MALE REPRODUCTIVE SYSTEM

prolate spheroid

shape of the testes

18.6 +- 4.8

mean volume of the testes in mL

4.6

length of the testes in cm

2.6

width of the testes in cm

scrotum

• location of the testes

• for thermoregulation

tunica vaginallis

• membrane of the testes

• closed peritoneal sac surrounding the front and sides of the testis

• extends upward over the spermatic cord

tunica vasculosa

• membrane of the testes

• closed peritoneal sac surrounding the front and sides of the testis

• innermost of the three layers that form the capsule of the testis

tunica albuginea

• membrane of the testes

• extends into the testicle

septations

formed by the tunica albuginea

pyramidal lobules

the tunica albuginea gives rise to ~250-300 _

400

the testes is composed of _ m of seminiferous tubules

50

the semineferous tubules compose _% of testicular mass

Leydig cells

there are 200 million androgen producing _

internal spermatic artery

the blood supply from the testicular arteries originate from the _

pampiniform plexus

• blood supply

• gives rise to internal spermatic veins

retes

the pampiniform plexus is similar to _ in mammals for temperature regulation

165

diameter of the seminiferous tubules in um

basement membrane

• function of the sertoli cells

• line the _

tight junctions

• function of the sertoli cells

• forms _

blood-testis

• function of the sertoli cells

• creates the _ barrier

base to lumen

• function of the sertoli cells

• responsible for moving germ cells from _

phagocytose

• function of the sertoli cells

• _ damaged cells and residual bodies

sertoli cells

cells which secrete androgen-binding protein

FSH

sertoli cells respond to _ to secrete androgen-binding protein

testosterone

sertoli cells respond to _ to secrete androgen-binding protein

ABP

provides high concentration of testosterone to sperm in the lumen

spermatogonium

• germ cell 1

• undergoes mitotic division

primary spermatocyte

• germ cell 2

• undergoes meiosis I

secondary spermatocyte

• germ cell 3

• undergoes meiosis II

spermatid

• germ cell 4

• undergoes differentiation where the Sertoli cells provide nutrients

sperm

product of spermatogenesis

seminiferous tubules

passage of sperm 1

tubuli recti

passage of sperm 2

rete testis

passage of sperm 3

efferent ductules

passage of sperm 4

epididymis

passage of sperm 5

vas deferens

passage of sperm 6

ejaculatory duct

passage of sperm 7

urethra

passage of sperm 8

fluid pressure

sperm movement is through testicular _

ciliary

sperm movement is through _ motion

duct contraction

sperm movement is through _

epididymis

• accessory structure

• area of storage and further maturation of sperm cells

reservoir

• accessory structure

• the epididymis serves as a _

12-14

• accessory structure

• epididymis transit takes _ days

vas deferens

• accessory structure

• muscular duct

• 35-50 cm long

peristalsis

movement produced in the vas deferens

seminal vesicles

• accessory structures

• produce fructose and seminal fluid

prostate

• accessory structures

• alkaline secretions of seminal fluid

bulbourethral glands

• accessory structures

• Cowper’s gland

• alkaline fluid and lubrication

glands of littre

• accessory structures

• mucus for lubrication

fructose

_ can enter cells much more easier compared to glucose

testosterone

• physiology

• primary male hormone responsible for regulating sex differentiation, producing male sex characteristics, spermatogenesis, and fertility

DHT

• physiology

• involved primarily in the sexual differentiation of organs

estradiol

• physiology

• essential for modulating libido, erectile function, and spermatogenesis

95

leydig cells produce _% of testosterone

DHT

secreted by testes

DHEA

secreted by testes

androstendione

secreted by testes

estradiol

secreted by Leydig cells

estrone

secreted by Leydig cells

pregnenolone

secreted by Leydig cells

progesterone

secreted by Leydig cells

17 alpha hydroxypregnenolone

secreted by Leydig cells

17 alpha hydroxyprogesterone

secreted by Leydig cells

peripheral

• hormone biosynthesis

• DHT and estradiol are converted in the _ tissues

80

• hormone biosynthesis

• DHT and estradiol compose _% of circulating concentration

genitalia

• androgen action

• differentiation of internal and external _

puberty

• androgen action

• mediates growth of scrotum, epididymis, vas deferens, seminal vesicles, prostate, and penis during _

skeletal muscle

• androgen action

• stimulates _ growth

laryngeal

• androgen action

• stimulates _ growth

epiphyseal cartilaginous

• androgen action

• stimulates _ plate growth

secondary

• androgen action

• stimulates _ hair growth

sebaceous gland

• androgen action

• stimulates _ activity

GnRH

• Hypothalamic-Pituitary-Leydig Cell Axis

• hypothalamus secretes _ every 30-120 minutes

LH and FSH

GnRH causes the release of both _

DHT

• negative feedback of androgens

• _ reduces LH pulse frequency

estradiol

• negative feedback of androgens

• _ reduces amplitude

FSH

• Hypothalamic-Pituitary-Leydig Cell Axis

• _ binds to receptors on Sertoli cells

ABP

• Hypothalamic-Pituitary-Leydig Cell Axis

• FSH binding on Sertoli cells produce _

FSH

• Hypothalamic-Pituitary-Leydig Cell Axis

• necessary for initiation of spermatogenesis

FSH and testosterone

• Hypothalamic-Pituitary-Leydig Cell Axis

• for full maturation, both _ are needed

IGF-1

secreted by Sertoli cells

Müllerian duct inhibitory factor

secreted by Sertoli cells

FSH

• secreted by Sertoli cells

• inhibin B inhibits _ secretion

LH

• secreted by Sertoli cells

• inhibin B spares _

ambiguous genitalia

• testosterone deficiency

• 2nd-3rd month AOG

cryptorchidism

• testosterone deficiency

• 3rd trimester

micropenis

• testosterone deficiency

• 3rd trimester

secondary

• prepubertal testosterone deficiency

• poor _ sexual development

eunuchoid

• prepubertal testosterone deficiency

• poor _ proportions

enlarge

• prepubertal testosterone deficiency

• penis and testes fail to _

rugae

• prepubertal testosterone deficiency

• scrotum does not develop _

• folds which allow for expansion

high pitched

• prepubertal testosterone deficiency

• _ voice

muscle mass

• prepubertal testosterone deficiency

• poor _

axilla and pubic

• prepubertal testosterone deficiency

• poor secondary sexual hair growth → _ hair

growth spurt

• prepubertal testosterone deficiency

• no prepubertal _

open

• prepubertal testosterone deficiency

• epiphyseal plates remain _ longer

libido

• postpubertal testosterone deficiency

• decreased _

erectile dysfunction

• postpubertal testosterone deficiency

• _