Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Block 4 - OBGYN > A+P: Reproduction II > Flashcards

A+P: Reproduction II Flashcards

1
Q

Define spermatogenesis.

A

process of forming male gametes via meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where does spermatogenesis occur?

A

seminiferous tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When does spermatogenesis occur?

A

at puberty, around 14 years old

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Males make about how much sperm daily?

A

~90 million sperm daily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Seminiferous tubules consists of a thick ___ surrounding a central fluid-filled lumen containing four important types of cells: Name the cells.

A
  • stratified epithelium
    1. Sustentocytes (Sertoli cells)
    2. Spermatogenic cells
    3. Myoid cells
    4. Interstitial endocrine cells (Leydig cells)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Function of sustentocytes (Sertoli cells)

A
  • Blood-testes barrier
  • supporting cells; help w/ sperm production
  • also provide nutrients & signals to dividing cells
  • move sperm cells & spermatids along lumen & secrete testicular fluid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Function of Spermatogenic cells

A
  • surrounded by sustentocytes & dividing to give rise to sperm cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Function of myoid cells

A
  • SM-like cells surrounding seminiferous tubule - contract to squeeze sperm & testicular fluid through tubules/epididymis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Function of insterstitual endocrine cells (Leydig cells)

A
  • Produce androgens & some estrogen
  • creates testosterone to help drive this process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

3 steps of spermatogenesis

A
  1. Mitosis of spermatogonia (stem cell) forms two spermatocytes
  2. Meiosis: spermatocytes form 2ndary spermatocytes, which form spermatids
  3. Spermiogenesis: spermatids become sperm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When does mitosis of spermatogonia begin?

A

at puberty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

After puberty in males, each division via mitosis produces:

A
  • Type A daughter cells
  • Type B daughter cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe Type A daughter cells?

A

remain at basal lamina to maintain pool of dividing germ cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe Type B daughter cells?

A

move toward lumen & develop into primary spermatocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the process of Meiosis: spermatocytes to spermatids–> Meiosis I

A

Primary spermatocyte (2n) undergoes meiosis I, forming two secondary spermatocytes (n)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the process of Meiosis: spermatocytes to spermatids–> Meiosis II

A

2ndary spermatocyte (n) rapidly undergoes meiosis II to become two spermatids (n)
–>Spermatids: small, round cells w/ large nuclei found close to lumen of tubule
–> Nearly all genes are turned off and DNA compacted into dense pellets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe process of Spermiogenesis: spermatids to sperm

A
  • Spermatids contain correct haploid chromosome # needed for fertilization (n)
    –> Are still nonmotile
  • Spermiogenesis
    –> Streamlining process where spermatid elongates, loses excess cytoplasm & forms a tail.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the major regions of sperm?

A

head, midpiece & tail

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe the sperm head.

A

genetic region
- includes nucleus & helmetlike acrosome containing hydrolytic enzymes that enable sperm to penetrate egg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Describe the sperm midpiece.

A

metabolic region containing mitochondria that produce ATP to move tail

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Describe the sperm tail.

A

locomotor region that includes flagellum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How longs does spermatogenesis take?

A

64-72 days (in good conditions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where does the final maturation of sperm occur?

A

epididymis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Define infertility

A

lack of pregnancy after trying a year of unprotected intercourse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Infertility affects how many couples in America?

A

1 in 7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the usual causes of infertility?

A

problems w/ sperm quality or quantity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Possible causes for infertility

A
  • environmental toxins
  • phthalates (in plastics)
  • pesticides
  • herbicides
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are some other poss causes of infertility?

A
  • Estrogen-like compounds block action of male sex hormones
  • Abx (tetracycline may suppress sperm formation)
  • Radiation, lead, marijuana, and excessive alcohol
  • Defects in Ca+ channels, hormonal imbalances & oxidative stress
  • Thermal related events (hot tubs) may inhibit sperm maturation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is a Mittelschmerz?

A

twinge of pain sometimes felt at ovulation by some women
–> scar tissue stretching from previous ovulations??

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Production of gametes and sex hormones is regulated by sequence of hormonal events involving the ___, ___, & ___. aka?

A
  • hypothalamus, anterior pituitary gland, and testes
  • hypothalamic-pituitary-gonadal (HPG) axis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What happens to the remaining granulosa cells and thecal cells during the luteal phase?

A

they enlarge to form corpus luteum that secretes progesterone & estrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What interacting hormones are involved w/ male reproductive physiology?

A
  • GnRH
  • FSH
  • LH
  • testosterone
  • inhibin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Sequence of regulatory events: Male Reproductive Physiology (7)

A
  1. Hypothalamus releases (GnRH)
  2. GnRH binds to ant pituitary gonadotropic cells, causing them to secrete: FSH & LH
  3. FSH stimulates spermatogenesis indirectly by stimulating sustentocytes to release androgen-binding PRO (ABP)
    –> ABP keeps [] of testosterone high near spermatogenic cells, promoting spermatogenesis
  4. LH binds to interstitial endocrine cells, prodding them to secrete testosterone
    –> Rising testosterone levels trigger spermatogenesis
  5. Testosterone entering blood stimulates sex organ maturation, development/maintenance of 2ndary sex characteristics & libido
  6. Rising testosterone levels feed back on hypothalamus to inhibit GnRH & on pituitary to inhibit gonadotropin release
  7. Inhibin: released by sustentocytes when sperm count high; inhibits GnRH & FSH release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

NOTE

A
  • Before birth, male infant has testosterone levels 2/3s of adult
  • After brief rise in early infancy, blood levels recede & remain low through childhood
  • As puberty nears, higher levels of testosterone are required to suppress hypothalamic release of GnRH & adult pattern is established
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

NOTE

A

Amount of testosterone & sperm produced by testes reflects balance among interacting hormones of HPG axis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What long does it take for testosterone & sperm production to stabilize?

A

3 years and then stable throughout life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Without GnRH & gonadotropins what happens?

A
  • testes atrophy
  • sperm & testosterone production ceases
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is testosterone synthesized from?

A

cholesterol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Testosterone is converted to what in the prostate?

A

dihydrotestosterone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Testosterone is converted to what in some brain neurons?

A

estradiol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are the 2 functions of testosterone?

A
  • Prompts spermatogenesis & targets all accessory organs
  • Has multiple anabolic effects throughout body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Testosterone def. can lead to:

A
  • atrophy of accessory organs
  • semen volume declines
  • erection/ejaculation impairment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is the tx for testosterone def.?

A

testosterone replacement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What are male secondary sex characteristics?

A

features induced in nonreprod. organs by male sex hormones (mainly testosterone)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

List some male sex characteristics.

A
  • pubic, axillary & facial hair
  • hair on chest
  • larynx enlargements–> deep voice
  • skin thickens & becomes oily
  • Bones grow, incr in density
  • Skeletal muscles incr size & mass
  • Boosts BMR
  • Basis of sex drive (libido)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

When does oogenesis begin?

A

in fetal period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Describes the steps of oogenesis.

A

Oogonia (diploid stem cells) divide by mitosis to produce:
Primary oocytes that undergo meiosis I to produce:
Secondary oocytes that undergo meiosis II to produce:
Ova

46
Q

What are the 3 key differences b/t oogenesis & spermatogenesis?

A
  1. Production of primary oocytes occurs only fetus
  2. In primary oocytes, meiosis is arrested in late prophase I & resumes only years later (if at all)
  3. In secondary oocytes, meiosis is arrested in metaphase II & is only completed if fertilization occurs
47
Q

What are the fates of follicles?

A

atresia or ovulation

48
Q

Describe atresia.

A

apoptosis (programmed cell death) of oocyte & surrounding cells
99.9% of all follicles are never recruited

49
Q

Describe ovulation (more specific)

A
  • Each month after puberty, a select few primary oocytes are activated
  • Caused by high hormonal levels, especially FSH
  • 1 from this group is “selected” each month to become dominant follicle
50
Q

of gametes per lifetime for males

A

> 1 trillion

51
Q

of gametes per lifetime for females

A

<500

52
Q

What cells sustains spermatocytes?

A

sustentocytes

53
Q

What cells sustains oocytes?

A

granulosa cells

54
Q

Number of functional gametes differ: Oogenesis vs Spermatogenesis

A
  • Oogenesis produces 1 viable haploid ovum w/ 2-3 haploid polar bodies
  • Spermatogenesis produces 4 viable sperm
55
Q

Occurrence during lifetime: Oogenesis vs Spermatogenesis

A
  • Oogenesis begins in fetal life, ends in menopause
  • Spermatogenesis begins in puberty to old age (80s)
56
Q

Why is the error rate higher in females?

A

b/c they are sitting in that “frozen” state for so long

57
Q

Describe the ovarian cycle.

A

montly (28-day) series of events assoc. w/ maturation of egg

58
Q

Describe the two phases of the ovarian cycle?

A

follicular & luteal

59
Q

NOTE

A

2 consecutive phases w/ ovulation occurring midcycle (~ day 14-15) b/t phases

60
Q

What is the follicular phase?

A

period of vesicular follicle growth
- days 1-14

61
Q

Describe what’s happening during the follicular phase?

A
  • the follicle is undergoing development caves in which the ova are kept
  • 5-10 will grow in one ovary. They will alternate which ovary has the growing ova
62
Q

What is the luteal phase?

A

period of corpus luteum activity
- days 14 - 28

this is what’s happening inside the ovary

63
Q

What phases vary and which stay the same? Describe.

A
  • follicular phase varies
  • luteal phase is always 14 days from ovulation to end of cycle
64
Q

What happens during the follicular phase?

A

several follicles become sensitive to FSH & are stimulated to grow

65
Q

What happens around the middle of the follicular phase?

A

FSH levels drop

66
Q

What happens to non-dominant follicles?

A

atresia (breakdown)

67
Q

Describe ovulation.

A

ballooning ovary wall ruptures, expelling into peritoneal cavity

68
Q

When does fraternal twins occur? Explain.

A

ovulation releases >1 2ndary oocyte
–> if fertilized = fraternal twins

69
Q

When does identical twins occur? Explain.

A
  • after fertilization
    –> fertilization of 1 oocyte, then separation of daughter cells
70
Q

Can oocytes be released at times unrelated to hormone levels?

A

YES

71
Q

What happens during the luteal phase of ovarian cycle?

A

After ovulation, ruptured follicle collapses & antrum part of the follicle fills w/ clotted blood
- Referred to as corpus hemorrhagicum; will eventually be absorbed

72
Q

What happens if NO pregnancy does occur during the luteal phase?

A

corpus luteum degenerates into corpus albicans (scar) in 10 days

73
Q

What is the luteolytic or ischemic phase?

A

last 2–3 days of luteal phase, when endometrium begins to erode

74
Q

What happens if pregnancy does occur during the luteal phase?

A

corpus luteum produces hormones that sustain pregnancy until placenta takes over at about 3mos

75
Q

Function of estrogen & progesterone during the luteal phase?

A

working on the uterus
- getting it ready for a fertilized egg

76
Q

What makes beta-hCG?

A

the fertilized ovum

77
Q

What is Beta-hCG?

A

marker to the corpus luteum to maintain the lining of the uterus

78
Q

Which phase do miscarriages usually occur?

A

Luteal phase of ovarian cycle

79
Q

How long does hormonal regulations occur for establishing ?hormonal regulation continue?

A

until an adult cycle pattern in achieved and menarche occurs

80
Q

What is the average age of menarche?

A

11-12 yo

81
Q

List 6 key steps of hormonal interaction during ovarian cycle

A
  1. GnRH stimulates FSH & LH secretion
  2. FSH & LH stimulate follicles to grow, mature & secrete sex hormones
  3. Neg feedback inhibits gonadotropin release
  4. Pos feedback stimulates gonadotropin release
  5. LH surge triggers ovulation & formation of the corpus luteum
  6. Neg feedback inhibits LH & FSH release
82
Q

Describe how GnRH stimulates FSH & LH secretion.

A

the pulsatile release tells the ant pituitary which hormone will be released

83
Q

Describe how FSH & LH stimulate follicles to grow, mature & secrete sex hormones

A
  • FSH stimulates the release of estrogen
  • LH stimulate the production of androgens, which are converted to estrogens
84
Q

Describe how neg feedback inhibits gonadotropin release.

A

Incr levels of plasma estrogen levels exert neg feedback inhibition on FSH & LH release

  • only 1 dominant follicle can withstand the dip in FSH; other developing follicles deteriorate
85
Q

What is inhibin?

A

a hormone released by the granulosa cells of the ovaries that also inhibits FSH release

86
Q

Describe how pos feedback stimulates gonadotropin release in women

A
  • Estrogen levels cont. to rise as a result of continued release by dominant follicle
  • When levels reach a critical high value, a brief pos feedback occurs on brain & anterior pituitary
  • Triggers LH surge
87
Q

Describe how LH surge triggers ovulation & formation of the corpus luteum.

A
  • High estrogen levels trigger release of stored LH, by anterior pituitary at midcycle
  • Surge triggers ovulation
88
Q

What happens shortly after ovulation?

A
  • Estrogen levels decline
  • LH transforms ruptured follicle into corpus luteum
  • LH stimulates corpus luteum to secrete progesterone & some estrogen almost immediately
    –> Progesterone helps maintain stratum functionalis of the endometrium
    –> Maintains pregnancy, if it occurs
89
Q

Describe how neg feedback inhibits LH & FSH release

A
  • Neg feedback from rising plasma progesterone & estrogen levels inhibits LH & FSH release
    –> Inhibin, from corpus luteum & granulosa cells, enhances inhibitory effect
    –> Declining LH ends luteal activity & inhibits follicle development (& therefore starts degradation)
90
Q

Describe the uterine menstrual cycle.

A

cyclic series of changes in endometrium that occur in response to fluctuating ovarian hormone levels

91
Q

What are the 3 phases of the menstrual cycle?

A
  • Days 1–5: menstrual phase
  • Days 6–14: proliferative (preovulatory) phase
  • Days 15–28: secretory (postovulatory) phase
92
Q

What occurs during the menstrual phase?

A
  • Ovarian hormones are at lowest levels
  • Gonadotropin levels are beginning to rise
  • Stratum functionalis detaches from uterine wall & is shed
    Menstrual flow of blood & tissue lasts 3–5 days
  • By day 5, growing ovarian follicles start to produce more estrogen
93
Q

What occurs during the proliferative (preovulatory) phase?

A
  • ^^ estrogen levels prompt generation of new stratum functionalis layer
    –> As layer thickens, glands enlarge, & spiral arteries incr in #
  • Estrogen increases synthesis of progesterone receptors in endometrium
  • Thins out normally thick, sticky cervical mucus to facilitate sperm passage
  • Ovulation occurs at end of proliferative phase on day 14
    starts rebuilding of the uterine lining
94
Q

What occurs during the secretory (postovulatory) phase?

A
  • Phase that is most consistent in duration
  • Endometrium prepares for embryo to implant
  • Rising progesterone levels from corpus luteum prompt:
    –> Functional layer to become a secretory mucosa
    –> Endometrial glands enlarge & secrete nutrients into uterine cavity
    –> Thickened mucus to form cervical mucus plug - blocks entry of more sperm, pathogens, or debris
95
Q

Describe what happens if fertilization doesn’t occur during the secretory phase?

A
  • Corpus luteum degenerates toward end of secretory phase; progesterone levels fall
  • Causes spiral arteries to kink & spasm
  • Endometrial cells die & glands regress
  • Spiral arteries constrict again, then relax & open wide, causing a rush of blood into weakened capillary beds
  • BVs fragment & functional layer sloughs off & uterine cycle starts all over again - 1st day of menstruation
96
Q

At what age does the descend of gonads start?

A

2 months before birth

97
Q

What stimulates migration of testes toward scrotum?

A

testosterone

98
Q

Do the ovaries descend?

A

YES

99
Q

Describe boundaries where ovaries stop their descent.

A

ovaries stop descending by broad ligament at pelvic brim

100
Q

What is cryptorchidism?

A

failure of testes to make their normal descent

101
Q

Cryptorchidism can increase risk of…

A

sterility & increased risk of testicular cancer

102
Q

What is the usual treatment for unresolved cryptorchidism?

A

surgery

103
Q

How long does sperm last?

A

5 days

104
Q

How long is the window for a woman to become pregnant after intercourse?

A

5-day window

105
Q

How long should you wait for cryptorchidism?

A

If it hasn’t descended in about 1 year they have to go find it.

106
Q

What is the gubernaculum?

A

fibrous cord that guides the testicles into it’s right position

107
Q

When does menopause occur?

A

when menses have ceased for an entire year

108
Q

Describe perimenopause

A

starts in late 30s/early 40s
- periods can become more irregular

109
Q

Is there a menopause equivalent in men?

A

NO

110
Q

Describe sperm production in males as they age.

A

Males cont to produce sperm into 80s, #s & motility decreases

111
Q

Declining estrogen levels cause:

A
  • Irregular menses / menorrhagia
  • Atrophy of reprod. organs/breasts
  • Irritability & depression in some
  • Hot flashes as skin BVs undergo intense vasodilation
  • Gradual thinning of skin & bone loss
  • Incr total blood cholesterol levels & falling HDL
112
Q

Treatment for menopause

A

estrogen-progesterone preps

113
Q

NOTE

A

Less estrogen feeds back on the hypothalamus–> produces FSH goes up
- a rise in FSH to a certain levels is a dx marker for menopause)

114
Q

Describe premature menopause & when it occurs.

A
  • ovaries stop responding to estrogen
  • as early as 25yo

Block 4 - OBGYN (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions