Male Reproductive System Flashcards
What is the function of the testes?
Produce sperm and the make sex hormone, testoserone
What are the functions of ducts in the male reproductive system?
Ducts transport, store and assist in maturation of sperm
What is the function of accessory sex organs in the male reproductive system?
Secrete most of the liquid portion of semen
The penis contains______ _________ a passageway for _________ of _______ and __________ of _________
The urethra
Ejaculation
Semen
Excretion
Urine
What are the supporting structures of the male reproductive system and what are ther functions?
Penis- delivers sperm to the female reproductive system
Scrotum- supports the testes
What are the 5 ducts thatbmake up the duct system?
Urethra
Epidydmis
Ductus deferens
Ejaculatiry duct
Efferent ductules
What are the accessory glands of the male reproductive system?
Seminal vesicles
Prostate gland
Bulbourethral gland
What are the functions of Leydig cells and where are they located!
SECRETE TESTOSERONE
Are interstitial cells located between adjacent seminiferous tubules
What are the functions of the Sertoli cells?
- Forms the BLOOD-TESTES barrier which isolates the developing gametes from the blood, thus PREVENTING AN IMMUNE RESPONSE against spermatogenic cell’s surface antigens which the immune system recognizes as foreign
- Secrete inhibin to inhibit FSH secretion
- Secrete androgen-binding protein which binds to testoserone to keeps its concentration high
What are the types of spermatogenic cells?
Spermatogonia( 2n)/stem cells
Primary spermatocytes(2n, 4d)
Secondary spermatocytes (1n, 2d)
- Spermatids(1n, 1d)
- Spermatozoa(1n, 1d)
What is the function of mitochondria in the middle piece of spermatozoa?
Mitochondria provide ATP for sperm motility
What is the function of the end piece of the tail of spermatozoa?
End piece contains core of microtubules and dynein motor proteins
What is the function of the acrosome of spermatozoa?
Vesicle contains enzymes required for penetration of the zona pellucida of the oocyte
What is the nucleus of a spermatozoa comprised of?
23 condensed chromosomes(22, X or Y)
Explain hormonal secretion of FSH
- Hypothalamus releases GnRH which stimulates gonadotrophs to release LH and FSH
- LH stimulates testosterone secretion by Leydig cells
- FSH along with testosterone stimulates spermatogenesis
- testosterone binds to androgen receptors on spermatogenic cells while FSH binds to FSH receptors on spermatogenic cells
- Spermatogenic cells release androgen binding protein as well as inhibin.
- Inhibin decreases FSH release
Explain testosterone release
- GnRH from the hypothalamus stimulates gonadotrophs to release LH
- LH stimulates testosterone secretion from Leydig cells
- testosterone acts on spermatogenic cells to stimulate spermatogenesis or act as testosterone/ Duhydrotestosterone and complete a number of other functions?
What are the functions of testoserone?
- Regulates the male pattern of birth
- Regulates the enlargement of male sex organs and expression of male secondary sex characteristics(starting at puberty)
- Anabolism (protein synthesis)
Explain the negative feedback control of testosterone
- Increasing blood levels of testosterone inhibit. GnRH release in the hypothalamus
- this lowers LH in systemic blood, causing Leydig cells in Testes to secrete less testosterone
- decreased testosterone in blood causes a return to homeostasis
Name the excurrent ducts
- Efferent ducts
- Epididymis
- Ductus deferens
- Ejaculatory ducts
Name the intratesticular ducts
Seminiferous tubules
Straight tubules
Rete testis
What are the seminiferous epithelium made up of?
Seminiferous epithelium
Where are the straight tubule(tubuli recti)?
These are the short terminal portion of the seminiferous tubule
What do the straight tubules contain?
Contain Sertoli cells changing to simple cuboidal
What are the efferent ducts made of?
Pseudostratifidd columnar epithelium
Name the parts of the epidydymis
Head, body and tail
What is the epididymis comprised of?
Psuedostratified columnar epithelium with stereocilia
What is the Vas/Ductus deferens made up of?
Psuedostratified columnar epithelium with stereocilia
What are the ejaculatory ducts made up of?
Union of the duct of seminal vehicle and ampulla of ductus deferens
What is the rete testis? What is it made of?
Network of channels and an inter testicular duct
Made of simple cuboidal to low columnar
What is the length of development of a normal sperm?
65-75 days
What are the functions of the seminal vesicles?
- Secrete an alkaline, viscous fluid, fructose
- this allows ATP production by sperm(motility)
- this secretion includes prostaglandins and clotting responses
- Produces about 60% of volume of semen
What are the seminal vesicles?
Paired glands posterior to bladder
- duct joins ampulla of ductus deferens to form ejaculatory duct
What are the functions of the prostate glands?
Secretes a milky, slightly acidic fluid into the prostatic urethra
- Citric acid for ATP production - proteolytic enzymes such as prostate specific antigen(PSA) - Acid phosphate - Seminaplasmin which is an antibiotic
How much of semen by volume is produced by the prostate?
25%
How much of semen by volume is produced by the seminal vesicles?
60%
What is the function of the bulbourethral glands?
Secretes clear, mucus-like fluid into the urethra
Describe the bulbourethral glands
Paired glands inferior to prostate on either side of the membranous urethra
Describe benign prostatic hypertrophy
- Enlarged prostate gland(not cancerous)
- numerous nodules compress the prostatic urethra
Benign Prostatic Hypertrophy(BPH) is relatively….
Common in men by age 80
What are the symptoms of benign prostatic hypertrophy?
Numerous nodules compress the prostatic urethra
- weak urination
- difficulty starting and stopping urination
- urgency or feeling to urinate
- frequency to urinate
Prostate cancer is the ….
6th leading cause in cancer deaths in men worldwide
What are the risk factors of prostate cancer?
Age: rare in men below 40 years
- Positive family history
Race: Risk is highest in Afro-Caribbean men and Afro-American men
Risk is intermediate among whites but lowest among Asians
Describe prostate cancer in the early stages
Asymptomatic in early stages
Describe the clinical presentation of prostate cancer
- Asymptomatic in early stages
- when symptomatic, symptoms include:
Poor urinary system
Straining with mictruition
Feeling of incomplete bladder emptying
Terminal dribbling
Symptoms of distant spread(metastasis)
What causes erectile dysfunction in most cases?
Insufficient release of NO which relaxes the smooth muscles of the penile arterioles and erectile tissue
How does viagra enhance smooth muscle contraction?
Increase of NO release
How do parasympathetic fibers play a role in erection (point and shot)?
They initiate and maintain the erection via release of NO to relay smooth muscle of arterioles to relax
Blood vessels dilate,, Einstein are compressed to block blood flow
How do sympathetic fibers assist in erection and ejaculation? (Point and shoot)
Release of semen
Peristaltic contractions propel semen into the penile(spongy) urethra
Contraction of smooth muscle
Decrease blood flow
Decrease blood pressure
Veins open and drain blood
