Reproductive System Flashcards
(108 cards)
1
Q
run down of reproductive structures
A
-gonads produce gametes
-ducts recieve and transport gametes
-accessory glands secrete fluids into ducts
-perineal structures collectively known as external genetalia
2
Q
how many sperm do males produce a day
A
-half a billion
3
Q
male reproductive system
A
-testes that secrete male sex hormones and produce male gametes
4
Q
femal reproductive system
A
-ovaries that release on immature gamete per month and produce hormones
-uterine tuves carry oocytes to uterus
-uterus encloses and supports developing embryo
-vagina connects uterus with exterior
5
Q
pathway of sperm
A
-testis
-epididymus
-ductus deferens
-ejaculatory duct
-urethra
6
Q
accessory glands that secrete fluids into the duct
A
-seminal glands
-prostate
-bulbo-urethral glands
7
Q
scrotum
A
-fleshy pich that encloses testes
-suspended inferior to perineum
-anterior to anus
-posterior to base of penis
8
Q
photo of male repro
A
9
Q
accessory glands photo
A
10
Q
what moves sperm from testes
A
-cilia lining the efferent ductules into the spidydmus
11
Q
temperature regulation in testes
A
normal sperm development requires temperatures 1.1degrees below body temp
-muscles relax and contract to move testes to maintain temp
12
Q
mitosis
A
-somatic cell divison
-produces two diploid daughter cells
-both daughter cells have identical numbers and pairs of chromosomes
-members of each pair are homologous chromosomes
13
Q
meiosis
A
-special form of cell division involved only in production of gametes
-produces haploid gametes each with 23 chromosomes
-fusion of male and female gametes produce a zygote with 46 chromosome
14
Q
each chromsome in meiosis has
A
-two chromatids
15
Q
synapsis
A
-maternal and patermal chromosomes come together
-four mathces chromatids form tetrad
-crossing over - exchange of genetic material that increase genetic variation among offspring
16
Q
meiosis I - prophase and metaphase I
A
-prophase I - nuclear envelope disappears
-metaphase I - tetrads line up along metaphase plate
17
Q
anaphase I
A
-tetrads break up,
-two copies of either maternal or paternal chrom to each daughter cell
-maternal and paternal components are randomly and independently distributed
18
Q
telophase I
A
-ends with formation of two daighter cells with unique combination of chromosomes
19
Q
reductional division
A
-reduces number of chromosomes from dipoid to haploid
-both cells contain 23 chromosomes with two chromatids each
20
Q
interphase
A
seperates meioisis I and meiosis II
-very brief
-DNA is not replicated
21
Q
Meiosis II
A
-prophase II
-metaphase II
-Anaphase Ii - chromatids seperate
-telophase II - yields four haploid cells each containing 23 chromosomes
-equational division - number of chromosomes is unchanged
22
Q
sperm production important times
A
-begins at puberty
-continues past age 70
-complete process takes about 64 days
-three steps - mitosis, meiosis and spermatogenesis
23
Q
spermatogonia
A
-divides by mitosis to produce two daighter cells
-one ramins a spermatognium
-second differentiates into primary spermatocyte
24
Q
primary spermatocyte
A
-begin meiosis and form secondary spermatocyte
25
spermatids
-secondary spermatocytes differentiate into spermatids
26
spermatids
-immature gametes
-differentiate into sperm
27
sperm
-lose contact with wall of seminiferous tubule
-enter fluid in lumen
28
mitosis of spermatogonium
29
meiosis I of spermatogenesis
30
meiosis II of spermatogenesis
s
31
second part of meiosis II of spermatogenesis
32
nurse cell photo
33
stages of spermatogenesis within the wall of a seminiferous tubule
34
the differentiation of spermatid into sperm
35
spermiogenesis
-last step of spermatogenesis
-each spermatid matures into one sperm
-major strucutral changes
-at spermiation a sperm loses attachment to nurse cell and enters lumen of ST
36
support of spermiogenesis
-nurse cells surround spermatids, provide nutrients and chemical stimuli for development, and phagocytoze cytosplasm shed by developing spermatids
37
sperm leaving epididymus
-mature but immobile
-to become motile and fully function sperm has to undergo capactiation
38
-capacitation steps
-1 sperm become motile when mixed with secretions of seminal glands
-2- sperm become capacle of fertilization when exposed to female
39
mature sperm lack
-ER
-GA
-lysosomes and peroxisomes
-inclusions
-loss of organelles refuces size and mass
-sperm must absorb nutrients from surrounding fluid
40
nurse cells
-sertoli cells
-maintain blood, testis barrier
-support of mitosis and meiosis
-support of spermatogenesis
-secretion of inhbin
-secretion of androgen binding protein
41
inhibin
-depresses pituitary production of FSH, and perhaps hypothalamic secretion of GnRH
-regulation of FSH and GnRH by inhibin allows negative feedback control of spermatogenesis
-as rates of sperm production increase, secretion of inhibin increases
42
Androgen binding protein
-binds androgens (primarily testosterone)
-in luminal fluid of ST
-important for elevating androgen concentration and stimulating spermatogenesis
-production of ABP is stimulated by FSH
43
nurse cells are stimulated by
FSH and testosteron
44
stimulation of nurse cells promote
-division of spermatogonia
-meiotic division of spermatocyte
45
blood testis barrier
-isolated ST from general circulation
-nurse cells maintain this barrier
-nurse cells joined by tight junctions dividing ST into compartmments
-outer basal compartments contain spermatogonia
-inner luminal compartments is where meiosis and spermiogenesisi occur
46
FSH and testosterone influence/control
-target nurse cells of ST
-nurse cells secrete inhibin and ABP, and promote spermatogenesis and spermiogenesis
47
GnRH hormal influence and control
-gonadotroping releasing hormone
-synthesized in hypothalamus
-carrier to pituiatry by hypohyseal portal system
-secreted in pulses (60-90min intervals)
-controls rate of secretion of FSH and LH and testosterone
48
inhibin influence and control
-inhibits FSH production in pit. gland
-perhaps supresses secretion of GnRH at hypothalmus
-faster rates of sperm production cause more inhibin to be secretes
49
LH influence and control
-targets instersitial endocrine cells of testes
-induces secretion of testosteron and other androgens
50
testosterone influence and control
-sexual function
-steroid homrones
-circulates in bloodstream bound to one of two transport protein
-diffuse across target cell membrane and binds to intracellular receptor
51
effects of testosterone
-stimulates spermatogenesis
-libido
-stimulates bone and muscle growth
-establishes and maintaines male secondary sex characteristics
-maintains accessory glands and organs of male reproductive system
52
DHT
-dihydroxytestosteron
-some testosterone converted to DHT in target tissues
-some DHT diffuses into bloodstream
-can binds to same receptors as testosterone
-some tissues respond to DHT instead of testosterone
53
estradiol
-small amount in plasma of males
-formed by testosterone by aromatase
-production increases in older men
54
oogenesis timeline
-begins before birth
-accelerates at puberty
-ends at menopause
55
fetal ovaries
-contain oogonia that undergo mitosis and produce diploid primary oocytes
56
oogenesis at birth
-ovaries contain 2 mil primary oocytes
most oocytes degenerate in atresia
-oocytes that survive remain at prophase I until puberty
57
oogenesis at puberty
-400 000 primary oocytes remain
-some are stimulated to finishe meioisis I producing haploid secondary oocytes
58
mitosis of oogonium
59
meiosis I of oogenesis
60
oogenesis
-cytoplasm of primary oocytes ivides unevenly producing one secondary oocyte with most of original cytoplasm
-two or 3 polar bodies that disintegrate
-ovary release secondary oocyte thats suspended in metphase II
-Meiosis II is completed upon fertilization after which a mature ivum is formed
61
process of oogenesis
-primary oocytes remain suspended in development until puberty
-at puberty FSH rises starting ovarian cycle
-each month after, some primary oocytes are stimulated to develop further
62
Meiosis II of oogenesis
63
ovarian follicles
-specialized structures in cortex of ovaries
-oocyte growth and meiosis I occur
64
primary oocytes
-located in outer part of ovarian cortex near tunica albuginea in clusters called egg nests
65
primordial ovarian follicle
-primary oocyte and its surrounding follce
-zona pellucida - area of intermingling microvilli of follcile cells and surface of oocyte
66
primordial ovarian follicles in egg nest
67
secondary ovarian follicle
-forms from primary ovarian follicle
68
tertiary ovarian follicle
follicular fluid accumulated between inner and outer cellular layers
-twice the size of secondary ovarian follicle
69
follicular phase (preovulartory phase)
-tertiary ovarian follcile creates bulge in ovary
-oocyte and its follicular cells project into antrum
-rising LH levels prompt completion of meiosis I
-corona radiata are granulosa cells that remain associated with secondary oocyte
70
luteal phase - post ovulatory phase
-corpus luteum
71
corpus luteum
-forms fromremaining granulosa cells under stimulation of LH
-yellow due to cholesterol
-cholesterol converted to progesterone to prep uterus for pregancy
-secretes modetae amount of estrogens
-begins degenrating 12 days after ovulation
72
ovulation
-tertiary fllicle releases secondary oocyte into pelvic cavity
-oocyte moves into uterine tube by contact with fimbriae or by fluid currents
-ovarian follicles that started but did not complete development undergo atresia
73
photo of follicle development
74
uterine cycle (menstrual cycle)
-repeating series of changes in endometrium
-lasts from 21-35 days, averaging 28 days
-
75
menarche
-first uterine cycle
-begins at puberty (age 11-12)
76
menopause
-termination of uterine cycle
-age 45-55
77
three phases of uterine cycle
-menstrual phase
-proliferative phase
-secretory phase
78
menstrual an proliferative phases occur when
-occur during ovarian follicular phase
79
secretory phase occurs when
-during ovarian luteal phase
80
menstrual phase
-degeneration of endometrial functional layer occuring in patches and leads to menstruation
-caused by constriction of spiral arteries reducing blood flow, oxygen and nutrients
-weakened arterial walls rupture releasing blood into connective tissues of functional layer
81
proliferative phase
-epithelial cells of uterine glands multiply and spread across endometrial surface and restore integrity of epithelium
-further growth and vascularization completely restore functional layer
-occurs at the same time as enlargement of tertiary follicles
-stimulated and sustained by estrogens secreted by developing ovarian follicles
-entire functional layer is highly vascularized
-small arteies spiral toward inner surface from larger arteries in mymometrium
82
secretory phase
-uterine glands enlarge increasing rate of secretion
-arteries of uterine wall elongate and spiral through functional layer
-begins at ovulation and persists as long as CL remains instact
-secretion peaks about 12 days after ovulation
-generally lasts 14 days
-ends as CL stops producing hormones
83
menses
-entire functional layer is lost rhough esternal os ad vagina
-only functional layer is affected (deeper layer supplied by straight arteries)
-35-50mL blood lost
84
dysmenorrhea
-painful menstruation
-several causes
85
hormones influence on the reproductive cycle
-GnRH from hypothalamus changes in pulse freuqnecy and amplitude over course of ovarian cycle
-estrogens increase pulse frequency
-progesterone decrease pulse frequency
-groups of endocrine cells in anterior pituiatary respond to different GnRH pulse frequencies, sensitive to some insensitive to others
86
increased pulse frequency of GnRH
-stimulates LH secretion
87
hormone on day 10 of ovarian cycle
-effect of estrogen on LH secretion changes from inhibition to stimulation
-switchover occurs when levels of estrogens exceed threshold value for about 35 hours
88
day 14 of ovarian cycle hormones
-massive release of LH from anterior lobe of pituitary gland
89
sudden surge in LH concentration triggers
1. completion of meioisis by pirmary oocyte
2. rupture of follicular wall
3. ovulation
90
hormonal regulation of follicular phase
-FSH stimulates follicular development
-Monthly, some teritary ovarian follicles begin to grow
-As follicles enlarge, thecal endocrine cells produce androstendione
91
androstenedione
-intermediate steroid hormone
-absorbed by granulosa cells and converted to estrogens
92
thecal endocrine cells
-in ovarian stroma
-secrete small amounts of estrogens
93
circulating estrogens
-bound primarily to albumins
-lesser amounts carried by gonadal steroid binding globulin
-three types: estradiol ,estrone and estriol
94
estradiol
-most abundant
-most pronounced effect of target tissues
-dominant hormone prior to ovulation
95
estrogen synthesis
-androstenedione is converted to testosterone
-aromatase converts testosterone to estradiol
-estrone and estriol are synthesized directly from androstenedione
96
conversion of progesterone and androstendione to other estrogens
97
six functions of estrogens
-stimulate bone and muscle growth
-maintain female secondary sex characteristics
-affect CNS activity, especially in hypothalamus where estrogens increase sex drive
-maintian functional accessroy repro glands and organs
-initiate repair and growth of endometrium
-maintain thin/uncalcified vascular plaque thereby reducing CV risk
98
hormonal regulation of luteal phase
-high LH levels that promote progesterone secretion and trigger formation of CL
-low frequency of GnRH pulses stimulates LH secretion more than FSH secretion
-LH maintains structure and secretory function of CL
99
luteal phase progesterone levels
-progesterone levels remain high for 1 week
-CL degenrates unless pregnant
-progesterone and estrogen levels drop
-GnRH pulse freuquency increase stimulating FSH secretion and ovarian cycle begins again
100
ovarian cycle hormone levels graph
101
hormonal regulation of uterine cycle
-proliferative phase continues until rising progesterone starts secretory phase
-increase in estrogen and progesterone causes enlargement of uterine glands and increase in secretory activities
102
hormones and body temp
-monthly hormone fluctuations affect core body temp
-follicular phase, estrogens dominate and basal body temp drops 0.3 degrees
-during luteal phase, progesterone dominates
-upon ovulation basal body temp decreases briefly
-a day after ovulation, temperature rises and remains high throughout luteal phase
103
endometrial changes graph
104
aging effects on male and female repro system
-female - menopause
-male - comparable age related changed occur gradually over longer time period
105
perimenopause
-interval immediately preceding menopause
-ovarian and uterine cycles become irregular due to shortage of primordial ovarian follicles
-levels of estrogens decrease and ovulation may not be triggered
106
menopause
-time that ovulation and menstruation cease
-typically occurs at age 45-55
-age 50 = typically no primarodial follicles left
-premature menopause, depletion of primrodial follicles before age 40
-circulating concentrations of estrogens and progesterone decline
-rise in GnRH, FSH, LH sharply
107
male climactric (andropause)
-period of declining repro function
-between ages 50 and 60
-circulating testosterone begins to decrease
-circulating FSH and LH increase
-sperm production continues
-sex activity decreases with decreasing testosterone levels
108
menstrual cycle graph again
