 4

Cryptorchidism

Back 4

Hidden testes; failure of testicular descent into scrotal sac

Must be corrected; has implications on spermatogenesis and development of testicular malignancies

Front 5

Layers of Scrotum and Testes (outermost to innermost)

Back 5

Skin
Dartos
Colles' fascia (continuous with dartos anteriorly)
Parietal tunica vaginalis
Potential space (site of accumulation of blood, fluid, lymph, intestine)
Visceral tunica vaginalis
Tunica albuginea

Some Damn Englishman Called Them Testis

Front 6

What maintains the lower temperature of the scrotal sac?

Back 6

1. Pampiniform plexus of veins (countercurrent heat exchange)
2. Sweat glands of scrotal skin

Front 7

Cellular components of scrotal sac

Back 7

Seminiferous epithelium
1. Spermatogenic cells
2. Sertoli cells
Seminiferous interstitium
1. Leydig cells

Front 8

Spermatogenic cells

Back 8

1. Ad: dark nuclei, divide into Ap and Ad (maintain supply of precursor cell)
2. Ap: pale nuclei; divide by mitosis to produce B type cells
3. B: divide to give rise to primary spermatocytes
4. Primary spermatocytes
5. Secondary spermatocytes
6. Spermatids

Front 9

Sertoli cells

Back 9

Supporting (sustentacular) cells

Stimulated by FSH

Produce inhibin, androgen binding protein (ABP)

Front 10

Leydig cells

Back 10

Stimulated by LH

Produce testosterone

Front 11

Regulation of Leydig cell

Back 11

Anterior pituitary -> LH -> Leydig production of testosterone

Testosterone production from Leydig provides negative feedback to hypothalamus to inhibit GnRH release

Front 12

Regulation of Sertoli cells

Back 12

Anterior pituitary -> FSH -> Sertoli production of ABP, inhibin

Inhibin provides negative feedback to hypothalamus to inhibit GnRH release

Front 13

Testosterone function in utero

Back 13

Development of penis and male accessory sex organs

Front 14

Testosterone function at puberty

Back 14

Induces development of secondary sexual characteristics
Maintains structure and function of ducts and accessory glands
Stimulates spermatogenesis

Front 15

Testosterone function after puberty

Back 15

Same as function throughout puberty
Feedback mechanism to control pituitary output of LH

Front 16

Spermatogenesis phases

Back 16

1. Spermatogonial phase
2. Spermatocyte phase
3. Spermatid phase

Front 17

Spermatogonial phase

Back 17

Division by mitosis
Ad divide into Ad and Ap
Ap give rise to B type cells
B type cells give rise to spermatogonia

Front 18

Spermatocyte phase

Back 18

Division by meiosis
Primary spermatocytes undergo Meiosis I to give rise to secondary spermatocytes
Secondary spermatocytes undergo Meiosis II to give rise to spermatids

Front 19

Spermatid phase

Back 19

No further division
Maturation into spermatozoa

Front 20

Phases of spermatozoa maturation

Back 20

1. Golgi phase
2. Cap phase
3. Acrosome phase
4. Maturation phase

Front 21

Golgi Phase

Back 21

Proacrosomal vesicles formed by Golgi
Anterior pole is marked

Front 22

Cap Phase

Back 22

Cap forms over nucleus from acrosomal vesicle

Front 23

Acrosome Phase

Back 23

Head of spermatozoa rotates 180 degrees
Head now oriented towards base of seminiferous epithelium
Elongation and condensation of nucleus
Neck and tail structures elaborated

Front 24

Maturation Phase

Back 24

Residual cytoplasm phagocytized by Sertoli cell
Spermatozoa release via spermiation

Front 25

Sertoli cell function

Back 25

1. Nurture developing germ cells
2. Release mature spermatozoa into lumina of seminiferous tubule
3. Phagocytize residual cytoplasm and degenerating germ cells
4. Production of hormones: 1) inhibin, 2) ABP, 3) Antimullerian hormone)
5. Form blood-testis barrier
6. Secrete medium rich in fructose to nourish and facilitate spermatozoa transport
7. Make testicular transferrin

Front 26

Epithelium of testicular ducts:

Back 26

1. Tubuli Rect - Sertoli cells
2. Rete Testis - simple cuboidal, low columnar
3. Ductus efferentes - pseudostratified columnar
4. Ductus epididymis - pseudostratified columnar
5. Ductus deferens - pseudostratified columnar

Front 27

Ductus epididymis epithelial cell types

Back 27

1. Basal cells: stem cells
2. Principal cells: tall cells with stereocilia

Front 28

Principal cells of ductus epididymis (function)

Back 28

1. Absorb testicular fluid
2. Phagocytize and digest degenerating spermatozoa
3. Secrete agents involved in functional maturation of spermatozoa

Front 29

Ampulla

Back 29

Enlargement at distal end of vas deferens that joins with seminal vesicle

Front 30

What forms the ejaculatory duct?

Back 30

Joining of vas deferens (ampulla) and seminal vesicle

Front 31

Colliculus seminalis

Back 31

Site where ejaculatory duct pierces posterior of prostatic urethra;

Cresent shaped opening in substance of prostate gland.

Front 32

Prostatic utricle

Back 32

Within the colliculus seminalis; opens into prostatic urethra.

Front 33

What do the different parts of the male urethra pass through?

Back 33

1. Prostatic urethra - through the prostate gland
2. Membranous urethra - through urogenital diaphragm
3. Penile urethra - through corpus spongiosum

Front 34

Seminal Vesicle (function)

Back 34

Epithelium secretion of:
1. Fructose
2. Prostoglandin
3. Citrate
Produces 70-80% of ejaculate

Front 35

Prostate Gland (function)

Back 35

Secretes:
1. Citric acid
2. Acid phosphatase
3. Fibrinolysin (liquifies semen)
4. Prostate Specific Antigen

Front 36

Corpora Amylacea

Back 36

Prostatic concretions contained within alveoli

Front 37

What type of gland is the prostate gland?

Back 37

Compound tubuloacinar

Front 38

Bulbourethral gland (function)

Back 38

Produces preseminal fluid
Mucus like secretion helps lubricate lumen of urethra

Front 39

What cell types are in the seminal vesicle epithelium?

Back 39

Epithelium: Pseudostratified columnar
Short basal cells (stem cells)
Tall non-ciliated columnar cells (secretory)

Front 40

Which of the accessory male organs are testosterone dependent?

Back 40

All of them! (Seminal vesicles, prostate gland, bulbourethral glands)

Height and extent of epithelial cells are testosterone dependent

Front 41

Corpora cavernosa

Back 41

Two dorsal cylinders of the penis that terminate at glans penis

Front 42

Corpora spongiosum

Back 42

One ventral cylinder that persists through and forms glans penis

Front 43

Which of the cylinders contain erectile tissue?

Back 43

All 3 (both corpora cavernosum and the one corpora spongiosum)

Front 44

Blood supply to the penis

Back 44

Dorsal and deep arteries
Helicine arteries supply erectile tissue

Front 45

Sperm head

Back 45

Overlying plasma membrane
Acrosome
1. Outer acrosome membrane
2. Hydrolytic enzymes
3. Inner acrosome membrane
Nucleus (inner and outer membranes with condensed chromatin)
Postacrosomal region

Front 46

Sperm tail components

Back 46

1. Midpiece
2. Principal piece
3. End piece

Front 47

Midpiece

Back 47

1. axoneme: 9+2 MTs at core; dynein arms have ATPase
2. outer coarse (dense) fibers: surround axoneme, longitudinal arrangement
3. mitochondrial sheath***
4. plasma membrane of tail

Front 48

Principal piece

Back 48

1. axoneme
2. outer coarse (dense) fibers
3. Outer circumferential fibers (fibrous sheath)***
4. plasma membrane of tail

Front 49

End piece

Back 49

(similar structure to cilium)
1. axoneme
2. plasma membrane of tail

Front 50

What structures are essential to sperm motility?

Back 50

Sperm mitochondria, dynein arms, axoneme, outer coarse (dense) fibers, outer circumferential fibers (fibrous sheath)

Front 51

Where is the motility of sperm conferred?

Back 51

Ductus epididymis

Front 52

Fertilization (basic process)

Back 52

1. binding of sperm to zona pellucida
2. acrosome reaction
- fusion of sperm head and
acrosomal membranes
- exposure to hydrolytic enzymes
- lysis of path thru zona pellucida
3. fusion of PM of sperm and oocyte
4. entry of sperm nucleus into oocyte cytoplasm

Front 53

What is contained within the vas deferens?

Back 53

Spermatic cord

Front 54

Describe distinct characteristics of the vas deferens?

Back 54

Muscularis externa is very thick, composed of inner longitudinal, middle circular, thin outer longitudinal

Adventitia contains many blood vessels and nerves; merges with surrounding CT of spermatic cord

Front 55

What is the prostate gland embedded in?

Back 55

Fibromuscular stroma - strands of smooth muscle fibers along fibrous tissue (elastic fibers and collagen)