Exam 5 - Male Reproductive System Flashcards
What do the primary sex organs do?
Produce gametes so testes or ovaries
What are secondary sex organs?
Organs other than gonads that are necessary for reproduction
What are the secondary sex organs of males?
System of ducts, glands; penis delivers sperm cells
What are secondary sex characteristics?
features that distinguish the sexes and influence mate attraction; developed at puberty
What are the secondary sex characteristics of both sexes?
Pubic and axillary hair and their associated scent glands, and the pitch of the voice
What is the secondary sex characteristics of males?
Facial hair, coarse and visible hair on the torso and limbs, relatively muscular physique
What is the perineum?
Diamond-shaped area between thighs
Where is the spermatic cord?
Connects testes into pelvic cavity
What are cremaster muscles and what do they do?
Strips of the internal abdominal oblique muscle; contracts in cold temp and relaxes in warm temp
What are dartos muscles?
Subcutaneous layer of smooth muscle that also contracts when cold and reduces surface are for heat loss
What are pampiniform plexus?
Extensive network of veins that removes heat from descending arterial blood
What are the testes?
Combined endocrine and exocrine glands that produce sex hormones and sperm
What is the tunica albuginea?
White fibrous capsule on testes
What are seminiferous tubules?
Ducts where sperm are produced
What line the seminiferous tubules?
Sustentacular cells between germ cells and interstitial cells between tubules
What is the blood-testis barrier(BTB)?
Tight junctions between sustentacular cells; separate sperm from immune system
What are the rete testis?
Network on the posterior side of the testis that collects sperm from seminiferous tubules
What are efferent ductules?
Ciliated ducts collecting sperm from rete testes to epididymis
What happens at the duct of epididymis?
Sperm maturation and storage
What is the seminal vesicles and what do they do?
Pair of glands that empties into ejaculatory duct; forms 60% semen
What is the prostate gland and what does it do?
Surrounds urethra and ejaculatory duct; thin milky secretion forms 30% of semen
What are the bulbourethral glands and what do they do?
Near bulb of penis; produce clear slippery fluid and protects sperm by neutralizing the acidity of urine
What is prostate cancer?
Tumor near periphery of the gland that does not obstruct urine flow
Where is the digital rectal exam?
Palpated through rectal wall to check for tumors
Where is the corpus spongiosum?
Ventral side of penis that encloses urethra
Where are the corpora cavernosa?
The other side of the penis that diverge like a Y
What leads to the onset of puberty?
Surge of pituitary gonadotropins
What is adolescence?
Period from onset of gonadotropin secretion
What is puberty?
The first few years of adolescence until first menstrual period in girls or first ejaculation of viable sperm in boys
When do testes secrete testosterone?
First trimester of fetal development
What does GnRH secrete when stimulated?
FSH and LH
What does FSH do in men?
Stimulates sustentacular cells to secrete androgen-binding protein that binds testosterone
What does LH do in males?
Stimulates interstitial cells to produce testosterone
What happens during puberty of males?
Growth of sex organs such as penis, testes, and scrotum; stimulates sperm production and libido (sex drive)
What does testosterone do during males puberty?
Stimulates generalized body growth
What does DHT do during puberty?
Causes pubic hair, axillary hair, and facial hair
What happens during adulthood for men?
Inhibin from sustentacular cells suppress FSH output; reducing sperm production without reducing LH and testosterone secretion
What are the hormonal steps in men?
1) GnRH from the hypothalamus stimulates to secrete FSH and LH
2) FSH stimulates sustentacular cells to secrete ABP
3) LH stimulates interstitial cells to secrete testosterone
4) In presence of ABP, testosterone stimulates spermatogenesis
5) Testosterone stimulates libido and the development of secondary sex organs
6) Testosterone has negative feedback that reduces GnRH
7) Sustentacular cells also secrete inhibin that inhibits FSH secretion reducing sperm production
What are the two parts of spermatozoon?
Head and tail
What are the parts of the head of a spermatozoon?
Nucleus, acrosome (contains enzymes to penetrate the egg), and basal body
What are the parts of the tail of a spermatozoon?
Midpiece (contains mitochondria and produces ATP), Principal piece, and endpiece
What does semen consist of?
60% seminal vesicle fluid, 30% prostatic fluid, and 10% sperm
What does the prostate fluid consist of?
Calcium, citrate, and phosphate ions
What does the seminal vesicles semen consist of?
Fructose and other carbohydrates, and proseminogelin
What causes semen to be sticky?
Clotting enzyme from prostate activates proseminogelin which converts it to seminogelin
How does semen become non-sticky?
Serine protease from prostatic fluid breaks down seminogelin, and liquifies it
