chapter 27 male and female reproductive Flashcards
1
Q
what is the scrotum?
what does it house?
what is the name when referring to both things together?
A
sack of skin
houses the testes
testicles
2
Q
what is the function of the testes?
A
site of male gametogenesis
3
Q
what is the optimal temperature for spermatogenesis?
A
34 C
4
Q
why are male reproductive organs on the outside of the body?
A
in order to be able to regulate that optimal temperature for spermatogenesis
5
Q
what is the muscle that allows for elevation of testes? what does this do?
A
skeletal muscle called cremaster muscles (which is an extension of internal oblique)
allows for the raising of temperature of the testes
6
Q
what is the muscle that allows for wrinkling of scrotal skin?
what does this do?
A
smooth muscle called dartos muscle
wrinkles scrotal skin to raise temperature of testes
7
Q
what is the structural and functional unit of testes called?
what is the structure within it that forms sperm?
A
lobule (sperm factory)
seminiferous tubules
8
Q
what are the three cells of the testes?
A
Leydig cells
sustenocytes
myoid cells
9
Q
what is another name for Leydig cells?
what is their function?
where are they located?
A
aka interstitial cells
make testosterone
in the space between the seminiferous tubules
10
Q
what is another name for sustenocytes?
what is their function?
where are they located?
A
aka nurse cells
aka Sertoli cells
keep sperm alive while undergoing meiosis
cells that make up wall of seminiferous tubule
11
Q
what is t the function of myoid cells?
where are they located?
A
smooth muscle cells that contract to move sperm through seminiferous tubule
located outside of the seminiferous tubules
12
Q
A
13
Q
A
14
Q
A
15
Q
what is the pathway sperm take once gametogenesis is complete?
A
epididymis -> ductus deferens -> ejaculatory duct -> urethra
16
Q
what is the function of the epididymis?
A
sperm maturation and storage
17
Q
what happens to sperm if not used? how long is it stored for?
A
phagocytosed if not used
stored for several months
18
Q
what structure does the sperm pass through to get to the epididymis from the testes?
A
rete testis (ready testes)
19
Q
how does a vasectomy prevent pregnancy?
A
cut and cauterize or put a band around the ductus deferens which prevents sperm from leaving epididymis
20
Q
A
21
Q
how long does sperm mature in epididymis?
A
20 days
22
Q
A
23
Q
A
24
Q
what is the copulatory organ of males?
A
penis
25
what is the function of the corpus spongiosum?
keeps urethra from collapsing during erection
26
what tissue is most of the penis made of?
corpus cavernosa
27
what are the "legs" of corpus cavernosa tissue that form the base of the penis?
crura
28
what are the three accessory glands that produce secretions for semen? what percentages do each contribute to semen?
seminal vesicles 60%
prostate 20-30%
bulbourethral gland
29
what is the function of the seminal vesicles?
contributes to seminal fluid during ejaculation which is:
- alkaline to help sperm survive acidic vagina
- contains fructose to feed sperm
- contributes to most of semen volume
30
what is the function of the prostate gland?
prostate secretions:
- citrate which acts as buffer and nutrient source
- contains sperm activating enzymes
- contains PSA (prostate specific antigen) which liquifies semen
31
what is benign prostatic hyperplasia?
benign enlargement of prostate that occurs in elderly men which pinches off urethra causing dysuria (no pee) and nocturia (night pee
32
what is prostatic carcinoma? how can it be diagnosed?
second most lethal cancer that has no early symptoms
- digital rectal exam
- PSA screening to see if there's an abundance of PSA
33
what is the function of the bulbourethral gland? what is its other name?
Cowper's gland
pre-ejaculation that is:
- mucus-filled to lubricate urethra
- alkaline to neutralize urine in urethra
34
35
36
37
how is erection regulated?
parasympathetic control
local release of NO causes vasodilation
38
how is ejaculation regulated?
sympathetic control
39
what is the mechanism of action of Viagra?
makes smooth muscle cells more sensitive to NO
improves vasodilation
40
less veins = less blood can leave the penis = more blood flow accumulating in penis
41
what is spermatogenesis? where does it occur?
sperm formation
between sustenocytes (wall of seminiferous tubule)
42
how many sperm is produced by a healthy male per day?
400 million per day until death
43
what are spermatogonium?
stem cells that constantly divide to make cells that will enter meiosis
44
what are type A/B spermatogonium?
type A: remain stem cells (spermatogonia)
type B: become primary spermatocytes that undergo spermatogenesis
45
what is spermeogenesis?
last step of spermatogenesis where spermatids become spermatozoa
* Grow tail
* Lose excess cytoplasm
* Package DNA into small
head
46
how fast does semen travel?
11mph
47
what is spermatozoa?
fully formed sperm
48
what are the three structural regions of a spermatozoan?
head
midpiece
tail
49
what is the structure/function of the head of spermatozoan?
compact nucleus
surrounded by acrosome which contains enzymes that allow sperm to enter egg
50
what is the structure/function of the midpiece of the spermatozoan?
contains mitochondria to provide ATP for swimming
contains cytoskeletal filaments to rotate tail
51
what is the structure/function of the tail of the spermatozoan?
flagellum that propels sperm
52
53
54
draw the full process of spermatogenesis (including spermiogenesis
55
spermatids turning into spermatozoa
56
describe what occurs during spermatogenesis
meiosis and spermiogenesis
57
where does spermatogenesis occur?
between sustenocytes
58
Explain how GnRH, FSH, and LH regulate testosterone production and spermatogenesis
GnRH is released by hypothalamus and travels through to anterior pituitary where it stimulates the release of FSH and LH
LH binds to Leydig cells which stimulates production of testosterone
FSH binds to sustenocytes and stimulates spermatogenesis by telling it to make testosterone receptors
59
what is the effects of testosterone?
- triggers spermatogenesis
- primary male sex hormone
- anabolic effects (like bone and muscle growth)
- increased hair growth
- deepens voice
60
what happens without testosterone in males?
testes atrophy
sperm production ceases
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63
64
what is the structure/function of the ovaries?
- contain many ovarian follicles that house developing oocytes
- promotes female sex hormones
65
what is a Graafian follicle?
mature ovarian follicle
66
describe the layers of the Graafian follicle from deep to superficial
- oocyte in center, with zona pellucida surrounding (sperm have to eat through this layer)
- antrum is fluid filled space outside of oocyte
- granulosa cells around oocyte
- thecal cells form outer layer of follicle
67
is the uterine tube directly connected to the ovary?
no it has an infundibulum that drapes over the ovary
contains cilia which sweeps egg into uterine tube
68
what is the function of the uterine tube?
transport oocyte to uterus by use of cilia and peristalsis
69
what causes an ectopic pregnancy?
why is this bad?
occurs when fertilized egg implants in peritoneum or distal tube
structures lack sufficient vascularization to support growth
70
what is the function of the uterus?
receive, retain, and nourish fertilized egg
71
what are the three layers of the uterine wall from superficial to deep?
perimetrium
myometrium
endometrium
72
what is endometriosis?
endometrium grow on structures other than inside uterus (like uterine tube, ovary, peritoneum)
this can become inflamed
73
what is the female copulatory organ?
vagina
74
what does the vagina have that allows for stretch?
rugae
75
what tissue is the vagina lined with?
stratified squamous cells to withstand friction
76
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78
79
what is an oogonia?
stem cell of an oocyte
80
when does oogenesis occur?
during embryonic development
81
when does oogenesis pause the process?
- at birth pauses at meiosis I as a primary oocyte
- after puberty at meiosis II as a secondary oocyte
82
when does oogenesis continue after stalling the first time?
during puberty a few primary oocyte reactivate
83
what occurs to the oocyte when oogenesis continues after puberty?
asymmetric division occurs and leaves one cell with most of the cytoplasm and another little cell called polar bodies
84
when does an oocyte continue oogenesis after the second pause?
fertilization triggers completion of final cell division
85
why is oogenesis more prone to errors than spermatogenesis is?
because it starts before birth and stalls twice
86
87
explain how its possible for a child to have three parents?
nuclear transfer
baby can have mitochondrial DNA from one parent and two different parents for chromosomal DNA
88
describe the three phases of the ovarian cycle?
follicular phase - follicle grows during oogenesis
ovulation - follicle bursts and oocyte leaves ovary
luteal phase - ruptured follicle becomes endocrine gland
89
when entering the follicular phase, oocytes begin paused in meiosis I within a primordial follicle. what happens to the follicle and oocyte during the follicular phase?
primordial follicle -> secondary follicle -> Graafian follicles
oocyte begins paused at meiosis I but continues to meiosis II where it then pauses again
90
what happens to the follicle during ovulation?
follicle ruptures and releases stalled secondary oocyte (in meiosis II)
91
what happens to the follicle during the luteal phase?
what occurs if pregnant/not pregnant?
ruptured follicle becomes the corpus luteum where it secretes progesterone and estrogen
if no pregnancy = breaks down after 10 days
if pregnant = persists hormone function until placenta takes over
92
what day does each phase of the ovarian cycle occur?
follicular phase: 1-14
ovulation: on day 14 for five minutes
luteal phase: lasts 10 days
93
what is it called when women feel ovulation occur (rupturing of follicle)
mittelschmerz (middle pain - pain in the middle of the cycle)
94
what is it that initiates puberty in girls?
leptin from adipose tissue stimulates GnRH in hypothalamus which stimulates FSH and LH
95
where are the FSH and LH receptors in females?
what do they do?
FSH: in granulosa cells
LH: in thecal cells
stimulate production of estrogen and progesterone
96
what is estrogen and progesterone synthesized from?
androgens
97
what cell type in the ovarian follicle makes androgens and which converts androgens to estrogen?
- thecal cells make androgens when LH binds to its receptor
- granulosa cells convert androgens to estrogen when FSH attaches to receptor
98
what is estradiol?
what is its effect?
one of three forms of estrogen
it regulates uterine cycle
promotes growth and maturation of sex organs during puberty
promotes long bone growth in early puberty
99
what is the general trend of estrogen and progesterone levels in the blood during the different phases of the ovarian cycle?
follicular phase: day 1-6 slow gradual increase
day 6-14: initially low, but then surge to trigger ovulation
ovulation: levels plummet but then begin to rise
luteal phase: corpus luteum triggers abundant release but towards the end, they fall again
100
what is the blood concentration of LH and FSH like during the phases of the ovarian cycle
spike dramatically only at ovulation (LH more so)
is triggered by abundance of estrogen and progesterone at this time
101
List the three phases of the uterine cycle
menstrual
proliferative
secretory
102
what occurs during the menstrual phase? how long is it?
what triggers it?
day 1-5: uterus sheds all but deepest layer of endometrium
triggered by drop in estrogen and progesterone
103
what occurs during the proliferative phase?
how long is it?
what triggers it?
day 6-14: endometrium rebuilds itself
stimulated by rising levels of estrogen
104
what occurs during the secretory phase?
how long is it?
what triggers it?
day 15-28: endometrium secretes nutrients to prepare for implantation
triggered by increased progesterone increasing blood supply
105
when do female fertility rates decline?
how many oocytes at age 30?
age 50?
between 30-40 years
100 k
3
106
what happens when estradiol levels drop in women?
ovaries atrophy
107
what happens to cause menopause?
what age?
when is it official?
- as fewer follicles mature, estrogen and progesterone levels decrease
- 46-54
- 12 months after no menstruation
108
what are symptoms of menopause?
- increased risk of cardiovascular disease
- osteoporosis (osteoblasts die in absence of estrogen)
- weight gain
- mood swings
109
how can we reduce menopause symptoms?
hormone replacement therapy (short term)
Phytoestrogens (plant-based estrogen-like)
110
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112
113
what is progestin? where is it found?
synthetic progesterone found in birth control pills
114
what is the most common form of birth control pill
combination pills made of progestin and estrogen
115
what is the mini-pill?
contains only progestin (is safe to take during pregnancy)
116
what is the mechanism of birth control?
inhibits ovulation by maintain increased levels of progesterone and estrogen which inhibits FSH and LH release
117
how does the morning after pill work?
contains loads of progesterone which:
- increases viscosity of cervical mucus = reduced sperm motility
- alters endometrial lining (makes implantation difficult)
118
what is withdraw bleeding?
week of placebo pills in birth control where sudden drop in estrogen and progesterone trigger menstruation and skip ovulation
119
what is mifepristone used for?
blocks progesterone receptors which mimics the drop in progesterone levels which triggers endometrium to shed as if no fertilization occurred
120
when is mifepristone effective?
first 7 weeks of pregnancy
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