Male Reproductive System - Exam 4 Flashcards
What is the primary sex organ?
gonads
What do the gonads produce?
gametes (sperm, eggs)
sex hormones
What are the accessory reproductive organs?
ducts
glands
external genitalia
What is the scrotum?
sac of skin that hands outside of the abdominal cavity containing testes
What is the scrotum functionally involved in?
protection
acts as a climate control system for testes
The movement of the scrotum is driven by which two muscles?
- dartos muscle
- cremaster muscles
What is the dartos muscle responsible for?
smooth muscle that wrinkles up when cold to keep the testes at a constant temperature
What is the cremaster muscle responsible for?
surrounding the testes and spermatic cord, which suspends the testes
What are the two things that supply blood to the testes?
testicular arteries
testicular veins
What is the technical name for testicular veins?
pampiniform plexus
How does the pampiniform plexus aid in temperature regulation?
cools blood in adjacent arteries
Explain the anatomy of the testes
testes separated into 250 segments containing 1-4 seminiferous tubules
What is the function of the seminiferous tubulues?
sperm production
produce testicular fluid to aid in production
What are the seminiferous tubules surrounded by?
3-5 layers of smooth muscle-like cells
What cells in the testes produce and secrete androgens?
interstitial cells
When do sperm mature?
mature as they travel along the duct of the epididymis
How long does sperm maturation take?
20 days
Where can sperm be stored and how long?
stored in epididymis for several months
How is sperm propelled and where is it propelled during ejaculation?
smooth muscle within duct constricts, propelling sperm into vas deferens
What does the vas deferens contain that also propels sperm during ejaculation?
thick smooth muscle layer
What happens during a vasectomy?
vas deferens are split
Describe the inner-workings of the male reproductive duct system
loops over pubic bone
joins with duct of seminal gland
connects to prostatic urethra through ejaculatory duct
Semen
milky, white somewhat sticky mixture of all substances secreted by testes and glands
How much sperm does semen contain?
40-750 million
What does the seminal gland secrete?
seminal fluid
Seminal fluid accounts for 70% of what?
the contents of semen
Describe seminal fluid
secretes a yellowish alkaline fluid that has stuff that
- enhances sperm motility
- provide energy for sperm
- coagulates semen in vagina
- suppresses female immune system
What does the prostate encircle?
prostatic urethra
What does the prostate secrete?
milky, slightly acidic fluid that activates sperm, liquefies coagulated semen, and stabilizes DNA in sperm
What does the bulbourethral glands secrete?
thick, clear mucus into spongy urethra for lubrication during ejaculation
The mucus secreted by the bulbourethral glands does what to urine in the urethra?
neutralizes it
An erection is caused by blood flow into what?
corpus cavernosa
spongiosum
What happens to the surrounding arterioles during arousal?
they dilate
An erection is initiated by?
mental and sensory stimulation, relaxation of corpus cavernosa which allows for blood flow in
What sustains an erection?
tunica albuguinea traps blood in corpus cavernosa
When a climax is reached, a sympathetic nervous system signal initiates what?
- constriction of sphincter in bladder
- contraction of smooth muscle in accessory glands and ducts
- rapid series of contractions of the bulbospongiosus muscles
The male orgasm is followed by?
resolution (relaxation) then a refractory period (unable to reach another orgasm)
When does spermatogenesis start?
14 years old
Spermatogenesis produces how much sperm per day?
400 million
Sperm formation occurs through what?
meiosis
