module 9 Flashcards
what does the parasympathetic devision control in the penis
- blood vessels dilate
- Increased blood flow to penis
- Vascular channels become engorged with blood
- Erection of penis
what does the sympathetic nervous system control in the penis
ejaculation
what does the scrotum do
- houses the testies
- composed of the darts and cremaster muscele which maintain optimal temperature (34) for the production of sperm
whats the functions of the epididymis
- stores, nourishes and protects spermatozoa
- Facilitates functional maturation
- Recycles damaged sperm
- Ejaculates the sperm to vas deferens
the travel of sperm
Epididymis ductus/vas deferens Ejactulatory ducts Urethra (total 66 meters) Secretions are added the sperm by seminal vesicles, prostate
whats the ductus deferens
transport sperm from the epididymis to the ejaculatory duct.
whats the seminal vesicle
produces seminal fluid which makes up 60-70% of semen volume and contains substances that enhance sperm mobility and their ability to fertilise an ovum.
whats the ejaculatotry duct
transports sperm through the prostate gland to the urethra.
prostate gland
doughnut shaped gland, surrounded by urethra and produces 30% of semen volume
whats the bulbourethral glands
produces a thick mucous that lubicates the glans of the penis
whats the testes contain
interstitial cells which produce and secrete testostorne
seminiferous tubules which produce sperm
whats the process of production of sperm
Spermatogenesis
occurs in the seminiferous tables of the testse
Begins at approximately 14 years of age
Results in 400 million new sperm per day
Sperm take 10 weeks to make
Meiosis
Gametes contain 23 chromosomes (one of each pari)
whats the structure of sperm
Head: genetic region, nucleus and a vesicle containing enzymes that enable the sperm to penetrate an ovum
Midpiece: metabolic region, mitochondria= energy production
Tail: locomotor region, flagellum= movement
what does semen consist of
Epididymal secretions (fluid and sperm) 5%
Seminal vesicle secretions 60%
Prostate secretions 30%
Bulbourethral secretions 5%
whats the HPG hypothalamic pituitary gonadal axis steps
The hypothalamus releases gonadotropin-releasing hormone (GnRH)
GnRH signals the release of follicle stimulating hormone (FSH) and
luteinizing hormone (LH) from the anterior pituitary
FSH stimulates sustenocytes (Sertoli cells) in the seminiferous tubules to produce androgen-binding protein (ABP) which concentrates testosterone
LH stimulates interstitial (Leydig) cells in the seminiferous tubules to produce testosterone
Concentrated testosterone drives spermatogenesis
Increased testosterone levels negatively feed back to inhibit GnRH and FSH/LH release
Inhibin is also produced during spermatogenesis and has negative feedback effects on FSH and GnRH
what does testosterone do
stimulates spermatogenesis
Increases growth of reproductive glands and cuts
Increases size of penis
Enhances ability to maintain erection
Stimulates male secondary sex characteristics
whats male secondary sex characteristic include
Pubic, axillary and facial hair – Enhanced hair growth on chest and other areas – Deepening of voice – Increased skeletal and muscle mass – Increases metabolism rate – Influences behaviour