4_5MaleReproductive Flashcards
1
Q
How much of semen is contributed by the prostate?
A
30%
2
Q
How much of semen is contributed by the seminal vesicles?
A
60%
3
Q
Describe the characteristics of prostate gland secretions?
A
thin, milky, and slightly alkaline
4
Q
What are the contents of prostate gland secretions?
A
1) clotting factors; 2) profibrinolysin; 3) ca, citrate, po4
5
Q
pH of vas deferens
A
3.5-4
6
Q
pH of vagina
A
3.5-4
7
Q
pH at which sperm motility is active?
A
6+
8
Q
What is the function of prostate gland secretion?
A
activating sperm motility
9
Q
What are the components of seminal vesicle secretions?
A
1) fibrinogen, 2) alkali, 3) fructose, citric acid, nutrients; 4) PGs
10
Q
What is the function of PGs of semen?
A
1) receptive cervical mucous for good motility; 2) reverse peristalsis in uterus and fallopian tubes
11
Q
How much of semen is contributed by the bulbourethral glands?
A
5%
12
Q
What are the components of the bulbourethral secretions?
A
mucous (right before ejaculation) for neutrilizing pH of urethra/vagina
13
Q
What are the accessory glands of the male repro system?
A
1) prostate, 2) seminal vesicles, 3) bulbourethral glands
14
Q
Where does spermatogenesis occur?
A
seminiferous tubule
15
Q
Where does spermiogenesis occur?
A
rete testis
16
Q
What are the 3 phases of the male sex act?
A
1) erection, 2) lubrication, 3) emission and ejaculation
17
Q
Describe the structure of sperm
A
head, neck, body, tail
18
Q
What is the function of the acrosome?
A
supply of hyaluronidase and proteolytic enzymes
19
Q
What is the function of the sperm body?
A
rich in mitochondria for motility
20
Q
What is the function of the tail?
A
corkscrew movement for propulsion
21
Q
Describe the composition of the sperm tail.
A
microtubules
22
Q
Where do sperm mature?
A
epididymis
23
Q
Where are mature sperm stored?
A
vas deferens
24
Q
How long do sperm live in the female tract?
A
1-2 days
25
How fast do sperm move?
1-4 mm/min
26
What is the zona pellucida?
granulosa cells surrounding the ovum
27
When and for how long does male puberty occur?
9-14 yo lasting 2-4.5 years
28
What is the first sign of male puberty?
testes enlargement (2.5+ cm)
29
Where is inhibit secreted?
sertoli cells
30
How long does spermiogenesis take?
21 days
31
Describe the timeframe and production rate of spermatogenesis.
constant 74 day process making 10^8 spermatids per day
32
What is spermiogenesis?
the change from spermatid to spermatozoa
33
How long does it take for a spermatozoa to mature in the epididymis and gain motility?
18-24 hours
34
What is the corpus spongiosum?
spongy tissue surrounding the urethra
35
What is the corpus cavernosum?
there are 2 cavernosa that surround central arteries
36
What occurs during the erection phase?
parasympathetic system dilates erectile tissue
37
What occurs during the lubrication phase?
parasympathetic system stimulates urethral and bulbourethral mucous secretions
38
What occurs during emission?
sympathetic stimulation causes 1) vas deferens contracts to propel sperm into urethra; 2) seminal glands and prostate empty and mix with mucous
39
Where does capacitation occur and why does it occur?
in vagina; required for mature sperm to be able to fertilize
40
How is the zona pellucida held together?
hyaluronic acid
41
Describe the steps in the acrosomal reaction.
1) sperm binds specific zona pellucida receptors; 2) acrosome membrane dissolves to release enzymes; 3) pathway for fertilization opened; 4) blockage to polyspermy
42
Describe the steps in capacitation.
1) fibrinogen clot near cervix digested by slow-acting fibrinolysin; 2) loss of inhibitory factors from male; 3) depletion of acrosomal cholesterol; 4) increased membrane Pe to Ca++ increases flagellum activity and initiates acrosome reaction
43
What happens when the sperm's membrane becomes more permeable to Ca++ during capacitation?
increased tail activity and initiation of acrosome reaction
44
How long does it take for fibrinolysin to act?
15-30 min
45
What causes the clot near the cervix?
fibrinogen + prostate's clotting factors
46
Where is gonadal testosterone synthesized?
leydig cells
47
How does testosterone circulate in the plasma?
bound to sex steroid binding globulin
48
Describe the circulating [testosterone] over lifetime.
high in fetal/neonatal patients for 1 year; then peak in puberty and decline at 50 yo
49
What is the most active form of testosterone?
dihydrotestosterone (DHT)
50
How is testosterone excreted?
converted to weak androgens or glucuronidated/sulfated then peed out
51
What is the fate of testosterone in tissues?
converted to DHT by 5-alpha-reductase
52
What causes testical enlargement in puberty?
trophic effects of FSH and LH on seminiferous tubules and Leydig cells
53
When is inhibin secreted?
when spermatogenesis rate is fast
54
What is the effect of FSH?
acts on sertoli cell to stimulate spermatogenesis
55
What is the effect of LH?
acts on Leydig cell to stimulate testosterone synthesis
56
What kinds of hormones are LH/FSH?
glycoproteins
57
What are the effects of testosterone?
binds androgen receptor to: 1) cause primary sex characteristics and testical descent (3rd trimester) in fetus; 2) cause secondary sex characteristics; 3) increase BMR; 4) increase BMR
58
What is the concentration of RBCs in males?
700,000/mL
59
What do Sertoli cells do?
nursemaid cells that support spermatogonia (spermatogenesis) and secrete inhibin
60
Describe feedback regulation of the HT-Pituitary-Testicular axis.
1) testosterone: -AP, -HT, +Sertoli (inhibin); 2) inhibin: -AP, -HT
61
To which receptors to LH/FSH bind?
G-alpha-s
62
What is andropause?
a slow decline in 2ndary sex characteristics beginning in 40s and 50s; LH constant but FSH increases with aging
63
What are causes of premature ejaculation?
anxiety and learned behavior
64
What are treatments for premature ejaculation?
BMOD, SSRIs
65
In what population is ED most prevalent?
40-70 years (52%)
66
What are causes of ED?
1) vascular disease, 2) radiation/surgery for prostate cancer, 3) spinal cord injury, 4) stress, 5) drugs
67
What drugs can cause ED?
diuretics, antidepressants, antilipidemics, antihypertensives, tranquilizers, hormones, EtOH, cocaine, marijuana
68
What drugs treat ED?
sildenafil, tadalafil, vardenifil
69
When are PD5-I's C/I?
recent MI or stroke since PDE-5 is in heart
70
What are ADRs of PDE5-I's?
congestion, flushing, dizziness, dyspepsia
71
What is eunichism?
loss of testes before puberty
72
What is hypogonadism?
when a non-functional testes during fetal life gives no primary sex characteristics
73
What are causes of hypogonadism?
1) eunichism, 2) castration after puberty, 3) hypothalamic eunichism
74
What is benign prostatic fibroadenoma?
BPH leading to urinary obstruction NOT caused by testosterone
75
What are the two types of testicular cancers?
1) interstitial cell tumor, 2) germinal epithelial tumor
76
Describe the development of prostate cancer.
Initiation somehow, then testosterone causes rapid growth
77
Which testicular cancer is more common?
germinal epithelial tumor
78
How is an interstitial cell tumor diagnosed?
quick sexual development in children; hard to tell in adults
79
What is a teratoma?
a tumor of many types of cells (totipotent)
80
Though uncommon, what hormones can be secreted by a germinal epithelial testicular tumor?
hCG (if placental tissue develops), or estrogen (causing gynecomastia)
81
What are the reactions behind erection?
1) L-Arg -- NO + citrulline (via NOS); 2) GMP -- cGMP (via guanylate cyclase); 3) cGMP -- GMP (via PDE5)
82
How does cGMP give an erection?
relaxes smooth muscle in the corpus cavernosa
83
How is guanylate cyclase activated?
NO
84
How is male infertility diagnosed?
1) less than 20 million sperm/mL; 2) or, less than 40% motility; 3) or, less than 40% normal morphology
85
What are the causes of male infertility?
1) anabolic steroid use, 2) STDs, chemo/radiation; 3) viral orchitis/mumps; 4) low testosterone (hypogonadism or hypopituitarism)
86
What are the various methods for male birth control?
1) vasectomy, 2) hormonal, 3) immunocontraception
87
Is vasectomy reversible?
yes, unless interstitial fibrosis of the testes occurs
88
Describe hormonal contraception.
In europe, testosterone and progestagin yielded azospermia in 6-8 weeks
89
What are the various types of immunocontraception?
1) vaccines that target gamete production via hormones; 2) vaccines that target gamete function via zona pellucida and sperm; 3) vaccines that target gamete outcome via hCG
90
When do the seminal vesicles empty?
right after the sperm go through
91
What is needed to stimulate spermatogenesis?
GH stimulates; but LH also required
92
What happens at birth regarding spermatogenesis?
primordial germ cell enters testis to become spermatogonia
93
What happens at puberty regarding spermatogenesis?
spermatogonia migrate toward lumen among Sertoli cells and spermatogenesis is triggered
94
How can prostate cancer be inhibited?
estrogens or testicle removal (both indicate carcinoma of the prostate)
95
What factors give a false positive for PSA?
inflammation of the prostate
96
When does PSA no work?
if PSA less than 2 and no lesions by digital exam - 30% still had carcinoma
